Vented skive assembly for a fuser station in an image-forming machine

Information

  • Patent Grant
  • 6564030
  • Patent Number
    6,564,030
  • Date Filed
    Wednesday, December 13, 2000
    23 years ago
  • Date Issued
    Tuesday, May 13, 2003
    21 years ago
Abstract
This invention provides a fuser station with a vented skive assembly for an image-forming machine. The image-forming machine may have a photoconductor, a primary charger, an exposure machine, a toning station, a transfer charger, and a vented fuser station. The fuser station may include a pressure roller, a fuser roller, and a skive assembly. The skive assembly has rib sections forming one or more slots, which are configured to provide an airflow pattern to reduce condensation. The skive assembly may have an insert protection device disposed in one or more of the slots.
Description




FIELD OF THE INVENTION




This invention generally relates to fuser stations for image-forming machines. More particularly, this invention relates to fuser stations having a vented skive assembly to reduce the condensation of water vapor in the fuser station.




BACKGROUND OF THE INVENTION




An image-forming machine transfers images onto paper or other medium. The image-forming machine usually includes a photoconductor, one or more chargers, an exposure machine, a toning station, a fuser station, and a cleaner. The image-forming machine also has an environmental system, which may be an air exchanger, fan, or similar device to pull or push air through the image-forming machine.




Generally, the photoconductor is selectively charged and optically exposed to form an electrostatic latent image on the surface. Toner is deposited onto the photoconductor surface. The toner is charged, thus adhering to the photoconductor surface in areas corresponding to the electrostatic latent image. The toner image is transferred onto a sheet of paper or other medium. In the fuser station, the sheet is heated causing the toner to fix or adhere to the paper or other medium. The photoconductor is refreshed, cleaned to remove residual toner and charge, and is then ready to make another image. The sheet exits the image-forming equipment.





FIG. 13

shows a side view of a typical fuser station for an image-forming machine according to the prior art. The fuser station has a fuser roller, a pressure roller, and upper and lower skive assemblies.

FIG. 14

is a perspective view of an upper skive assembly according to the prior art. The fuser and pressure rollers are disposed to form a nip or pinch region. The pressure roller rotates counterclockwise as indicated by the arrow A. The fuser roller rotates clockwise as indicated by arrow B. One or more heater rollers (not shown) heat the fuser roller. The pressure roller also may be heated. The upper and lower skive assemblies are disposed adjacent to the nip region to help remove and guide the sheet away from the pressure and fuser rollers. The upper skive assembly has finger portions that project toward the nip region.




The fuser station causes the toner to fix or adhere to the sheet. In this fixing process, a sheet of paper or other medium passes through the pressure and fuser rollers in the direction indicated by arrow C. As the sheet passes through the rollers, the constriction of the nip region presses the toner onto the surface of the sheet. At the same time, the fuser roller transfers heat to the sheet, causing the toner to fuse to the sheet. The rotation of the rollers pulls the sheet through the nip region.




The constriction and pressure of the rollers and the heating of the toner in the nip region may cause the sheet to stick or attach to the pressure roller. However, the leading edge of the sheet is guided between the upper and lower skive assemblies. If the sheet is stuck to the pressure roller, the finger portions of the upper skive assembly catch the leading edge of the sheet. The finger portions guide the leading edge between the upper and lower skive assemblies, thus pulling the sheet away from the pressure roller as the sheet moves out of the nip region.




The fixing process is usually done at about 355° F. At this temperature, water evaporates or is driven out of the sheet in the form of water vapor. The water vapor condenses in condensation zones on the surface of the upper skive assembly. The condensed water vapor forms droplets that trickle down the upper skive assembly. The droplets may fall onto a sheet as it passes under the upper skive assembly. The water droplets cause the sheet to swell and leave a deformed spot or track on the sheet. The result is a visual defect on the sheet.




The quantity of water vapor is highly dependent upon the moisture content of the paper. If the moisture content is less than about five percent by weight, there may be less condensation on the upper skive assembly. If the moisture content is more than about five percent by weight, there may be more condensation on the upper skive assembly. The amount of condensation also depends on the number of sheets in an image-forming job. Condensation may accumulate in an image-forming job having a large number of sheets even though the moisture content is low. While the first sheets may be clean, the later sheets may have water droplet defects.




There are several approaches to eliminate or minimize condensation on the upper skive assembly. The image-forming machine may be restricted to use only low moisture paper. However, it is impracticable if not impossible for a user of the image-forming machine to determine the moisture content of the paper or other medium immediately prior to use. The storage method and humidity often affect the moisture content, causing it to vary from time to time. Additionally, the moisture content of the paper or other medium may be reduced or lowered. However, the equipment and time required makes this approach impracticable. It also is impracticable for a user to limit the size of image-forming jobs.




The upper skive assembly or a nearby part may be maintained at a temperature high enough to eliminate the cold surfaces where condensation may occur. However, additional equipment is required such as heating elements or the like for upper skive assembly or the other part. The higher temperature also may expand or distort the upper skive assembly, causing the finger portions to project too far or unevenly into the nip region. Additionally, the energy required to heat the upper skive assembly or other part increases operating costs for the image-forming machine.




The fuser station also may have additional venting or increased airflow to remove water vapor before condensation occurs. The additional venting and increased airflow may require additional equipment such as a larger environmental system or fan. In addition, the configuration of the upper skive assembly may create “dead” zones where the air does not flow well. The water vapor may accumulate and condense in these dead zones rather than flow out of the fuser station.




Accordingly, there is a need for a fuser station in an image-forming machine that reduces the condensation of water vapor.




SUMMARY




This invention provides a fuser station with a vented skive assembly for an image-forming machine. The skive assembly has one or more slots that provide an airflow pattern to reduce condensation in the fuser station. The heat used during the fixing process in the image-forming machine may evaporate water from a sheet. The environmental system or other convective airflows in the image forming machine pass the water vapor through the one or more slots.




The image-forming machine may have a photoconductor, a primary charger, an exposure machine, a toning station, a transfer charger, and a vented fuser station. The primary charger electrostatically charges the photoconductor. The exposure machine optically exposes and forms an electrostatic image on the photoconductor. The toning station applies toner onto the photoconductor. The toner has a charge to adhere to the electrostatic image. The transfer charger transfers the toner from the photoconductor onto a sheet. The fuser station receives the sheet from the transfer charger and fuses the toner onto the sheet.




The fuser station may include a pressure roller, a fuser roller, and a skive assembly. The fuser roller forms a nip region with the pressure roller. The skive assembly catches the sheet as it advances out of the nip region in a sheet direction. The skive assembly has rib sections, which may project from the skive assembly toward the nip region. One or more finger portions may provide the rib sections. The skive assembly also may have a support member connected to the rib sections and the finger portions. The rib sections form one or more slots, which are configured to provide an airflow pattern that reduces condensation on the skive assembly. The skive assembly may have an insert protection device disposed in one or more of the slots. The insert protection device prevents or corrects a sheet stubbing the slot.




Other systems, methods, features, and advantages of the invention will be or will become apparent to one skilled in the art upon examination of the following figures and detailed description. All such additional systems, methods, features, and advantages are intended to be included within this description, within the scope of the invention, and protected by the accompanying claims.











BRIEF DESCRIPTION OF THE FIGURES




The invention may be better understood with reference to the following figures and detailed description. The components in the figures are not necessarily to scale, emphasis being placed upon illustrating the principles of the invention. Moreover, like reference numerals in the figures designate corresponding parts throughout the different views.





FIG. 1

is a schematic diagram of an image-forming machine having a fuser station.





FIG. 2

is a side view of a fuser station for the image-forming machine shown in FIG.


1


.





FIG. 3

is a front perspective view of an upper skive assembly for a fuser station in an image-forming machine according to a first embodiment.





FIG. 4

is a back perspective view of the upper skive assembly shown in FIG.


3


.





FIG. 5

is a side view of the upper skive assembly shown in FIG.


3


.





FIG. 6

is a back perspective view of an upper skive assembly for a fuser station in an image-forming machine according to a second embodiment.





FIG. 7

is a front perspective view of the upper skive assembly shown in FIG.


6


.





FIG. 8

is a side view of the upper skive assembly shown in FIG.


6


.





FIG. 9

is a first close-up bottom perspective view of the upper skive assembly shown in FIG.


6


.





FIG. 10

is a second close-up bottom perspective view of the upper skive assembly shown in FIG.


6


.





FIG. 11

is a close-up top perspective view of the upper skive assembly shown in FIG.


6


.





FIGS. 12A and 12B

are close-up bottom views of a finger portion for the upper skive assembly shown in FIG.


6


: in which,

FIG. 12A

shows a tab section; and

FIG. 12B

does not show a tab section.





FIG. 13

is a side view of a fuser station for an image-forming machine according to the prior art.





FIG. 14

is a front perspective view of an upper skive assembly for a fuser station in an image-forming machine according to the prior art.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS





FIG. 1

is a representative schematic diagram of an image-forming machine


100


having a fuser station


118


. The image-forming machine


100


may be a copy machine, a facsimile machine, an electrophotographic image-forming machine, and the like. Along with the fuser station


118


, the image-forming machine


100


may include a photoconductor


102


, support rollers


104


, a motor driven roller


106


, a primary charger


108


, an exposure machine


110


, a toning station


112


, a transfer charger


114


, a cleaner


120


, related equipment, accessories, and the like. The related equipment and accessories may be a feeder


116


, a discharge tray (not shown), a logic and control circuit (not shown), a user interface (not shown), an inverter (not shown), a housing (not shown), and the like. The feeder


116


provides sheets of paper or medium. The image-forming machine


100


may have other equipment such as an inserter (not shown) and a finisher (not shown). While particular configurations and arrangements are shown, other configurations and arrangements may be used including those with other and additional components.




In one aspect, the photoconductor


102


is operatively mounted on the support rollers


104


and the motor driven roller


106


, which moves the photoconductor


102


in the direction indicated by arrow A. The primary charger


108


, the exposure machine


110


, the toning station


112


, the transfer charger


114


, the fuser station


118


, and the cleaner


120


are operatively disposed adjacent to the photoconductor


102


. The feeder


116


is operatively disposed to provide a sheet S of paper or other medium to the transfer charger


114


. Multiple sheets may be process in this manner or the like. The photoconductor


102


has a belt and roller-mounted configuration and may have a drum or other suitable configuration. The housing supports and protects various components of the image-forming machine


100


, which may be integrated with or part of the housing.




In use, the primary charger


108


electrostatically charges a frame on the photoconductor


102


. The exposure machine


110


optically exposes and forms an electrostatic image on the frame. The toning station


112


applies toner onto the frame. The toner has a charge to adhere to the electrostatic image. The transfer charger


114


transfers the toner from the frame onto a sheet from the feeder


116


. The fuser station


118


receives the sheet from the transfer charger


114


and fuses the toner onto the sheet. The sheet exits the image-forming equipment.





FIG. 2

is a representative side view of the fuser station


118


with a vented skive assembly for the image-forming machine


100


shown in FIG.


1


. In one aspect, the fuser station


118


has a pressure roller


122


and a fuser roller


124


. The pressure roller


122


and the fuser roller


124


are essentially the same length and are disposed longitudinally to form a nip or pinch region in the area between the rollers. The pressure roller


122


rotates counterclockwise as indicated by the arrow A. The fuser roller


124


rotates clockwise as indicated by arrow B. One or more heater rollers (not shown) heat the fuser roller


124


. Other heating devices may heat the fuser roller. The pressure roller


122


also may be heated. The fuser station


118


may have other configurations including other rollers.




The vented skive assembly removes and guides the sheet S away from the pressure and fuser rollers


122


and


124


. In one aspect, the vented skive assembly comprises a lower skive assembly


126


and an upper skive assembly


128


. The vented skive assembly may comprise other configurations including other upper and lower skive assemblies and may comprise either of the upper and lower skive assemblies individually. The lower and upper skive assemblies


126


and


128


may be interchanged. In this aspect, the upper and lower skive assemblies


126


and


128


have essentially the same length and are positioned in the fuser station


118


essentially longitudinal to the nip region; i.e., essentially longitudinal to the pressure and fuser rollers


122


and


124


.




In this aspect, the upper skive assembly


128


has one or more finger portions


132


that project toward the nip region. For orientation purposes, the front


128




a


of the upper skive assembly


128


faces the fuser and pressure rollers


122


and


124


. The back


128




b


of the upper skive assembly


128


faces away from the fuser and pressure rolls


122


and


124


. The bottom


128




c


of the upper skive assembly


128


faces the lower skive assembly


126


and also faces a sheet as it passes through the upper and lower skive assemblies


128


and


126


. The top


128




d


of the upper skive assembly


128


faces away from the lower skive assembly


126


and faces away from a sheet as it passes through the upper and lower skive assemblies


128


and


126


.




The fuser station


118


causes toner to fix or adhere to the sheet. In this fixing process, a sheet passes through the pressure and fuser rollers


122


and


124


in a sheet direction indicated by arrow C. For orientation purposes, the sheet S has a leading edge and a trailing edge. The leading edge passes through the nip region first. The trailing edge passes through the nip region last. The sheet also has side edges, which extend from the leading edge to the trailing edge. The sheet may have a rectangular or square shape, in which the side edges extend transversely between the leading and trailing edges.




As the sheet passes through the rollers


122


and


124


, the constriction of the nip region presses the toner onto the surface of the sheet. At essentially the same time, the fuser roller


124


transfers heat onto the sheet, causing the toner to fuse to the sheet. The counter-rotation of the rollers


122


and


124


pulls the sheet through the nip region. The leading edge of the sheet is directed into a guide path between the upper and lower skive assemblies


128


and


126


. However, the constriction and pressure of the rollers


122


and


124


and the heating of the toner in the nip region may cause the sheet to stick or otherwise attach to the pressure roller


122


. If the sheet is stuck or attached to the pressure roller


122


, the finger portions


132


catch or engage the leading edge of the sheet as it advances out of the nip region. The finger portions


132


guide or direct the leading edge into the guide path between the upper and lower skive assemblies


128


and


126


, thus pulling the sheet away from the pressure roller


122


as the sheet moves out of the nip region.




The fixing process is done at a fixing temperature of about 355° F. However, the process may be done at other temperatures suitable for the toner, the paper or other medium, and the components of the image-forming machine


100


. The fixing temperature may remain constant and may vary. In one aspect, the fixing temperature is in the range of about 300° F. through about 400° F. At these temperatures, water evaporates or is driven out of the sheet in the form of water vapor.





FIGS. 3-5

are representative views of an upper skive assembly


228


for a fuser station in an image-forming machine according to a first embodiment. In these figures, like reference numerals designate corresponding parts in these figures and in the image-forming machine described in

FIGS. 1-2

. The corresponding parts have similar functions and may be interchanged.

FIG. 3

is a front perspective view of the upper skive assembly


228


.

FIG. 4

is a back perspective view of the upper skive assembly


228


.

FIG. 5

is a side view of the upper skive assembly


228


. For orientation purposes, the upper skive assembly


228


has a front


228




a,


a back


228




b,


a bottom


228




c,


and a top


228




d.


The arrow C indicates the sheet direction of the sheet S through the fuser station. The upper skive assembly


228


may have other components such as mounting brackets (not shown), support members (not shown), and the like. The upper skive assembly


228


may be made from metal, such as steel, and any other material suitable to provide the structural support and other properties needed for removing sheets from the pressure roller in the fuser station. The upper skive assembly


228


may have other shapes and configurations.




The upper skive assembly


228


may have finger portions


232


connected along the front of a support member


238


. There may be five finger portions


232


. However, there may be only one finger portion or other multiples of finger portions. The finger portions


232


may be combined to form a single finger assembly (not shown) or groups of finger subassemblies (not shown). Each finger portion


232


has rib sections


236


connected to a base section


240


, which may form a single part or multiple parts. The rib sections


236


may connect directly to the support member


238


, in which case the base sections


240


would not be necessary. The base sections


240


are configured and connected to the support member


238


such that, when the upper skive assembly


228


is mounted on a fuser station, the base sections


240


form a guide path with the lower skive assembly (not shown) for a sheet to follow when it exits the pressure and fuser rollers. In one aspect, each base section


240


has a plate-like structure, which may be planar, angular, circular, or some other configuration. The base sections


240


may be connected to the support member


238


at an angle or curved position to the guide path. The angle may be chosen to correspond with a desired direction of the sheet as it exits the fuser and pressure rollers.




The finger portions


232


are configured and connected to the support member


238


such that, when the upper skive assembly


228


is mounted on a fuser station, the rib sections


236


project toward the nip region of the fuser and pressure rollers. If a sheet sticks to the pressure roller, the rib sections


236


are positioned to catch the leading edge of the sheet as it advances out of the nip region. The sheet then pulls away from the pressure roller as the sheet moves out of the nip region. The rib sections


236


guide the leading edge of the sheet toward the base sections


240


and onto the guide path between the upper and lower skive assemblies.




In this aspect, the rib sections


236


extend from the base sections


240


passing the front


228




a


of the upper skive assembly


228


and projecting toward the nip region. The rib sections


236


turn back toward and connect to the support member


238


at the front


228




a


of the upper skive assembly


228


. The rib sections


236


may connect elsewhere on the support member


238


. In this aspect, the rib sections


236


have an angular shape. However, the rib sections


236


may have triangular, curved, multi-facetted, combination, and other configurations. The cross-section of the rib sections


236


may be rectangular, angular, square, circular, and other configurations.




The rib sections


236


form slots


234


in the finger portions


232


. The slots


234


are openings in which air may flow through the upper skive assembly


228


. In one aspect, the slots


234


are configured to provide an airflow pattern to reduce condensation on the upper skive assembly


228


. “Reduce condensation” includes partially or completely preventing or eliminating the condensation of water vapor on the skive assembly. The slots


234


may reduce condensation across the entire skive assembly or in a particular area or areas of the skive assembly. There may be only one slot to reduce condensation on one part of the skive assembly. The air may have various flow patterns. The airflow may be provided by the natural heat convection from the fuser roller, by the environmental system (not shown) for the image-forming machine, a combination, and the like. There may be two to four slots


234


on each finger portion


232


. However, there may be only one slot


234


or other multiples of slots


234


on each finger portion


232


. There may be one finger portion


232


essentially spanning the length of the support member


238


, where the one finger portion


232


has a plurality of slots


234


.




In one aspect, the slots


234


are formed vertically from the bottom


228




c


and are essentially aligned with the sheet direction. The slots


234


follow the rib sections


236


to the connection of the rib sections


236


with the support member


238


at the front


228




a.


The slots


234


may be formed horizontally or at an angle to the sheet direction. The slots also may have a spiral shape or another configuration. The slots


234


may be groups of holes (not shown) or other openings that form perforated sections (not shown) in the finger portions


232


. One or more of the slots


234


may extend into or through one or more of the base sections


240


. The slots


234


may be formed into groups of slots, where one group has one configuration and another group has another configuration. A first group of slots may be aligned or be aligned at an angle to the sheet direction. A second group of slots may be aligned at a different angle to the sheet direction.




Each of the openings created by the slots


234


has an open area along the surface of the finger portions


232


. The open areas may be combined to provide an total open area for the upper skive assembly


228


. Similarly, each of the rib sections


236


forms a closed area along the surface of the finger portions


232


. The closed areas may be combined to provide an total closed area for the upper skive assembly


228


. In one aspect, the ratio of the total open area of the slots


234


to the total closed area of the rib sections


236


is in the range of about 1:1 through about 6:1. The ratio of the total open area of the slots


234


to the total closed area of the rib sections


236


may be greater than about 6:1, in which case the rib sections


236


may have a more wire-like configuration. The ratio of the total open area of the slots


234


to the total closed area of the rib sections


236


may be less than about 1:1 as long as there is suitable airflow or an airflow pattern to reduce condensation on the upper skive assembly


228


. Increasing the throughput of the environmental system may improve the airflow. The open area of each slot


234


may be the same or may vary. The total open area may be evenly distributed and may vary across one or all of the finger portions


232


and across the upper skive assembly


228


. One finger portion may have narrow slots (not shown). Another finger portion may have wide slots (not shown). Yet another finger portion may have a combination of narrow slots and wide slots (not shown).




In one aspect, the support member


238


is configured and connected to the finger portions


232


such that, when the upper skive assembly


228


is mounted on a fuser station, the rib sections


236


and the base sections


240


are positioned as previously discussed. The support member


238


may be disposed essentially parallel to the nip region between the pressure and fuser rollers in a fuser station. The support member


238


may have a planar, rectangular shape. However, the support member


238


may have an angled, curved, another shape, a combination, and the like. The support member


238


may have any suitable thickness and dimensions and may be part of or form another part in the image-forming machine. The rib sections


236


may be connected to the front of the support member


238


and may connect directly to the bottom of the support member


238


. The connections with the rib sections


236


may form an essentially straight line, a curved line, another type of line, a combination of lines, and may not form any line. Also, the base section


240


may be connected along the bottom of the support member


238


. The connections with the base sections


240


may form an essentially straight line, a curved line, another type of line, a combination of lines, and may not form any line. One or more of the rib sections


236


and one or more of the base sections


240


may have the same connection with the support member


238


.





FIGS. 6-12

are representative views of an upper skive assembly


628


for a fuser station in an image-forming machine according to a second embodiment. In these figures, like reference numerals designate corresponding parts in these figures, the first embodiment described in

FIGS. 3-5

, and the image-forming machine described in

FIGS. 1-2

. The corresponding parts have similar functions and may be interchanged.





FIG. 6

is a back perspective view of the upper skive assembly


628


.

FIG. 7

is a front perspective view of the upper skive assembly


628


.

FIG. 8

is a side edge view of the upper skive assembly


628


.

FIG. 9

is a close-up bottom perspective view from one side edge of the upper skive assembly


628


.

FIG. 10

is a close-up bottom perspective view from the other side edge of the upper skive assembly


628


.

FIG. 11

is a close-up top view of the upper skive assembly


628


.

FIG. 12

shows close-up bottom views of a finger portion


732


of the upper skive assembly


628


.

FIG. 12A

includes a tab section


744


.

FIG. 12B

does not include the tab section.




For orientation purposes, the upper skive assembly


628


has a front


628




a,


a back


628




b,


a bottom


628




c,


and a top


628




d.


The arrow C indicates a sheet direction of a sheet through the fuser station. The upper skive assembly


628


may have other components. The upper skive assembly


628


may be made from metal such as steel and may be made of any suitable material. The upper skive assembly


628


may have other shapes and configurations.




The upper skive assembly


628


may have a finger assembly


630


, which includes an upper section


631


and finger portions


632


and


732


. The finger portions


632


and


732


have rib sections


636


and


736


and base sections


640


and


740


. The finger assembly


630


may be made from a single part. The finger assembly


630


is configured and connected to the support member


638


such that, when the upper skive assembly


628


is mounted on a fuser station, the rib sections


636


project toward the nip region of the fuser and pressure rollers. In this position, the rib sections


636


and


736


catch or engage the leading edge of a sheet as it advances out of the nip region. The sheet pulls away from the pressure roller as the sheet moves out of the nip region. The rib sections


636


and


736


guide or direct the leading edge toward the base sections


640


and


740


and onto the guide path between the upper and lower skive assemblies.




The finger portions


632


and


732


are arranged along the front of the support member


638


. The finger portions


632


and


732


are connected to the upper section


631


, which connects to the support member


638


. The finger portions


632


and


732


may be connected separately to the support member


638


and may be combined into multiple subassemblies (not shown) connected to the support member


638


. While this embodiment shows eight finger portions


632


and


732


, there may be only one finger portion or other multiples of finger portions.




Each finger portion


632


and


732


has multiple rib sections


636


and


736


connected to a base section


640


and


740


. The rib sections


636


and


736


and the base section


640


and


740


may form a single part or multiple parts. The base sections


640


and


740


are configured and connected to the support member


638


such that, when the upper skive assembly


628


is mounted on a fuser station, the base sections


640


and


740


form a guide path with the lower skive assembly (not shown) for the sheet to follow when it exits the pressure and fuser rollers. The rib sections


636


and


736


may connect directly to the bottom of the support member


638


with the base sections


640


and


740


. In one aspect, each base section


640


and


740


has a plate-like structure, which may be planar, angular, circular, or some other configuration. One or more of the base sections


640


and


740


may form a tail or an otherwise uneven portion along the back


628




b


of the upper skive assembly


628


. The tail portion may curve or angle away from the guide path. The base sections


640


and


740


may be connected to the support member


638


at an angle or curved position to the guide path. The angle or curve may be chosen to correspond with a desired direction of the sheet as it exits the fuser and pressure rollers.




In one aspect, the rib sections


636


and


736


extend from the base sections


640


and


740


passing the front


628




a


of the upper skive assembly


628


and project toward the nip region. The rib sections


636


and


736


then turn back toward the support member


638


at the front of the upper skive assembly


628


. The rib sections


636


and


736


connect to or form the upper section


631


, which connects to the front of the support member


638


. The upper section


631


may connect elsewhere on the support member


638


. The rib sections


636


and


736


may connect directly to the support member


638


without the upper section


631


. The rib sections


636


and


736


may have a triangular shape and may be angled, curved, multi-facetted, a combination, and other configurations. The cross-section of the rib sections


636


and


736


may be square, angular, and the like.




The rib sections


636


and


736


form slots


634


and


734


in the finger portions


632


and


732


. The slots


634


and


734


are openings in which air may flow through the upper skive assembly. The airflow may have various patterns as previously discussed. The airflow may be provided by the natural heat convection from the fuser roller, by the environmental system (not shown) for the image-forming machine, a combination, and the like. There may be one to six slots


634


and


734


on each finger portion


632


and


732


. However, each finger portion


632


and


732


may have one slot


634


and


732


or other multiples of slots


634


and


734


. There may be one and other multiples of the finger portions


632


and


732


. There may be one finger portion


632


and


732


essentially spanning the length of the support member


638


, where the one finger portion


632


and


732


has a plurality of slots


634


and


734


.




The slots


634


and


734


are configured to provide an airflow pattern to reduce condensation on the upper skive assembly


628


as previously discussed. The slots


634


and


734


may be formed vertically from the bottom of the upper skive assembly


628


and are aligned essentially with the sheet direction C. The slots


634


and


734


follow the rib sections


636


and


736


to the connection with the upper section


631


. The slots


634


and


734


may be formed horizontal, angular, and with other configurations in relation to the sheet direction C. The slots


634


and


734


may be groups of holes (not shown) or other openings that form perforated sections (not shown) in the finger portions


632


. One or more of the slots may extend into or through one or more of the base sections


640


and


740


. One or-more of the slots may extend into and through the upper section


631


.




Each of the openings created by the slots


634


and


734


has an open area along the surface of the finger portions


632


and


732


. The open areas may be combined to provide an total open area for the upper skive assembly


628


. Similarly, each of the rib sections


636


and


736


forms a closed area along the surface of the finger portions


632


and


732


. The closed areas may be combined to provide an total closed area for the upper skive assembly


628


. In one aspect, the ratio of the total open area of the slots


634


and


734


to the total closed area of the rib sections


636


and


736


is in the range of about 1:1 through about 6:1. The ratio of the total open area of the slots


634


and


734


to the total closed area of the rib sections


636


and


736


may be greater than about 6:1, in which case the rib sections


636


and


736


may have a more wire-like configuration. The ratio of the total open area of the slots


634


and


734


to the total closed area of the rib sections


636


and


736


may be less than about 1:1 as long as there is suitable airflow or an airflow pattern to reduce condensation on the upper skive assembly


228


. Increasing the throughput of the environmental system may improve the airflow. The open area of each slot


634


and


734


may be the same or may vary. The total open area may be evenly distributed and may vary across one or all of the finger portions


632


and


732


and across the upper skive assembly


628


. One finger portion may have narrow slots (not shown). Another finger portion may have wide slots (not shown). Yet another finger portion may have a combination of narrow slots and wide slots (not shown).




The support member


638


is configured and connected to the finger assembly


630


such that, when the upper skive assembly


628


is mounted on a fuser station, the rib sections


636


and


736


and the base sections


640


and


740


are positioned as previously discussed. The support member


638


may be disposed essentially parallel to the nip region between the pressure and fuser rollers in a fuser station. The support member


638


may have a planar, rectangular shape. However, the support member


638


may have an angled, curved, another shape, a combination, and the like. The support member


638


may have any suitable thickness and dimensions and may be part of or form another part in the image-forming machine. The upper section


631


of the finger assembly


630


may connect to the front of the support member


638


.




The base sections


640


and


740


may connect along the bottom of the support member


638


. In one aspect, the support member


638


has a ledge portion


642


. The ledge portion


642


horizontally connects to one or more of the base sections


640


and


740


. The support member


638


may be connected to one or more of the base sections


640


and


740


without the ledge portion


642


, and by other means. The connections with the base sections


640


and


740


may form an essentially straight line, a curved line, another type of line, a combination of lines, and may not form any line. The support member


638


also may connect with one or more of the rib sections


636


and


736


on the bottom


628




c


of the upper skive assembly


628


at or near the connection of the support member


638


with one or more of the base sections


640


and


736


.




In one aspect, the finger portions


732


may have an insert prevention device operatively disposed in each of the slots


734


. The finger portions


632


do not have the insert prevention device disposed in each of the slots


634


. However, any or all of the slots


634


each may have the insert prevention device. There may be different configurations of finger portions


632


and


732


that have the insert prevention device in one or more of the slots. One or more of the slots


634


and


734


may have the insert prevent device.




The image-forming machine may be designed to center align the sheets with the upper skive assembly


638


. When sheets are center aligned, the center of each sheet passes along the center of the upper skive assembly. Accordingly, the position of the sheet side edges along the upper skive assembly


628


varies with the sheet size. In one aspect, the finger portions


732


extend to cover an area on each side edge of the upper skive assembly corresponding to the edge locations of the expected or planned sheet sizes used in the image-forming machine. The number of finger portions


732


on each side edge of the upper skive assembly


628


may be the same and may vary. If smaller sheets are used, there may be more finger portions


732


.




The sheets may be edge aligned—the same side edge of each sheet passes along an alignment edge on the upper skive assembly


628


. The position of the side edge along the alignment edge is essentially the same regardless of the sheet size. However, the position of the other side edge along the upper skive assembly varies with the sheet size. The number of finger portions


732


on each side edge of the upper skive assembly


628


may be different. There may be one or two finger portions


732


along the alignment edge with more finger portions


732


along the side edge opposite the alignment edge. The additional finger portions


732


would accommodate sheets of different dimensions. In an upper skive assembly with eight finger portions


632


and


732


; there may be two finger portions


732


on the alignment edge side edge, followed by two finger portions


632


, followed by four finger portions


732


on the other side edge.




The insert prevention device prevents and corrects a sheet stubbing a slot as the sheet passes the upper skive assembly


628


. “Stubbing” includes any manner of the sheet entering, engaging, jamming, and catching on or in a slot, especially on a rib or base section, and the like. If the side edge of a sheet enters a slot, the leading edge of the sheet may hit the base section or other part as the sheet passes across the upper skive assembly


628


. The stubbing may cause the sheet to fold, bend, become entangled, tear, and the like. The insert prevention device may reduce or eliminate the ability of the side edge to enter a slot. If a side edge should stub a slot, the insert prevention device may remove or otherwise disengage the sheet from a slot and any adjacent rib and base sections.




In one aspect, the insert prevention device includes a tab section


744


and an angled slot portion


745


(see

FIGS. 8

,


12


A, and


12


B). The insert prevention device may include one of the tab section


744


and the angled slot portion


745


. The insert prevention device may include other configurations suitable to prevent and correct for stubbing. The insertion prevention device may be integrally formed with the base section


740


and at least one of the rib sections


736


from the same piece. “Integrally formed” includes cutting, bending, and shaping a single piece such as a metal plate or other suitably shaped material.




In this aspect, the tab section


744


extends from the base section


740


into the slot


734


. The connection of the tab section


744


with the base section


740


preferably is closer to the bottom and back of the upper skive assembly


628


. The portion of the tab section


744


extending into the slot


734


preferably is closer to the top and front of the upper skive assembly. The tab section


744


may be formed from at least one of the base section


740


and one or more rib sections


736


. The tab section


744


may be cutout except for the connection with the base section


740


. In one aspect, the tab section


744


forms a smooth transition or connection with the base section


740


. The tab section


744


may be essentially the same size or slightly smaller than the angled slot portion


745


. The exterior of the tab section


744


may be the same or have a similar configuration as the angled slot portion


745


. The base section


740


, tab section


744


, and rib sections


736


may be the same piece or part of the same piece such as the finger assembly


630


.




In this aspect, the tab section


744


forms an angle α with the base section


740


or the bottom


628




c


of the upper skive assembly


628


(see FIG.


8


). The tab section


744


may form the angle α with on or a portion of a rib section or another part that is essentially parallel to the sheet direction. The angle α may be selected to guide the leading edge of a sheet out of the slot


734


. In one aspect, the angle α is greater than about five degrees. In another aspect, the angle α is the range of about 15 degrees through about 45 degrees. In yet another aspect, the angle α is about 30 degrees.




The angled slot portion


745


is formed by a first slot edge


746


of a first rib section


736




a


and a second slot edge


748


of a rib section


736




b


(see FIGS.


12


A and


12


B). The first slot edge


746


has a first straight segment


750


and a first angled segment


752


. The second slot edge


748


has a second straight segment


754


and a second angled segment


756


. In one aspect, the first and second straight segments


750


and


754


are essentially parallel to the sheet direction C. However, the first and second straight segments


750


and


754


may be at an angle to the sheet direction C and at an angle to each other. In this aspect, the first and second angled segments


752


and


756


slant toward the rib sections


736




a


and


736




b,


respectively. However, one or both of the first and second angled segments


752


and


756


may slant toward the slot


734


. The first and second angled segments


752


and


756


may be parallel. Both slot edges


746


and


748


may not have any straight segments


750


and


754


. One slot edge may have straight and angled segments while the other slot edge has one of straight and angled segments.




The angled segments


752


and


756


form angles β and β′ with the straight segments


750


and


754


, respectively. One or both of the angle segments


752


and


756


may include part or all of the edge sections


746


and


748


, respectively. In which case there would not be one or both of the straight segments


750


and


754


. The angles β and β′ may be the same and may be different for one or more slots


734


. One or both of the angles β and β′ may be configured to prevent a sheet from stubbing. In one aspect, one or both of the angles β and β′ is greater than about two degrees. In another aspect, one or both of the angles β and β′ is in the range of about 5 degrees through about 20 degrees. In yet another aspect, one or both of the angles β and β′ is about 13 degrees.




In one aspect, the tab section


744


and the angled slot portion


745


prevent, reduce, and correct, individually and in combination, the stubbing of a sheet in the slot


734


. As the sheet passes across the upper skive assembly


628


, the side edges may pass across one or more of the angled slot portions


745


. Because the angled slot portions


745


crosses the side edges at the angles β and β′, it is very difficult if not impossible for the sheet to enter the angled slot portions


745


. If a side edge enters a slot


745


, the portion of the leading edge in the slot


745


engages the tab section


744


as the sheet passes across the upper skive assembly


628


. The tab section


744


essentially guides the leading edge out of the slot


745


and back into the guide path between the upper and lower skive assemblies.




Various embodiments of the invention have been described and illustrated. However, the description and illustrations are by way of example only. Many more embodiments and implementations are possible within the scope of this invention and will be apparent to those of ordinary skill in the art. Therefore, the invention is not limited to the specific details, representative embodiments, and illustrated examples in this description. Accordingly, the invention is not to be restricted except in light as necessitated by the accompanying claims and their equivalents.



Claims
  • 1. A skive assembly for a fuser station in an image-forming machine, comprising:a support member; and a plurality of rib sections connected to the support member, the plurality of rib sections forming at least one slot, where the at least one slot is configured to provide an airflow pattern to reduce condensation on the skive assembly, where the at least one slot comprises at least one first slot and at least one second slot, the at least one first slot at an angle to the at least one second slot.
  • 2. A skive assembly for a fuser station in an image-forming machine, comprising:a support member; and a plurality of rib sections connected to the support member, the plurality of rib sections forming at least one slot, where the at least one slot is configured to provide an airflow pattern to reduce condensation on the skive assembly, where the at least one slot comprises at least one first slot and at least one second slot, and where the at least one first slot is larger than the at least one second slot.
  • 3. A skive assembly for a fuser station in an image-forming machine, comprising:a support member; and a plurality of rib sections connected to the support member, the plurality of rib sections forming at least one slot, where the at least one slot is configured to provide an airflow pattern to reduce condensation on the skive assembly, further comprising an insert prevention device disposed in the at least on slot.
  • 4. A skive assembly according to claim 3, where the at least one slot comprises at least one first slot and at least one second slot, where the insert prevention device is disposed in the at least one first slot.
  • 5. A skive assembly according to claim 3, where the insert prevention device is at least one of a tab section and an angled slot portion.
  • 6. A skive assembly according to claim 5, where the tab section and the angled slot portion are integrally formed from one piece comprising the base section and at least one rib section.
  • 7. A skive assembly according to claim 5, where the tab section is disposed to guide an edge of a sheet out of the at least one slot.
  • 8. A skive assembly according to claim 5, further comprising a base section connected to the support member and to the plurality of ribs, where the tab section is connected to one of the base section and at least one of the rib sections, where the tab section extends into the slot.
  • 9. A skive assembly according to claim 8, where the tab section forms an angle α with the base section.
  • 10. A skive assembly according to claim 5, where the plurality of rib sections comprises a first rib section and a second rib section, the first rib section having a first slot edge, the second rib section having a second slot edge, the first and second slot edges forming the angled slot portion.
  • 11. A skive assembly according to claim 10, where at least one of the first slot edge and the second slot edge has a straight segment and an angled segment.
  • 12. A skive assembly according to claim 10,where the plurality of rib sections comprises a first rib section and a second rib section, the first rib section having a first slot edge, the second rib section having a second slot edge, where the first slot edge has a first straight segment at an angle β to a first angled segment, where the second slot edge has a straight segment at an angle β′ to a second angled segment, and where the first and second angled segments form the angled slot portion.
  • 13. A skive assembly according to claim 12, where at least one of angle β and angle β′ is greater than about two degrees.
  • 14. A skive assembly according to claim 12, where at least one of angle β and angle β′ is in the range of about five degrees through about 20 degrees.
  • 15. A skive assembly according to claim 12, where at least one of angle β and angle β′ is about 13 degrees.
  • 16. A skive assembly for a fuser station in an image-forming machine, comprising:a support member; and a plurality of rib sections connected to the support member, the plurality of rib sections forming at least one slot, where the at least one slot is configured to provide an airflow pattern to reduce condensation on the skive assembly, further comprising an insert prevention device disposed in the at least one slot, where the insert prevention device is a tab section, further comprising a base section connected to the support member and to the plurality of ribs, where the tab section is connected to one of the base section and at least one of the rib sections, where the tab section extends into the slot, where the tab section forms an angle α with one of the rib sections.
  • 17. A skive assembly according to claim 16, where the angle α is greater than about five degrees.
  • 18. A skive assembly according to claim 16, where the angle α is in the range of about 15 degrees through about 45 degrees.
  • 19. A skive assembly according to claim 16 where the angle α is about 30 degrees.
  • 20. A vented fuser station for an imaging-forming machine, comprising:a pressure roller; a fuser roller disposed to form a nip region with the pressure roller; and a skive assembly operatively disposed to engage a sheet advancing out of the nip region in a sheet direction, where the skive assembly has at least one finger portion with a plurality of rib sections forming at least one slot, where the plurality of rib sections projects from the skive assembly toward the nip region, and where the at least one slot is configured to provide an airflow pattern that reduces condensation on the skive assembly, where the at least one finger portion further comprises an insert prevention device disposed in the at least one slot.
  • 21. A vented fuser station for an image-forming machine, comprising:a pressure roller; a fuser roller disposed to form a nip region with the pressure roller; and a skive assembly operatively disposed to engage a sheet advancing out of the nip region in a sheet direction, where the skive assembly has at least one finger portion with a plurality of rib sections forming at least one slot, where the plurality of rib sections projects from the skive assembly toward the nip region, and where the at least one slot is configured to provide an airflow pattern that reduces condensation on the skive assembly, where an insert prevention device comprises at least one of a tab section and an angled slot portion.
  • 22. A vented fuser station according to claim 21,where the tab section is connected to one of the base section and at least one rib section, where the tab section extends into the slot, and where the tab section forms a first angle with the base section.
  • 23. A vented fuser station according to claim 21, where the tab section forms a first angle with the sheet direction.
  • 24. A vented fuser station according to claim 23, where the first angle is greater than about five degrees.
  • 25. A vented fuser station according to claim 21, where the angled slot portion is formed by first and second slot edges, the first slot edge provided by a first rib section, the second slot provided by a second rib section, and where at least one of the first and second slot edges has a straight segment at a second angle to an angled segment.
  • 26. A vented fuser station according to claim 21, where the plurality of rib sections has a first rib section and a second rib section, the first rib section having a first straight segment and a first angled segment, the second rib section having a second straight segment and a second angled segment, where the angled slot portion is formed by first and second angled segments.
  • 27. A vented fuser station according to claim 26, where at least one of the straight segments forms a second angle with at least one of the angled segments.
  • 28. A vented fuser station according to claim 27, where the second angle is greater than about two degrees.
  • 29. A vented fuser station in an image-forming machine, comprising:a pressure roller; a fuser roller disposed to form a nip region with the pressure roller; and a skive assembly operatively disposed to engage a sheet advancing out of the nip region in a sheet direction, where the skive assembly has a plurality of rib sections forming a plurality of slots, where the plurality of slots are configured to provide an airflow pattern that reduces condensation on the skive assembly, where the skive assembly further comprises a support member, where a finger assembly has an upper section connected to the support member, where the finger assembly has a base section connected to the support member, and where the plurality of rib sections are connected to the base section and to the upper section.
  • 30. A vented fuser station in an image-forming machine, comprising:a pressure roller; a fuser roller disposed to form a nip region with the pressure roller; and a skive assembly operatively disposed to engage a sheet advancing out of the nip region in a sheet direction, where the skive assembly has a plurality of rib sections forming a plurality of slots, where the plurality of slots are configured to provide an airflow pattern that reduces condensation on the skive assembly, where the plurality of slots comprises a first group of slots and a second group of slots, where the first group of slots is essentially aligned with the sheet direction, and where the second group of slots is at an angle with the sheet direction.
  • 31. A vented fuser station according to claim 30, where one of the first and second groups comprises at least one slot.
  • 32. A vented fuser station in an image-forming machine, comprising:a pressure roller; a fuser roller disposed to form a nip region with the pressure roller; and a skive assembly operatively disposed to engage a sheet advancing out of the nip region in a sheet direction, where the skive assembly has a plurality of rib sections forming a plurality of slots, where the plurality of slots are configured to provide an airflow pattern that reduces condensation on the skive assembly, where the plurality of slots comprises a first group of slots and a second group of slots, and where each slot in the first group of slots has an inset prevention device.
  • 33. A vented fuser station according to claim 32, where the first group of slots is disposed in at least one area corresponding to a side edge position of the sheet.
  • 34. A vented fuser station according to claim 33, where a sheet passing through the vented fuser station is center aligned.
  • 35. A vented fuser station according to claim 33 where a sheet passing through the vented fuser station is edge aligned.
  • 36. A vented fuser station in an image-forming machine, comprising:a pressure roller; a fuser roller disposed to form a nip region with the pressure roller, and a skive assembly operatively disposed to engage a sheet advancing out of the nip region in a sheet direction, where the skive assembly has a plurality of rib sections forming a plurality of slots, where the plurality of slots are configured to provide an airflow pattern that reduces condensation on the skive assembly, where the skive assembly has an insert prevention device disposed in at least one slot of the plurality of slots.
  • 37. A vented fuser station according to claim 36, where the insert prevention device comprises at least one of a tab section and an angled slot portion.
  • 38. A vented fuser station according to claim 37, where the plurality of rib sections are connected to at least one base section, where the tab section forms a first angle with the base section.
  • 39. A vented fuser station according to claim 37, where the tab section forms a first angle with the sheet direction.
  • 40. A vented fuser station according to claim 39, where the first angle is greater than about five degrees.
  • 41. A vented fuser station according to claim 37, where the angled slot portion is formed by first and second slot edges, the first slot edge provided by a first rib section, the second slot edge provided by a second rib section, and where at least one of the first and second slot edges has a straight segment at a second angle to an angled segment.
  • 42. A vented fuser station according to claim 37,where the plurality of rib sections comprises a first rib section and a second rib section, the first rib section having a first slot edge, the second rib section having a second slot edge, where the first slot edge has a first straight segment at a second angle to a first angled segment, where the second slot edge has a straight segment at a second angel to a second angled segment, and where the first and second angled segments form the angled slot portion.
  • 43. A vented fuser station according to claim 42, where the second angle is greater than about two degrees.
  • 44. An image-forming machine with a vented fuser station, comprising:a photoconductor; a primary charger operatively disposed to electrostatically charge the photoconductor; an exposure machine operatively disposed to optically expose and form an electrostatic image on the photoconductor; a toning station operatively disposed to apply toner on the photoconductor, the toner having a charge to adhere to the electrostatic image; a transfer charger operatively disposed adjacent to the photoconductor, the transfer charger to transfer the toner from the photoconductor onto a sheet; and a fuser station operatively disposed to receive the sheet from the transfer charger, the fuser station to fuse the toner onto the sheet, where the fuser station includes, a pressure roller; a fuser roller disposed to form a nip region with the pressure roller; and a skive assembly operatively disposed to engage the sheet advancing out of the nip region in a sheet direction, the skive assembly having at least one finger portion with a plurality of rib sections forming at least one slot, where the at least one slot is configured to provide an airflow pattern that reduces condensation on the skive assembly, where the at least one finger portion further comprises an insert prevention device disposed in the at least one slot.
  • 45. An image-forming machine-according to claim 44, where the insert prevention device comprises at least one of a tab section and an angled slot portion.
  • 46. An image forming machine according to claim 45, where the tab section forms a first angle with the sheet direction.
  • 47. An image-forming machine to claim 46, where the first angle is greater than about five degrees.
  • 48. An image-forming machine according to claim 45, where the plurality of rib sections has a first rib section and a second rib section, the first rib section having a first straight segment and a first angled segment, the second rib section having a second straight segment and a second angled segment, where the angled slot portion is formed by first and second angled segments.
  • 49. An image forming machine according to claim 45, where the angled slot portion is formed by first and second slot edges, the first slot edge provided by a first rib section, the second slot provided by a second rib section, and where at least one of the first and second slot edges has a straight segment at a second angle to an angled segment.
  • 50. An image-forming machine according to claim 49, where the second angle is greater than about two degrees.
Foreign Referenced Citations (3)
Number Date Country
54-65550 May 1979 JP
6-43772 Feb 1994 JP
6-118818 Apr 1994 JP