Abstract:
The adjustment method aligns printing engines in a print assembly that is capable of printing on a receiver to form one or more final prints and includes corrections for cross-track misregistration. These adjustments are made in one embodiment by aligning two or more printing engines in an x and y direction relative to a paper path cross track reference and then aligning each printing engines in a cross track direction (z direction) relative to the paper path cross track reference based on measurements in the cross track direction (z direction) relative to the paper path cross track reference.
Abstract:
A print engine synchronization method enables the movement of a first print engine dielectric support member (DSM) having one or more image frames as well as the movement of a second print engine DSM having one or more image frames by monitoring a first frame signal from the moving first print engine DSM and a second frame signal from the moving second print engine DSM. An offset is determined for each of corresponding pairs of frames from the one or more image frames of the first and second print engine DSM and the determined offset for each corresponding pair of frames is compared to a target offset to maintain synchronization between the first and second print engines on a frame by frame basis by adjusting a second print engine DSM velocity based on the comparison of the determined offset and the target offset.
Abstract:
A sheet feeder comprising a platform for stacking sheets and feed head assembly at the front of the platform for acquiring individual sheets from the stack and feeding separate sheets into a sheet handling machine. The feed head assembly is comprised of a vacuum plenum having a port plate, across which a perforated belt(s) moves in a closed loop. The port plate includes ports wherein the air flow through some of the ports is restricted by an intermediate plate positioned within the plenum which, in turn, has a restrictive passage therein through which air from the restricted ports must flow into the plenum.
Abstract:
A device for transporting material, in the form of discrete sheets, seriatim to a stack of discrete sheets, and subsequently seriatim away from such stack. The discrete sheet material transport device comprises a support for a stack of discrete sheets. The stack support includes a first stop for a first marginal edge of a discrete sheet, and opposed second and third stops for opposed marginal edges of a discrete sheet perpendicular to the first marginal edge of such discrete sheet. Discrete sheets are delivered seriatim to the vicinity of the stack support and are urged in a first direction into engagement with the first stop to form a stack of discrete sheets on the stack support. The discrete sheets are subsequently urged seriatim in a direction opposite the first direction to remove discrete sheets seriatim from the stack on the stack support. The second and third stops are located to accurately position the stack of discrete sheets on the stack support. Further, the second and third stops are substantially simultaneously oscillated to maintain such stack in the accurate position as such discrete sheets are urged to and from the stack on the stack support.
Abstract:
Apparatus for feeding sheets seriatim from a sheet supply stack. The apparatus comprises a sheet feed head assembly including a plenum, a vacuum source in flow communication with the plenum, and a mechanism, such as a feed belt, for example, associated with the plenum for urging a sheet acquired by vacuum in a sheet feeding direction away from the sheet supply stack. The sheet supply stack is supported, for example in a hopper on a support platform, so as to maintain the topmost sheet in such stack at a predetermined level in spaced relation with respect to the urging mechanism of the sheet feed head assembly. A first positive air supply directs a flow of air at the sheet supply stack to levitate the top several sheets in the supply stack to an elevation enabling the topmost sheet to be acquired by vacuum from the sheet feed head assembly plenum; and a second positive air supply directs a flow of air at an acquired sheet to assure separation of any additional sheets adhering to such topmost sheet.
Abstract:
A method of increasing productivity in a reproduction apparatus wherein a first print engine and a second print engine are coupled by an inverter and synchronized. Each sheet of a plurality of receiver sheets is selectively printed in an invert mode or a non-invert mode. A difference of a travel time of a first receiver sheet in an invert path through the inverter in the invert mode as compared to a travel time of a second receiver sheet in a non-invert path through the inverter in the non-invert mode is adjusted so that the difference is an integral multiple of a period between the receiver sheets. Frames on a dielectric support member in the appropriate print engine are skipped when switching between invert mode and non-invert mode.
Abstract:
A method for reducing artifacts on a toned sheet caused by buckling during fusing includes providing two compliant rollers that form a fusing nip for fusing the toned sheet. A control drives at least one of the rollers at a nominal speed to cause the rollers to rotate and there after increasing the roller speed to high speed prior to the sheet arriving at the fusing nip and after the sheet is in the nip increasing the drive speed back to the nominal speed.
Abstract:
A magnetic brush development station for a reproduction apparatus has a housing forming, at least in part, a reservoir for developer material; a developer roller mounted within the housing for delivering developer material to a dielectric support member in a development zone; a transport mechanism for transporting developer material from the reservoir to the developer roller; a metering skive for establishing a developer material metering gap; and a mechanism for selectively moving the metering skive to an operative position relative to the developer roller and to a position remote from the developer roller, wherein a build up of contamination at the metering gap between the metering skive and the developer roller can be substantially prevented. A method of removing a skive blockage from a metering skive in a magnetic brush developer station is also disclosed.
Abstract:
A magnetic brush development station for a reproduction apparatus has a housing forming, at least in part, a reservoir for developer material; a developer roller mounted within the housing for delivering developer material to a dielectric support member in a development zone; a transport mechanism for transporting developer material from the reservoir to the developer roller; a metering skive for establishing a developer material metering gap; and a mechanism for selectively moving the metering skive to an operative position relative to the developer roller and to a position remote from the developer roller, wherein a build up of contamination at the metering gap between the metering skive and the developer roller can be substantially prevented. A method of removing a skive blockage from a metering skive in a magnetic brush developer station is also disclosed.
Abstract:
The adjustment method aligns printing engines in a print assembly that is capable of printing on a receiver to form one or more final prints and includes corrections for cross-track misregistration. These adjustments are made in one embodiment by aligning two or more printing engines in an x and y direction relative to a paper path cross track reference and then aligning each printing engines in a cross track direction (z direction) relative to the paper path cross track reference based on measurements in the cross track direction (z direction) relative to the paper path cross track reference.