EP0470860B1 - Electrophotographic reproduction method having improved fuser - Google Patents
Electrophotographic reproduction method having improved fuser Download PDFInfo
- Publication number
- EP0470860B1 EP0470860B1 EP91307358A EP91307358A EP0470860B1 EP 0470860 B1 EP0470860 B1 EP 0470860B1 EP 91307358 A EP91307358 A EP 91307358A EP 91307358 A EP91307358 A EP 91307358A EP 0470860 B1 EP0470860 B1 EP 0470860B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- pressure
- envelope
- nip
- transfer medium
- fuser
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/20—Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat
- G03G15/2003—Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat using heat
- G03G15/2014—Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat using heat using contact heat
- G03G15/2064—Apparatus for electrographic processes using a charge pattern for fixing, e.g. by using heat using heat using contact heat combined with pressure
Definitions
- This invention relates generally to electrophotographic reproduction apparatus, such as printers and copiers, which employ pressure for fusing a toned image onto a transfer medium.
- the invention more particularly concerns such apparatus in which, at least some of the time, images are fused to multiple ply transfer media such as envelopes.
- envelopes as well as cut sheets of paper can serve as the transfer media upon which information is printed.
- a printer typically employs a fuser which fuses a toner image of the information to be printed onto the paper or envelope.
- This fuser is usually made up of a fuser roller urged against a backup roller to form a pressure nip through which the transfer medium passes.
- the fuser roll is heated and has a relatively rigid outer surface, while the backup roll is softer and can be deformed somewhat to form the pressure nip.
- the present invention is characterised by the pressure at the pressure nip being substantially reduced for one or more brief intervals as the toned image on the transfer medium advances through the pressure nip.
- the fuser takes the form of a heated fuser roll and a backup roll biased together by a spring force to form a pressure nip, wherein the spring force is substantially reduced for one or more brief intervals during fusing.
- an electrophotographic printer 11 includes conventional imaging, development and transfer stations, designated collectively as 12, for placing a toner image on a transfer medium, such as an envelope 13.
- a transfer medium such as an envelope 13.
- the toner image on the envelope 13 is fused to the envelope by heat and pressure as it passes through a nip 14 between a fuser roll 16 and a backup roll 17, which are biased together by a spring 18.
- the fuser roll 16 is heated, such as by an internal heating lamp (not shown), and the fusing of the toner image on the envelope 13 as it passes through the nip 14 is a combination of heat and pressure fusing.
- the envelope 13 passes through the nip 14 and exits the printer 11 along the path designated 19.
- the force of the spring 18 urging the rolls 16 and 17 together is briefly removed several times during the fusing process. This permits the layers of the envelope to move relative to one another, substantially eliminating wrinkling and creasing of the envelope during fusing.
- a solenoid 21, operable to reduce the force of the spring 18, is momentarily activated several times as the envelope 13 passes through the nip 14.
- a sensor 22 senses the leading edge of the envelope 13 as the envelope has begun to pass through the nip 14.
- a function generator 23 briefly supplies a drive signal to a solenoid driver 24 to drive the solenoid 21. The drive signal is repeated several times as the envelope 13 passes through the fuser nip 14.
- the fuser rolls 16 and 17 are mounted at each end in a frame 31.
- the fuser roll 16 is a heated roll (heated by an interior bulb, not shown) having a hard exterior surface coated with Teflon or a similar material.
- the backup roll 17 has a yieldable surface, formed by a layer of material such as silicon rubber.
- the fuser roll 16 rotates within bearings 32 (shown partially broken away in Figure 2), 33 at each end of the fuser roll.
- the backup roll 17 has a metal spindle 34 rotatably supported in a ball bearing 36 at one end of the backup roll and a corresponding spindle 37 and ball bearing 38 at its other end.
- the spindles 34, 37 extend from a metal core (not shown) of the backup roll 17 which is surrounded by a silicon rubber layer, which contacts the fuser roll at the fuser nip.
- the fuser roll 16 is driven through a gear 42 secured to an end of the roll 16, by the printer drive (not shown).
- the backup roll 17 is loaded against the fuser roll 16 by the spring 18, and a spring 43 at the other end of the roll, and is driven by the fuser roll 16 through friction.
- the loading of the soft backup roll 17 against the fuser roll 16 causes a slight flattening of the backup roll 17 along its length, this deformation defining the fuser roll nip.
- the spring 18 is supported at its lower end by a plastic spring holder 44 (not shown in Figure 2) mounted on a portion 46 of the frame 31.
- the top of the spring 18 is received within a portion 47 of a plastic backup roll bearing housing 48, which carries the bearing 36 for the backup roll.
- the spring 43 is supported at its lower end on a spring holder 49 which is in turn supported on a portion 51 of the frame 31.
- a bearing housing 52 corresponding to the bearing housing 48, receives the upper end of the spring 43 and holds the backup roll bearing 38.
- the spring 43 urges the bearing housing 52 and bearing 38 upwardly, and the spring 18 urges the bearing housing 48 and the bearing 36 upwardly, thereby maintaining the pressure between the fuser roll 16 and the backup roll 17 at the fuser nip.
- envelopes are fed near the end of the fuser roll nip adjacent the spring 18 and the bearing 36.
- the pressure at the fuser roll nip at this end of the roll is momentarily relieved a number of times during the fusing of an envelope by exerting a force to overcome the force of the spring 18.
- the force to overcome the load of the spring 18 is supplied by the solenoid 21.
- the solenoid 21 is mounted on a bracket 53 which is attached to the frame 31.
- a pin 57 is attached to the core 54 of the solenoid 21.
- the pin 57 has an enlarged cylindrical head 58 received within a spring clip 59 mounted in the bearing housing 48.
- the pin 57 extends through an opening in the bottom portion 61 of the spring clip 59 and is free to tilt and translate slightly in any direction to accommodate misalignments of the solenoid 21 and the bearing housing 48.
- An envelope 13 is driven into the fuser nip by the printer paper feed system (not shown). As the envelope 13 passes through the nip, stresses are generated on the surface of the plys of paper of the envelope. These stresses typically cause a wave or bubble to be formed between the two layers of the envelope 13.
- the envelope engages an exit flag 62, activating a photosensor 63.
- the exit flag 62 and the photosensor 63 comprise the sensor 22 of Figure 1.
- a pulse from the activation of the photosensor 63 initiates the operation of the electrical driver circuit 24 and the function generator 23, which drive the solenoid 21.
- the solenoid allows the stresses on the envelope 13 to relax and permits bubbles to disappear. As the envelope 13 continues to move through the nip, more stresses are generated, and additional bubbles form. Therefore, after a selected time interval from the first actuation of the solenoid 21, the solenoid is again actuated to release the pressure between the fuser and backup rolls at the solenoid end of the rolls.
- the spacing between pulses of the solenoid is chosen in dependence upon various parameters. Stresses build up in envelopes at rates which depend upon the weight of the paper used to form the envelope (for example 60 g/m 2 , (16 pounds) to 90 g/m 2 (24 pounds)), and upon humidity conditions. In the illustrated fuser system, a spacing of approximately 38 to 51 mm (1.5 to 2 inches) between activations of the solenoid has been found to operate satisfactorily over a range of papers and for humidities normally encountered.
- upper and lower redrive rollers 64, 66 in the printer pull the envelope 13 along the path 19 as the envelope moves through and out of the fuser roll nip.
- the function generator 23 and driver 24 continue pulsing the solenoid as the envelope 13 is pulled along the paper path 19 until the trailing end of the envelope 13 exits the fuser nip.
- the current to the solenoid from the solenoid driver is controlled to rise and fall in a profile to be described subsequently.
- the current profile minimizes the dynamics of the backup roll/solenoid system, to provide quiet operation of the system.
- the duration of the solenoid pulse is such that separation between the fuser roll 16 and the backup roll 17 occurs for about 20 milliseconds. This provides time for the removal of the built-up stresses on the envelope 13 and yet maintains all portions of the envelope in the fuser nip under pressure for a sufficient time to provide adequate fuse quality of the toner image on the envelope.
- the envelope 13 enters the fuser nip at a velocity of 51 mm/s (two inches per second).
- a pressure load of approximately 6.8 kg (15 pounds) between the silicon rubber backup roll and the rigid fuser roll creates a deformation in the backup roll of approximately 2.54 mm (0.100 inches). Therefore, a given section of the envelope is in the fuser nip for about 50 milliseconds.
- the set-point temperature for the fuser roll nip is about 180°C. This pressure, heat and time is sufficient to attain good fuse quality over a wide range of operating conditions.
- a time interval sufficient to allow the leading edge of the envelope to reach the redrive rollers (64,66 in Figure 2) is allowed to pass before the first solenoid pulse is initiated.
- This delay interval causes the first pulse to occur approximately 38 mm (1.5 inches) from the leading edge of the envelope. This distance is designated X0 in Figure 4.
- the number of pulses and spacing therebetween are controlled by the function generator 23 in the illustrated form of the invention.
- a Wavetek 175 arbitrary waveform generator has been used for this purpose in one form of the invention.
- the function generator signals could be produced by the control software for the printer as part of the general printer control function.
- the pulses occur about one second apart, or each 51mm (two inches) along the envelope. This results in four pulses (as shown in Figure 4) for a number 10 (240mm (9 1/2 inch)) envelope, or three pulses for a number 7 3/4 (190mm (7 1/2 inch)) envelope.
- the length of the envelope can be automatically determined in the pre-fuser portion 12 of the printer 11 such as by measuring the time differential between making and breaking a paper sensor switch. This information can be used by the function generator 23 to determine the number of solenoid pulses required.
- the current pulse produced by the driver 24 tracks the voltage produced by the function generator 23, and takes the form shown in Figures 5 and 6.
- the current pulse to the solenoid 21 results in a displacement of the backup roll as shown in Figure 6.
- the motion required to separate the rolls in the illustrated form of the invention is approximately 0.762mm (0.030 inches) .
- the time of separation for proper function can be as short as 5 milliseconds and as long as 20 milliseconds. Between these limits, the envelope has sufficient time to "relax" and the fuse grade is not significantly affected.
- the heated fuser roll is a one millimeter thick aluminum tube having a 0.025mm (0.001 inch) thick coating of Teflon or Silverstone or the like.
- the backup roll is made up of a 10 millimeter diameter steel rod inside a 6 millimeter thick 25 dur SHORE A silicon rubber roll.
- the present invention provides a method of forming an image in an electrophotographic reproduction apparatus of the foregoing type in which creasing, folding, and treeing of envelopes is substantially reduced or eliminated.
Description
- This invention relates generally to electrophotographic reproduction apparatus, such as printers and copiers, which employ pressure for fusing a toned image onto a transfer medium. The invention more particularly concerns such apparatus in which, at least some of the time, images are fused to multiple ply transfer media such as envelopes.
- In the case of electrophotographic printers, for example, envelopes as well as cut sheets of paper can serve as the transfer media upon which information is printed. Such a printer typically employs a fuser which fuses a toner image of the information to be printed onto the paper or envelope. This fuser is usually made up of a fuser roller urged against a backup roller to form a pressure nip through which the transfer medium passes. In one form of fuser, the fuser roll is heated and has a relatively rigid outer surface, while the backup roll is softer and can be deformed somewhat to form the pressure nip.
- Normally, paper can be fed through this type of fuser without difficulty but envelopes tend to crease, fold, or form wrinkles (known as "treeing").
- The cause for these problems seems to be non-uniform feeding across the envelope surface due to the multiple ply nature of the envelope. Efforts to correct this problem have included the use of a segmented pressure roller and the employment of roller designs of different shapes. Another approach to solving the problem is to take advantage of the fact that there typically are non-printing zones at the leading and trailing edges of an envelope. In this approach, a reduced amount of pressure at the fuser nip is applied to the leading and trailing edges of the envelope so that the large force at the nip required for fusing is only applied where toner images will be placed on the envelope. This improves the situation somewhat, but creasing and treeing can still occur along the printable zone of an envelope. This type of arrangement is known from US-A-4,753,543.
- Thus it is known from US-A-4,753,543 to provide a method of forming an image on a transfer medium in an electrophotographic reproduction apparatus, comprising the steps of: developing a toned image and transferring that image to the said transfer medium; fusing the toned image to the transfer medium by advancing the transfer medium with the toned image thereon through a pressure nip.
- The present invention is characterised by the pressure at the pressure nip being substantially reduced for one or more brief intervals as the toned image on the transfer medium advances through the pressure nip.
- In one embodiment, the fuser takes the form of a heated fuser roll and a backup roll biased together by a spring force to form a pressure nip, wherein the spring force is substantially reduced for one or more brief intervals during fusing.
- An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:-
- Figure 1 is a diagrammatic illustration of an electrophotographic reproduction apparatus in accordance with the present invention;
- Figure 2 is an end view of a fuser mechanism, with portions removed, in accordance with the present invention;
- Figure 3 is a view, partially in section, of the fuser apparatus of Figure 2;
- Figure 4 is an illustration of the locations of reduced nip pressure in the fusing of an envelope in accordance with an embodiment of the present invention;
- Figure 5 is an illustration of a solenoid current waveform for each nip pressure reduction location; and
- Figure 6 is an illustration of fuser backup roll displacement relative to the solenoid current for each nip pressure reduction location.
- Turning first to Figure 1, an
electrophotographic printer 11 includes conventional imaging, development and transfer stations, designated collectively as 12, for placing a toner image on a transfer medium, such as anenvelope 13. The toner image on theenvelope 13 is fused to the envelope by heat and pressure as it passes through anip 14 between afuser roll 16 and abackup roll 17, which are biased together by aspring 18. - In the illustrated printer, the
fuser roll 16 is heated, such as by an internal heating lamp (not shown), and the fusing of the toner image on theenvelope 13 as it passes through thenip 14 is a combination of heat and pressure fusing. Theenvelope 13 passes through thenip 14 and exits theprinter 11 along the path designated 19. As theenvelope 13 moves through thenip 14, the force of thespring 18 urging therolls - In order to relieve the spring force, a
solenoid 21, operable to reduce the force of thespring 18, is momentarily activated several times as theenvelope 13 passes through thenip 14. To do this, asensor 22 senses the leading edge of theenvelope 13 as the envelope has begun to pass through thenip 14. In response to the sensing of the leading edge of theenvelope 13, afunction generator 23 briefly supplies a drive signal to asolenoid driver 24 to drive thesolenoid 21. The drive signal is repeated several times as theenvelope 13 passes through thefuser nip 14. - With reference now to Figures 2 and 3, and considering the
fuser rolls spring 18, andsolenoid 21 in more detail, thefuser rolls frame 31. Thefuser roll 16 is a heated roll (heated by an interior bulb, not shown) having a hard exterior surface coated with Teflon or a similar material. Thebackup roll 17 has a yieldable surface, formed by a layer of material such as silicon rubber. Thefuser roll 16 rotates within bearings 32 (shown partially broken away in Figure 2), 33 at each end of the fuser roll. Thebackup roll 17 has ametal spindle 34 rotatably supported in a ball bearing 36 at one end of the backup roll and acorresponding spindle 37 and ball bearing 38 at its other end. Thespindles backup roll 17 which is surrounded by a silicon rubber layer, which contacts the fuser roll at the fuser nip. - The
fuser roll 16 is driven through agear 42 secured to an end of theroll 16, by the printer drive (not shown). Thebackup roll 17 is loaded against thefuser roll 16 by thespring 18, and aspring 43 at the other end of the roll, and is driven by thefuser roll 16 through friction. The loading of thesoft backup roll 17 against thefuser roll 16 causes a slight flattening of thebackup roll 17 along its length, this deformation defining the fuser roll nip. - The
spring 18 is supported at its lower end by a plastic spring holder 44 (not shown in Figure 2) mounted on aportion 46 of theframe 31. The top of thespring 18 is received within aportion 47 of a plastic backuproll bearing housing 48, which carries thebearing 36 for the backup roll. - At the other end of the
rolls spring 43 is supported at its lower end on aspring holder 49 which is in turn supported on aportion 51 of theframe 31. Abearing housing 52, corresponding to the bearinghousing 48, receives the upper end of thespring 43 and holds the backup roll bearing 38. Thespring 43 urges the bearinghousing 52 and bearing 38 upwardly, and thespring 18 urges the bearinghousing 48 and thebearing 36 upwardly, thereby maintaining the pressure between thefuser roll 16 and thebackup roll 17 at the fuser nip. - In the illustrated printer, envelopes are fed near the end of the fuser roll nip adjacent the
spring 18 and thebearing 36. The pressure at the fuser roll nip at this end of the roll is momentarily relieved a number of times during the fusing of an envelope by exerting a force to overcome the force of thespring 18. - The force to overcome the load of the
spring 18 is supplied by thesolenoid 21. Thesolenoid 21 is mounted on abracket 53 which is attached to theframe 31. Apin 57 is attached to thecore 54 of thesolenoid 21. Thepin 57 has an enlargedcylindrical head 58 received within aspring clip 59 mounted in thebearing housing 48. Thepin 57 extends through an opening in thebottom portion 61 of thespring clip 59 and is free to tilt and translate slightly in any direction to accommodate misalignments of thesolenoid 21 and thebearing housing 48. - When the
solenoid 21 receives drive current, thepin 57 and bearinghousing 48 are pulled downwardly in opposition to the force of thespring 18, releasing the pressure to the fuser nip at the end of the fuser roll where envelopes pass and thesolenoid 21 is located. - An
envelope 13 is driven into the fuser nip by the printer paper feed system (not shown). As theenvelope 13 passes through the nip, stresses are generated on the surface of the plys of paper of the envelope. These stresses typically cause a wave or bubble to be formed between the two layers of theenvelope 13. - In the present printer, as the leading edge of the
envelope 13 exits the nip and continues down thepaper path 19, the envelope engages anexit flag 62, activating aphotosensor 63. Theexit flag 62 and thephotosensor 63 comprise thesensor 22 of Figure 1. A pulse from the activation of thephotosensor 63 initiates the operation of theelectrical driver circuit 24 and thefunction generator 23, which drive thesolenoid 21. - The activation of the solenoid allows the stresses on the
envelope 13 to relax and permits bubbles to disappear. As theenvelope 13 continues to move through the nip, more stresses are generated, and additional bubbles form. Therefore, after a selected time interval from the first actuation of thesolenoid 21, the solenoid is again actuated to release the pressure between the fuser and backup rolls at the solenoid end of the rolls. - In the present instance, the spacing between pulses of the solenoid is chosen in dependence upon various parameters. Stresses build up in envelopes at rates which depend upon the weight of the paper used to form the envelope (for example 60 g/m2, (16 pounds) to 90 g/m2 (24 pounds)), and upon humidity conditions. In the illustrated fuser system, a spacing of approximately 38 to 51 mm (1.5 to 2 inches) between activations of the solenoid has been found to operate satisfactorily over a range of papers and for humidities normally encountered.
- After fusing, upper and
lower redrive rollers envelope 13 along thepath 19 as the envelope moves through and out of the fuser roll nip. Thefunction generator 23 anddriver 24 continue pulsing the solenoid as theenvelope 13 is pulled along thepaper path 19 until the trailing end of theenvelope 13 exits the fuser nip. - When the
solenoid 21 is pulsed, the current to the solenoid from the solenoid driver is controlled to rise and fall in a profile to be described subsequently. The current profile minimizes the dynamics of the backup roll/solenoid system, to provide quiet operation of the system. The duration of the solenoid pulse is such that separation between thefuser roll 16 and thebackup roll 17 occurs for about 20 milliseconds. This provides time for the removal of the built-up stresses on theenvelope 13 and yet maintains all portions of the envelope in the fuser nip under pressure for a sufficient time to provide adequate fuse quality of the toner image on the envelope. - In one form of fuser, the
envelope 13 enters the fuser nip at a velocity of 51 mm/s (two inches per second). A pressure load of approximately 6.8 kg (15 pounds) between the silicon rubber backup roll and the rigid fuser roll creates a deformation in the backup roll of approximately 2.54 mm (0.100 inches). Therefore, a given section of the envelope is in the fuser nip for about 50 milliseconds. The set-point temperature for the fuser roll nip is about 180°C. This pressure, heat and time is sufficient to attain good fuse quality over a wide range of operating conditions. - As described earlier with regard to Figure 1, once the leading edge of the
envelope 13 reaches thepaper exit sensor 22, a signal is sent to functiongenerator 23 which triggers a voltage pulse. This voltage pulse is used as a reference forcurrent driver 24 which converts it to a current used to drive the linear push/pull solenoid 21. - With reference now to Figure 4, after the trigger signal is received, a time interval sufficient to allow the leading edge of the envelope to reach the redrive rollers (64,66 in Figure 2) is allowed to pass before the first solenoid pulse is initiated. This delay interval causes the first pulse to occur approximately 38 mm (1.5 inches) from the leading edge of the envelope. This distance is designated X0 in Figure 4. The number of pulses and spacing therebetween are controlled by the
function generator 23 in the illustrated form of the invention. A Wavetek 175 arbitrary waveform generator has been used for this purpose in one form of the invention. Advantageously, the function generator signals could be produced by the control software for the printer as part of the general printer control function. - In the present implementation, the pulses occur about one second apart, or each 51mm (two inches) along the envelope. This results in four pulses (as shown in Figure 4) for a number 10 (240mm (9 1/2 inch)) envelope, or three pulses for a number 7 3/4 (190mm (7 1/2 inch)) envelope. The length of the envelope can be automatically determined in the
pre-fuser portion 12 of theprinter 11 such as by measuring the time differential between making and breaking a paper sensor switch. This information can be used by thefunction generator 23 to determine the number of solenoid pulses required. - The current pulse produced by the
driver 24 tracks the voltage produced by thefunction generator 23, and takes the form shown in Figures 5 and 6. The current pulse to thesolenoid 21 results in a displacement of the backup roll as shown in Figure 6. The motion required to separate the rolls in the illustrated form of the invention is approximately 0.762mm (0.030 inches) . The time of separation for proper function can be as short as 5 milliseconds and as long as 20 milliseconds. Between these limits, the envelope has sufficient time to "relax" and the fuse grade is not significantly affected. In the present fuser arrangement, the heated fuser roll is a one millimeter thick aluminum tube having a 0.025mm (0.001 inch) thick coating of Teflon or Silverstone or the like. The backup roll is made up of a 10 millimeter diameter steel rod inside a 6 millimeter thick 25 dur SHORE A silicon rubber roll. - Thus it has been shown that in at least a preferred embodiment, the present invention provides a method of forming an image in an electrophotographic reproduction apparatus of the foregoing type in which creasing, folding, and treeing of envelopes is substantially reduced or eliminated.
Claims (9)
- A method of forming an image on a transfer medium (13) in an electrophotographic reproduction apparatus, comprising the steps of:developing a toned image and transferring that image to the said transfer medium;fusing the toned image to the transfer medium by advancing the transfer medium with the toned image thereon through a pressure nip (14);characterised by the pressure at the pressure nip being substantially reduced for one or more brief intervals as the toned image on the transfer medium advances through the pressure nip.
- A method as claimed in claim 1, wherein the position of the transfer medium (13) is detected as it begins to pass through the pressure nip (14) and a position signal is produced.
- A method as claimed in claim 2, wherein the pressure at the pressure nip (14) is substantially reduced in response to the position signal.
- A method as claimed in any preceding claim, wherein the pressure at the pressure nip (14) is substantially reduced for a brief interval of between 5 to 20 milliseconds.
- A method as claimed in any preceding claim, wherein the pressure at the pressure nip (14) is substantially reduced in a series of evenly spaced pulses.
- A method as claimed in claim 5, wherein there is a delay before the first pulse for the transfer medium (13) to advance far enough through the pressure nip (14) to reach a set of redrive rollers (64,66).
- A method as claimed in claim 6, wherein the first pulse occurs approximately 38 mm (1.5 inches) from the leading edge of the transfer medium (13).
- A method as claimed in claim 5, 6 or 7, wherein the pulses are spaced between 38 and 51 mm (1.5 and 2 inches) apart along the transfer medium (13).
- A method as claimed in claim 5, 6 or 7, wherein the pulses are spaced approximately one second apart.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US56558390A | 1990-08-10 | 1990-08-10 | |
US565583 | 1990-08-10 |
Publications (3)
Publication Number | Publication Date |
---|---|
EP0470860A2 EP0470860A2 (en) | 1992-02-12 |
EP0470860A3 EP0470860A3 (en) | 1992-07-22 |
EP0470860B1 true EP0470860B1 (en) | 1996-11-20 |
Family
ID=24259265
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP91307358A Expired - Lifetime EP0470860B1 (en) | 1990-08-10 | 1991-08-09 | Electrophotographic reproduction method having improved fuser |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0470860B1 (en) |
JP (1) | JP3219791B2 (en) |
BR (1) | BR9103425A (en) |
DE (1) | DE69123197T2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8346147B2 (en) | 2009-05-07 | 2013-01-01 | Fuji Xerox Co., Ltd. | Fixing unit and image forming apparatus |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110329823B (en) * | 2019-08-23 | 2020-08-14 | 杭州富阳新堰纸制品有限公司 | Wrinkle removing device for plastic film |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0413941A2 (en) * | 1989-08-25 | 1991-02-27 | International Business Machines Corporation | Method and apparatus for fusing envelopes |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4119831A (en) * | 1977-03-14 | 1978-10-10 | Rank Xerox, Ltd. | Contact pressure adjusting device in heating pressing fixing apparatus for electrophotographic copiers |
US4753543A (en) * | 1985-06-24 | 1988-06-28 | Ricoh Company, Ltd. | Electrostatic printing apparatus with heated adjustable pressure toner fixing rolls |
JPS6292979A (en) * | 1985-10-18 | 1987-04-28 | Mita Ind Co Ltd | Fixing device |
-
1991
- 1991-08-08 JP JP22329591A patent/JP3219791B2/en not_active Expired - Fee Related
- 1991-08-09 EP EP91307358A patent/EP0470860B1/en not_active Expired - Lifetime
- 1991-08-09 DE DE1991623197 patent/DE69123197T2/en not_active Expired - Fee Related
- 1991-08-09 BR BR9103425A patent/BR9103425A/en not_active IP Right Cessation
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0413941A2 (en) * | 1989-08-25 | 1991-02-27 | International Business Machines Corporation | Method and apparatus for fusing envelopes |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8346147B2 (en) | 2009-05-07 | 2013-01-01 | Fuji Xerox Co., Ltd. | Fixing unit and image forming apparatus |
Also Published As
Publication number | Publication date |
---|---|
EP0470860A3 (en) | 1992-07-22 |
DE69123197D1 (en) | 1997-01-02 |
DE69123197T2 (en) | 1997-04-17 |
JPH06342248A (en) | 1994-12-13 |
EP0470860A2 (en) | 1992-02-12 |
BR9103425A (en) | 1992-05-19 |
JP3219791B2 (en) | 2001-10-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0864942B1 (en) | Method for gloss control in an electrographic apparatus | |
US5268726A (en) | Electrophotographic reproduction apparatus having improved fuser to prevent wrinkling of envelopes using intermittent pressure | |
EP0513819B1 (en) | Electrostatically assisted transfer roller and method for directly transferring liquid toner to a print medium | |
US4676498A (en) | Sheet feeding apparatus | |
US6526239B2 (en) | Thermo-pressure fixing type printer | |
US6661989B2 (en) | Xerographic fusing apparatus with input sheet guide | |
JP2785547B2 (en) | Paper size detector | |
EP0704771A1 (en) | Device for conveying sheet members | |
EP0460303B1 (en) | Continuous-form electrophotographic printers | |
EP0470860B1 (en) | Electrophotographic reproduction method having improved fuser | |
EP0685775B1 (en) | Thermal transfer apparatus for fusing print dye on a media | |
US5895152A (en) | Fixing device and fixing temperature control method | |
EP0543405B1 (en) | Electrophotographic apparatus | |
US6633736B1 (en) | Automatically varying the transfer voltage in an electrophotographic development process based on the incoming path of the sheet of print media | |
JPH04274473A (en) | Fixing device and both-face image forming device | |
JPH10240062A (en) | Image forming device | |
JP7059719B2 (en) | Fixing device and image forming device | |
JP4143208B2 (en) | Sheet feeding apparatus and image forming apparatus provided with the apparatus | |
JP2003162175A (en) | Fixing device | |
JPH10222003A (en) | Image forming device | |
JPH0619362A (en) | Fixing device | |
JPH08211756A (en) | Post-transfer corrugator | |
JPS58160177A (en) | Controlling method for feeding paper | |
JPS6243314Y2 (en) | ||
GB2150885A (en) | Image forming apparatus with laminating mechanism |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): DE FR GB |
|
111Z | Information provided on other rights and legal means of execution |
Free format text: DE FR GB |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): DE FR GB |
|
17P | Request for examination filed |
Effective date: 19921007 |
|
17Q | First examination report despatched |
Effective date: 19940221 |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE FR GB |
|
REF | Corresponds to: |
Ref document number: 69123197 Country of ref document: DE Date of ref document: 19970102 |
|
ET | Fr: translation filed | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
REG | Reference to a national code |
Ref country code: GB Ref legal event code: IF02 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20080818 Year of fee payment: 18 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20080827 Year of fee payment: 18 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20080930 Year of fee payment: 18 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20090809 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST Effective date: 20100430 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090831 Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100302 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20090809 |