The disclosure relates to apparatus and systems for belt-roll fuser stripping. In particular, the disclosure relates to self-positioning stripping apparatus and systems for use in belt roll fuser systems.
Related art belt-roll fusers include a hard internal pressure roll and a soft external pressure roll. The internal pressure roll, or fuser roll, and the external pressure roll, or pressure roll, may together form a fusing nip for fusing marking material such as toner to a sheet, after the sheet has received toner from a transfer station. A fuser belt may be entrained by the internal roll and three heated rolls that also contact the fuser belt, the fuser belt extending through the nip.
During a printing process, a paper sheet that is fused at the nip may stick to the fusing belt after passing through the nip. Typically, a strip shoe is implemented to strip the sheet from the fusing belt. The strip shoe may have, for example, a less than 5 mm stripping radius. The fusing belt wraps around the strip shoe causing a bend in the belt at which paper leaves the belt surface during processing. Related art fusing nips cause image quality defects such as “retacking”, gloss defects such as “icicles”.
Related art strip shoe configurations are difficult to control. Self-position stripping apparatus and systems may eliminate the strip shoe to soft external roll configuration by including an internal pressure roll having a soft surface, and an external pressure roll having a hard surface, for example. A strip bar, for example, may be mounted to a pivoting plate system for automatically positioning the strip bar in an operating position that is close to the hard external pressure roll.
In an embodiment, belt-roll fuser stripping apparatus may include a mounting plate for mounting a stripping shoe, the mounting plate being configured to movably connect to an internal pressure roll; and a stripping shoe for stripping a sheet from a fuser belt, the stripping shoe being attached to the mounting plate. In an embodiment, apparatus may include an internal pressure roll; an internal pressure roll bearing, the internal pressure roll bearing being attached to the internal pressure roll, and the mounting plate being attached to the internal pressure roll bearing whereby the mounting plate is movably connected to the internal pressure roll.
In an embodiment, apparatus may include a fuser belt, the fuser belt being entrained by at least the internal pressure roll, the fuser belt having an internal pressure roll contact side and a sheet contact side, the fuser belt wrapping around the stripping shoe whereby the stripping shoe contacts the roll contact side of the fuser belt to angle the fuser belt.
In an embodiment, apparatus may include an internal pressure roll having a conformable surface. In an embodiment, the internal pressure roll may include a soft surface comprising rubber. The internal pressure roll bearing may be configured to permit rotation of a mounting plate about a rotational axis of the internal pressure roll. In an embodiment, a force applied to the fuser belt by the stripping shoe may adjusted by moving the mounting plate about the internal pressure roll bearing. In an embodiment, a mounting plate ski, the mounting plate ski being configured to limit rotation of the mounting plate about a rotational axis of the internal pressure roll.
In an embodiment, a mounting plate ski may be attached to the mounting plate. In an embodiment, a mounting plate ski may be configured for restricting movement of a mounting plate whereby a stripping shoe may be automatically positioned to apply a desired pressure to a roll contact side of a fuser belt.
In an embodiment of systems, self-position stripping systems may include a mounting plate, the mounting plate configured for supporting a strip shoe; an internal pressure roll; an internal pressure roll bearing, the internal pressure roll bearing being connected to the internal pressure roll, the mounting plate being attached to the internal pressure roll bearing whereby the mounting plate is movable about a rotational axis of the internal pressure roll. In an embodiment, systems may include an external pressure roll. Systems may include the internal pressure roll having soft surface, and the external pressure roll having a hard surface. Systems may include the mounting plate being spring biased, the mounting plate being biased toward an external pressure roll when the internal pressure roll is engaged with the internal pressure roll to define a fusing nip. In an embodiment, systems may include a mounting plate ski, the mounting plate being spring biased toward a first direction; an external pressure roll bearing, the external pressure bearing being movably attached to the external pressure roll, the mounting plate ski being configured to contact the external pressure roll bearing.
In an embodiment, systems may include the mounting plate being biased by a spring that applies a biasing force in a first direction that causes the mounting plate to move toward the external pressure roll, the ski being configured to contact the external pressure roll bearing whereby the external pressure roll bearing applies a force in a second direction that opposes the first direction of the biasing force. Systems may include the mounting plate being movable to and from a first position wherein the ski contacts the external pressure roll bearing, and a second position wherein the ski does not contact the external pressure roll bearing.
In an embodiment, systems may include the mounting plate being a first mounting plate, the system including a second mounting plate, the strip shoe being attached to the second mounting plate, second mounting plate. In an embodiment, systems may include the internal pressure roll bearing being a first internal pressure roll bearing, and a second internal pressure roll bearing, the second mounting plate being attached to the second pressure roll bearing. In an embodiment, when the ski contacts the external pressure roll bearing, the strip shoe applies a force against fuser belt toward the external pressure roll for form a bend in the fuser belt at a portion of the strip shoe that contacts the fuser belt.
Exemplary embodiments are described herein. It is envisioned, however, that any system that incorporates features of apparatus and systems described herein are encompassed by the scope and spirit of the exemplary embodiments.
Exemplary embodiments are intended to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the apparatus and systems as described herein.
Reference is made to the drawings to accommodate understanding of self-positioning stripping apparatus and systems for belt roll fuser systems. Belt roll fuser systems may be used in printing systems for fusing an image to a sheet at a fusing nip. In the drawings, like reference numerals are used throughout to designate similar or identical elements. The drawings depict various embodiments of illustrative self-stripping apparatus and systems.
Apparatus and systems of embodiments may include systems for printing images on substrates such as paper sheets. The printing process includes a fusing step wherein marking material such as toner is fused to the sheet using heat and pressure. Exemplary substrates may include media webs, such as a paper webs. Alternatively, the system may be configured to feed cut sheets to a fixing or fusing nip of the belt-roll fuser.
A related art belt-roll fuser system is shown in
The external pressure member 110 may be removable. Accordingly, when the belt-fuser apparatus 101 is separated from the belt-roll fuser main frame 102, the external pressure member 110 may be accessed for cleaning and/or servicing. For example, the external pressure member 110 may be customer replaceable.
The external pressure member 110 may be associated with a pressure roll cooling system. For example,
As shown in
The belt-roll fuser apparatus 101 may include a plurality of belt members. The belt members may be rolls, as shown, that rotatable about an axis, e.g., a longitudinal access, to facilitate movement of a fuser belt. The belt members may be rolls that support, clean, and/or steer the belt as it translates about the plurality of members and an internal pressure member. For example,
The belt-roll module 101 may include a cleaner member 127 positioned so that the internal pressure member 120 interposes the cleaner member 127 and the external pressure member 110 when the belt-roll module 101 is positioned to engage the internal pressure member 120 with the external pressure member 110 of the main frame of the belt-fuser system 100. The cleaner member 127 may be a rotatable member that facilitates support and translation of a belt. For example, the cleaner member 127 may be a roll, such as a cylindrical roll that is rotatable about its central longitudinal axis. The cleaner roll 127 may be associated with, for example, a web cleaning system or a belt cleaning system. A web cleaning system may include a plurality of members that facilitate cleaning of a web or belt of the belt-roll fuser system. The web cleaning system may be customer replaceable, facilitated by, e.g., the latching and unlatching operability of the belt-roll fuser module 101. The internal pressure member 120 may be associated with a metering system. A metering system may include one or more metering members, such as a media roll.
The belt-roll fuser apparatus 101 of
Each of the internal pressure member 120, the cleaner member 127, the belt member 130, and the tension member 133 may be configured to entrain a belt 143. The belt 143 may translate about the rotatable members, and may absorb heat from heated entraining rotatable members or rolls. The belt 143 may be replaceable. For example, the belt-fuser apparatus 101 may be positioned to accommodate access to components of the belt-roll fuser module 102 thereby enabling, e.g., user replacement of the belt 143. Belt thermistors (not shown) may be arranged about the belt 143.
The belt 143 may pass through a nip defined by the internal pressure member 120 of the belt-roll apparatus 101 and the external pressure member 110 when, e.g., the belt-roll apparatus 101 is latched to the main frame 102. Post-fusing processing components may be situated about the nip; specifically, about an exit of the nip. For example, an air knife 145 may be at the exit nip. Also, a stripping shoe 147 may be configured to interpose the internal pressure roll 120 and the belt 143 for bending the belt at a stripping angle to form a corner of the belt 143 at the nip exit at which the sheet may be stripped from the belt. The belt 143 may be wrapped around a corner of the stripping shoe 147, at which point paper may caused to leave a surface of the belt that extends in a process direction beyond the corner of the stripping shoe 147.
An exit sensor 150 may positioned at an exit of the fusing nip. A substrate having a fused image may be carried by a post-fuser transport system 155 after the substrate exits the fusing nip.
The zones of the related art nip profile include: N1, a high pressure nip zone (e.g., about 60 psi to about 80 psi); N2, a low pressure nip zone (e.g., about 6 psi to about 10 psi) where the fuser belt 243 changes direction, e.g., is guided in a direction away from the fuser roll 220; and N3, a nip zone (e.g., 0 psi) where there is substantially of the fuser belt 243 by the external pressure roll 210, and where the belt 243 from the external pressure roll 210 and is tangent with the stripping shoe 247 tip radius.
Image quality defects are typical at nip zones N2 and N3. For example, changes in a bend direction of a sheet as the sheet travels through the nip at zone N2, as shown in
A sheet may stick to the belt 243 and/or to the external pressure roll 210 as the sheet travels through the N3 nip zone, depending on imaging density and image location. A sheet may separate and then re-touch the belt 243 causing image defects such as ‘retack”.
To ensure effective stripping, it is desirable to increase the stripping angle, increasing the angle at which the belt wraps around the stripping shoe. The stripping shoe must be positioned so that the shoe does not contact and damage the external pressure roll. Accordingly, variations in external pressure roll centerlines must be accounted for, limiting the effective stripping angle. Accordingly, a sheet leaves the hard nip at N2 before being stripped from belt fuser components until after a lead edge of the sheet reaches the strip shoe 247, past zone N3.
The belt roll fuser apparatus may include an internal pressure roll 320. The internal pressure roll or fuser roll 320 may entrain a fuser belt 343. The internal pressure roll 320 may comprise a soft surface, and may be formed of, for example, rubber. The belt 343 may be formed of polyimide viton. The belt 343 and pressure rolls 322 may be configured to form a composite fusing nip when operably engaged with the external pressure roll 310, wherein internal the pressure roll 320 contacts external pressure roll 310 to form the fusing nip
A strip shoe 346 may be configured to apply a force against the belt 343 toward the external pressure roll 310. The strip shoe 346 may form a metal bar for example. The angle at which the belt wraps around the strip shoe is larger than the stripping angle shown in
The stripping shoe may be mounted on a pivoting plate system. The pivoting plate system may be mounted on bearings attached to the internal pressure roll 320. A spring force may be implemented for biasing the pivoting system inward and toward the nip, in a clockwise direction with respect to
When the internal pressure roll 420 is engaged with the external pressure roll 410 to form a fusing nip, the mounting plate 460, internal pressure roll bearing 462, and external pressure roll bearing 411 may be configured so that a ski 465 attached to the mounting plate contacts the external pressure roll bearing 411. For example, the ski 465 may be constructed and arranged to slidably contact the external pressure roll bearing 411, enabling the mounting plate to track the position of the external pressure roll 410, and preventing the stripping shoe attached to the plate 460 from extending beyond a desired distance between the shoe and a surface of the external pressure roll 410.
A mounting plate 460 may be included on either or both sides of the internal pressure roll 420. Similarly, the internal pressure bearing 462, external pressure roll bearing 411, and ski 465 may be configured on either or both sides of the internal and external pressure rolls.
A biasing system 467 may include, for example, a spring attached to a frame of the belt roll fuser apparatus. The spring 467 may be configured to bias the mounting plate 460, which may be rotatably attached to the internal pressure roll bearing 462, toward the nip so that the ski 465 is forced against the external pressure roll 411. Accordingly, the shoe may be forced against the belt 443, the shoe being positioned a desired distance from the external pressure roll 410.
As the external pressure roll 410 is raised to engage the internal pressure roll 420 for forming a fusing nip for a printing operation, an outside diameter of the external pressure roll bearing 411 may be configured to engage the ski(s) 465, causing the plate to rotate counter clockwise in a direction “A” by applying a force in a direction “B” until the external pressure roll 410 has finished moving in a direction “C” to form the nip. The configuration accommodates self-location or automatic position of the tip of the strip shoe relative to the external pressure roll 410. Because the plate system tracks the location of the external pressure roll by way of the external pressure roll bearing 411, variation in a location of internal pressure roll 420 and external pressure 410 rotational axis centerlines would have little effect on a location of the strip shoe relative to the surface of the external pressure roll 410.
When the internal pressure roll 520 is engaged with the external pressure roll 510 to form a fusing nip, the mounting plate 560, internal pressure roll bearing 562, and external pressure roll bearing 511 may be configured so that a ski 565 attached to the mounting plate contacts the external pressure roll bearing 511. For example, the ski 565 may be constructed and arranged to contact the external pressure roll bearing 511, enabling the mounting plate to track the position of the external pressure roll 510, and preventing the stripping shoe attached to the plate 560 from extending beyond a desired distance between the shoe and a surface of the external pressure roll 510, the mounting plate 560 being biased toward the external pressure roll 510. A mounting plate 560 may be included on either or both sides of the internal pressure roll 520. Similarly, the internal pressure bearing 562, external pressure roll bearing 511, and ski 565 may be configured on either or both sides of the internal and external pressure rolls.
A strip shoe 547 may be attached to the mounting plate 560. In an embodiment having two mounting plates, the strip shoe 547 may be attached to both mounting plates, one mounting plate being attached to each side of the strip shoe assembly. The strip shoe 547 mounted to the one or more mounting plates 560 may be configured to apply a force to the fuser belt 547 so that the belt 547 wraps around a tip or corner of the strip shoe 547, corresponding to a point at which a sheet that exist the fusing nip separates from the fuser belt 543. The strip shoe 547 mounted to the one or more mounting plates 560 may be configured for applying a force to the belt 543 that minimizes a low pressure zone at the nip exit where no pressure or mere belt tension is applied to the sheet.
The mounting plate 560 may be configured to be rotatable about the internal pressure roll bearings 562 in both a clockwise and a counter-clockwise direction. The mounting plate 560 may be rotated counter-clockwise in a belt fuser system for moving the stripping finger away from the external pressure roll, thereby applying a lesser force than the strip shoe 547 would apply to the belt 543 in the configuration shown in
A biasing system 567 may include, for example, a spring attached to a frame of the belt roll fuser apparatus. The spring 567 may be configured to bias the mounting plate 560, which may be attached to the internal pressure roll bearing 562, toward the nip so that the ski 565 is forced against the external pressure roll 511. Accordingly, the shoe may be forced against the belt 543, the shoe 547 being positioned a desired distance from the external pressure roll 510.
As the external pressure roll 510 is raised to engage the internal pressure roll 520 for forming a fusing nip for a printing operation, an outside diameter of the external pressure roll bearing 511 may be configured to engage the ski(s) 565, causing the plate to rotate counter clockwise in a direction “A” by applying a force in a direction “B” until the external pressure roll 510 has finished moving in a direction “C” to form the nip. The configuration accommodates self-location or automatic position of the tip of the strip shoe 547 relative to the external pressure roll 510. Because the plate system tracks the location of the external pressure roll by way of the external pressure roll bearing 511, variation in a location of internal pressure roll 520 and external pressure 510 rotational axis centerlines would have little effect on a location of the strip shoe 547 relative to the surface of the external pressure roll 510.
While apparatus and systems for self-positioning stripping system are described in relationship to exemplary embodiments, many alternatives, modifications, and variations would be apparent to those skilled in the art. Accordingly, embodiments of apparatus and systems as set forth herein are intended to be illustrative, not limiting. There are changes that may be made without departing from the spirit and scope of the exemplary embodiments.
It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also, various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art.