JP4403798B2 - Flash fixing device and image forming apparatus - Google Patents

Description

  The present invention relates to a flash fixing device that irradiates a paper on which a toner image is formed with flash light to fix the toner image on the paper, and forms a toner image on the paper based on the electrophotographic method, and then flashes the paper on the paper. The present invention relates to an image forming apparatus that fixes a toner image by irradiating light.

  In a printer using an electrophotographic system (hereinafter referred to as “electrophotographic printer”), an image (toner image) formed with powdered toner is transferred from an image carrier onto a recording medium such as recording paper, The toner image is fixed on the recording medium by applying heat energy (fixing energy) to the recording medium and melting the toner on the recording medium. 2. Description of the Related Art In recent years, electrophotographic printers capable of high-speed recording include a non-contact type that can heat a recording medium without directly contacting the recording medium as a fixing device for applying fixing energy to the image-transferred recording medium. A device using a fixing device has been developed. According to such a non-contact type fixing device, it is possible to apply sufficient fixing energy to the recording medium without affecting the conveyance speed of the recording medium. Suitable as a fixing device for printers. As such a non-contact type fixing device, for example, a flash fixing device that fixes a toner image on a recording medium by intermittently irradiating the recording medium with flash light is known.

  FIG. 9 shows an electrophotographic printer to which a conventional flash fixing is applied. The electrophotographic printer 100 is for recording an image on a continuous paper 102 in which perforations are formed at regular intervals on a long belt-like paper, and includes a photosensitive drum 104 as a toner image carrier. Yes. In the electrophotographic printer 100, a laser exposure unit 106, a developing unit 108, a transfer unit 110, a cleaning unit 112, and a charging unit 114 are arranged on the outer peripheral side of the photosensitive drum 104.

  Here, the laser exposure unit 106 exposes the photosensitive drum 104 with laser light modulated based on image information to form a latent image on the photosensitive drum 104, and the developing unit 108 forms on the photosensitive drum 104. A toner image is formed by attaching toner to the latent image formed. The feed roller 116 is linked to the formation of the toner image on the photosensitive drum 104, and feeds the continuous paper 102 drawn from the paper hopper 103 between the photosensitive drum 104 and the transfer unit 110. Transfers the toner image formed on the photosensitive drum 104 to the continuous paper 102 by electrostatic force. Thereafter, the cleaning unit 112 removes and collects the toner remaining on the photosensitive drum 104 to which the toner image has been transferred, and the charging unit 114 is prepared by the cleaning unit 112 to prepare for the next exposure by the laser exposure unit 106. The photosensitive drum 104 from which the toner has been removed is charged to a predetermined potential.

  On the other hand, the continuous paper 102 onto which the toner image has been transferred is conveyed to the flash fixing unit 118, and the flash fixing unit 118 emits flash light. As a result, the toner that has adhered to the continuous paper 102 to form a toner image is heated and melted, and the toner image is fixed on the continuous paper 102. At this time, in the electrophotographic printer 100, the control unit 122 operates the flash fixing unit 118 via the fixing driving unit 124 in response to an operation signal from the operation panel 120 or an instruction from a host device such as an external server or personal computer. To control. Specifically, the control unit 122 causes the flash lamp 126, which is a light source in the flash fixing unit 118, to emit light intermittently at predetermined time intervals in conjunction with the conveyance of the continuous paper 102, so The toner image is fixed for each area. Here, as the flash lamp 126, a xenon flash lamp formed in a substantially cylindrical shape is used.

  In the electrophotographic printer 100, the continuous paper 102 on which the toner image is fixed by the flash fixing unit 118 is transported from the flash fixing unit 118 to the swing guide 130 by a plurality of transport rollers 128, and is folded by the swing guide 130 from the perforation. While being accommodated in the stacker 132.

  FIG. 10 shows an emission spectrum distribution of a flash lamp as a light source in the flash fixing apparatus shown in FIG. 9 and an absorption spectrum distribution by toner and continuous paper (white paper). From FIG. 10, of the light emitted from the flash lamp 126, light of about 200 nm to 1100 nm has a higher contribution to fixing, that is, light in the infrared region has a higher contribution to fixing than the visible light region. I understand that.

  FIG. 11 shows a light emission energy distribution along the axial direction of a flash lamp which is a light source in the flash fixing apparatus shown in FIG.

  In general, the flash light emitted from the flash lamp 126 including a xenon flash lamp has a light emission energy distribution that is not uniform along the axial direction (arrow S direction) and the conveyance direction of the continuous paper 102 perpendicular to the axial direction. In order to make the irradiation amount of the flash light uniform in the transport direction, for example, as disclosed in Patent Document 1 and Japanese Patent Application Laid-Open No. 6-308852, a region where the emission energy distribution and the flash light are irradiated a plurality of times Various proposals have been made to optimize the range of (overstrike area) and prevent uneven fixing of the toner image.

Further, in order to make the flash light irradiation amount uniform in the transport direction, as shown in FIG. 11A, the flash lamp 126 has a dimension along the axial direction that is somewhat longer than the width of the continuous paper 102. The light intensity distribution along the axial direction of the flash light irradiated to the continuous paper 102 is obtained by irradiating the central side portion of the flash light whose emission energy distribution in the axial direction (paper width direction) is relatively flat. Is uniform.
Japanese Patent No. 2870705 JP-A-6-308852

  However, the flash lamp 126 has a characteristic that the emission energy distribution changes with time. In FIG. 11B, the solid line F1 shows the light emission energy distribution along the axial direction by the flash lamp 126 immediately after the start of use, and the broken line F2 shows the light emission along the axial direction by the flash lamp 126 after emitting 1 million times. The energy distribution is shown. As is clear from the comparison between the solid line F1 and the broken line F2, when the flash lamp 126 is used over a long period of time, a phenomenon occurs in which the light emission energy distribution decreases at both ends in the axial direction as compared to immediately after the start of use. For this reason, when the toner image on the continuous paper 102 is fixed using the flash lamp 126 in such a state, the amount of incident light on both end portions in the width direction of the continuous paper 102 is insufficient, and the toner image at both end portions is lost. There was a problem that the fixability deteriorated.

  Therefore, in order to prevent fixing deterioration of the toner image at both ends of the continuous paper 102, if the light emission amount of the flash lamp 126 is increased from the level of the broken line F2 to the level of the alternate long and short dash line F3, the central portion in the axial direction of the continuous paper 102 The amount of light entering the lens becomes excessive, and the toner is heated more than necessary in this portion. Thus, if the toner is heated more than necessary, the amount of smoke generated from the toner at the time of fixing increases, and the life of the deodorizing and deodorizing filter that removes and absorbs this smoke from the exhaust to the outside of the apparatus is shortened. Problems arise.

  In view of the above facts, the object of the present invention is to locally fix the toner image on the paper even if it becomes non-uniform along the axial direction of the light emission energy distribution by the flash lamp as the light emission time increases. It is an object of the present invention to provide a flash fixing device that can effectively improve deterioration and excessive heating, and an image forming apparatus that forms an image based on an electrophotographic system.

According to a first aspect of the present invention, a flash fixing device includes a tubular flash lamp that emits flash light, an opening that opens in a predetermined irradiation direction, and a reflective surface that surrounds the flash lamp. And a reflecting plate that reflects a part of flash light emitted from the flash lamp toward the opening by the reflecting surface, the flash light emitted from the flash lamp along the irradiation direction. In a flash lamp fixing device that irradiates a paper supported so as to face the opening and fixes the toner image transferred onto the paper, along the irradiation direction across the paper on which the toner image is formed. while being supported so as to be opposed to the opening, the anti-surface with respect to the flash light along the axial direction of the flash lamp And having a light correction member which allows adjusting the distribution rate.

In the flash fixing device according to the first aspect, the light correction member is supported so as to face the opening along the irradiation direction with the sheet on which the toner image is formed, and the axial direction of the flash lamp in the light correction member. Because the distribution of the reflectance of the flash light along the line can be changed, the flash lamp irradiates the paper, and a part of the flash light transmitted through the paper is reflected by the light correction member and re-enters the paper. In addition, if the distribution of the reflectance of the surface with respect to the flash light is appropriately adjusted, the light amount distribution along the axial direction of the flash light re-entering the paper from the light correction member can be adjusted to a desired distribution. Therefore, even if the emission energy distribution of the flash lamp decreases at both ends in the axial direction as the emission time increases, Supplemented by flash light reflected by the optical correction member under, can uniform the light intensity distribution along the axial direction of the flash light incident on the sheet.

  As a result, even if the light emission energy distribution of the flash lamp decreases with time at both ends in the axial direction, if the reflectance at the both ends in the axial direction of the light correction member is adjusted to increase with time, the width on the paper It is possible to improve the fixing failure of the toner image transferred to the vicinity of both ends in the direction, and to prevent the toner image (toner) transferred to the vicinity of the center in the width direction on the paper from being heated more than necessary.

  According to a second aspect of the present invention, there is provided the flash fixing device according to the first aspect, further comprising a cleaning unit that can clean the light reflecting surface that reflects the flash light in the light correction member at an arbitrary time. It is characterized by that.

  In the flash fixing device according to claim 2, the cleaning unit adheres to the light reflection surface of the light correction member by cleaning the light reflection surface of the light correction member that reflects the flash light at any time. If the light reflecting surface is cleaned by the cleaning means to remove the adhering material before the reflectivity with respect to the flash light is lowered by a predetermined value or more due to the adhering paper dust or fine toner adhering, the light correcting member It is possible to prevent the flash light reflected and re-incident on the paper from decreasing with time and the light amount distribution along the axial direction of the flash light incident on the paper from becoming non-uniform.

  The flash fixing device according to claim 3 is the flash fixing device according to claim 1 or 2, wherein a light emission counter that measures the light emission time of the flash lamp and a light emission time measured by the light emission time counter are preset. And a notification means for notifying the outside of the apparatus that the reflectance distribution along the axial direction of the light correction member needs to be changed.

  In the flash fixing device according to the third aspect, when the light emission time counted by the light emission time counter reaches a preset threshold value, the notifying unit has a reflectance of the light correction member along the axial direction. By notifying the outside of the apparatus that the distribution needs to be changed, if the threshold value is set according to the time at which fixing failure occurs due to the change in the emission energy distribution of the flash lamp, the emission energy of the flash lamp Before the fixing failure occurs due to the change in distribution, the operator can be informed that the fixing failure may occur due to the change in the light emission energy distribution of the flash lamp. Adjust the reflectance distribution along the direction to make the light quantity distribution along the axial direction of the flash light incident on the paper uniform. Kill as to become.

  According to a fourth aspect of the present invention, there is provided the flash fixing device according to the third aspect, wherein the reflectance distribution along the axial direction of the light correction member corresponding to the threshold value set in the informing means. Storage means for storing an appropriate pattern, and when the light emission time counted by the light emission time counter reaches a preset threshold value, the notification means is arranged along the axial direction of the light correction member. Notifying the outside of the apparatus that the reflectance distribution needs to be changed, and reading the appropriate pattern corresponding to the threshold value from the storage means and displaying it outside the apparatus.

  In the flash fixing device according to claim 4, when the notifying unit reaches a threshold value set in advance by the light emission time counter, a reflectance along the axial direction of the light correction member is reached. It is informed to the outside of the device that the distribution of the light source needs to be changed, and an appropriate pattern corresponding to the threshold value is read from the storage means and displayed outside the device, thereby fixing by the change in the emission energy distribution of the flash lamp. Before the defect occurs, the operator can appropriately adjust the reflectance distribution along the axial direction of the light correction member so that the light amount distribution along the axial direction of the flash light incident on the paper is made uniform. Become.

  According to a fifth aspect of the present invention, there is provided the flash fixing device according to any one of the first to fourth aspects, further comprising a light amount adjusting means capable of adjusting a light emission amount of the flash lamp at an arbitrary timing. It is characterized by.

  In the flash fixing device according to the fifth aspect, the light amount adjusting means can adjust the light emission amount of the flash lamp at an arbitrary timing, so that even when the light emission amount of the entire flash lamp decreases with time, the light amount adjusting means. As a result, the light emission amount of the flash lamp can be increased as appropriate, so that it is possible to prevent the occurrence of poor fixing due to a decrease in the light emission amount of the entire flash lamp over a long period of time.

  According to a sixth aspect of the present invention, there is provided an image forming apparatus for forming a toner image based on an electrophotographic system, an image forming means for transferring the toner image onto a sheet, and a toner image transferred by the image forming means. 7. An image forming apparatus comprising: a flash fixing device that irradiates a flashed paper with flash light to fix a toner image on the paper; and the flash fixing device according to any one of claims 1 to 6. A flash fixing device is used.

  In the image forming apparatus according to claim 6, by using the flash fixing device according to any one of claims 1 to 6 as the flash fixing device, the emission energy distribution of the flash lamp as the light emission time increases. Even when the both ends decrease in the axial direction, the decrease in the light emission energy can be compensated by the flash light reflected by the light correction member, so that the light quantity distribution along the axial direction of the flash light incident on the paper can be made uniform. Fixes poor fixing of the toner image transferred to the vicinity of both ends in the width direction on the paper, and prevents the toner image (toner) transferred to the vicinity of the center in the width direction on the paper from being heated more than necessary. it can.

  As described above, according to the flash fixing device and the image forming apparatus according to the present invention, the toner on the paper even if the light emission energy distribution by the flash lamp becomes non-uniform along the axial direction as the light emission time increases. It is possible to effectively improve the local fixing deterioration and excessive heating of the image.

  A flash fixing unit and an electrophotographic printer according to embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 shows an electrophotographic printer to which a flash fixing unit according to a first embodiment of the present invention is applied. The electrophotographic printer 10 is for recording an image on a continuous paper 12 in which perforations are formed at regular intervals on a long strip of paper, and includes a photosensitive drum 14 as a toner image carrier. Yes. In the electrophotographic printer 10, a laser exposure unit 16, a developing unit 18, a transfer unit 20, a cleaning unit 22, and a charging unit 24 are disposed on the outer peripheral side of the photosensitive drum 14.

  Here, the laser exposure unit 16 exposes the photosensitive drum 14 with the laser beam L modulated based on the image information to form a latent image on the photosensitive drum 14, and the developing unit 18 applies the photosensitive drum 14 to the photosensitive drum 14. A toner image is formed by attaching toner to the formed latent image. The feed roller 15 is linked to the formation of the toner image on the photosensitive drum 14, and feeds the continuous paper 12 between the photosensitive drum 14 and the transfer unit 20, and the transfer unit 20 is placed on the photosensitive drum 14. The formed toner image is transferred to the continuous paper 12 by electrostatic force. Thereafter, the cleaning unit 22 removes and collects the toner remaining on the photosensitive drum 14 to which the toner image is transferred, and the charging unit 24 is prepared by the cleaning unit 22 to prepare for the next exposure by the laser exposure unit 16. The photosensitive drum 14 from which the toner has been removed is charged to a predetermined potential.

  On the other hand, the continuous paper 12 onto which the toner image has been transferred is conveyed to the flash fixing unit 30, and the flash fixing unit 30 emits flash light. As a result, the toner that has adhered to the continuous paper 12 to form a toner image is heated and melted, and the toner image is fixed on the continuous paper 12. At this time, in the electrophotographic printer 10, the control unit 28 operates the flash fixing unit 30 via the fixing driving unit 26 in response to an operation signal from the operation panel 31 or an instruction from a host device such as an external server or personal computer. To control. Specifically, the control unit 28 causes the flash lamp 32 that is a light source in the flash fixing unit 30 to emit light intermittently at predetermined time intervals in conjunction with the conveyance of the continuous paper 12, so The toner image is fixed for each area. Here, as the flash lamp 32, a xenon flash lamp formed in a substantially cylindrical shape is used.

  In the electrophotographic printer 10, the continuous paper 12 on which the toner image is fixed by the flash fixing unit 30 is carried out from the flash fixing unit 30 to a swing guide (not shown) by a plurality of conveying rollers (not shown), and the sewing machine is used by the swing guide. The continuous paper 12 is accommodated in a stacker (not shown) while being folded starting from the eye.

  FIGS. 2A and 2B show the flash fixing unit shown in FIG. 1 as a cross-sectional view along the direction perpendicular to the axis and along the axial direction. Here, the axial direction is a direction along the central axis C of the flash lamp 32, and the direction perpendicular to the axis of the flash fixing unit 30 is a direction orthogonal to the axial direction. Further, it is assumed that the axial direction of the flash fixing unit 30 coincides with the width direction of the continuous paper 12.

  As shown in FIG. 2B, the flash fixing unit 30 is provided with a casing 34 formed in a casing shape opened downward as an outer portion thereof, and a flash lamp 32 is provided in the casing 34. And a reflector 36 is arranged. The reflector 36 is provided with an opening 38 that opens toward the continuous paper 12, and is provided with a reflecting surface 40 so as to surround the flash lamp 32. (Not shown) is fitted. As a result, part of the flash light emitted from the flash lamp 32 is reflected by the reflecting surface 40 and emitted from the opening 38 toward the continuous paper 12.

  A light correction member 42 is disposed in the flash fixing unit 30 so as to face the opening 38 of the reflector 36 with the continuous paper 12 interposed therebetween. The light correction member 42 is formed in a substantially rectangular plate shape whose longitudinal direction is the axial direction, and is supported so that the upper surface portion thereof is parallel to the continuous paper 12. Further, the light correction member 42 has a dimension along the axial direction longer than that of the flash lamp 32. The light correction member 42 has a base reflection surface 44 with a relatively high reflectivity on the upper surface portion of which is painted white, white clear, or the like. On the base reflection surface 44, an axial direction is provided. High reflecting plates 46 are disposed at both ends.

  As shown in FIG. 4A, the high reflection plate 46 is formed in a thin plate shape, and the upper surface portion facing the continuous paper 12 is a high reflection surface 48. The high reflection surface 48 is, for example, a smooth mirror surface with polished aluminum or silver plating, and has a reflectance of 75% or more in the infrared region of at least 1100 nm or less. The pair of high reflection plates 46 are supported on the base reflection surface 44 so as to be slidable along the axial direction, and the positions thereof are adjusted so as to face both ends of the continuous paper 12.

  3B shows the spectral energy distribution characteristics along the axial direction of the flash light emitted from the flash lamp 32, and FIG. 3C shows the axial direction (direction of arrow S) by the light correction member 42. The distribution characteristics of the reflectance with respect to the flash light along the line are shown. Here, in the light correction member 42, the reflectance of the base reflecting surface 44 is 60%, the reflectance of the high reflecting surface 48 is 90%, and the reflectance distribution pattern is the both ends of the continuous paper 12. The reflectivity is 90% in the area corresponding to each and 60% in the other areas.

  3B, a two-dot chain line G indicates the spectral energy distribution of the flash light incident on the continuous paper 12 when the light correcting member 42 is not provided in the flash fixing unit 30, and the solid line R indicates the flash fixing unit. 30 shows the spectral energy distribution of flash light incident on the continuous paper 12 when the light correction member 42 is provided at 30. As is apparent from the comparison between the two-dot chain line G and the solid line R, the light correction member 42 is provided in the flash fixing unit 30, so that the light correction member is provided in the vicinity of both ends of the continuous paper 12 facing the high reflection plate 46. Compared to the case where 42 is not provided, the spectral energy increases. This phenomenon is mainly caused by the flash lamp 32 irradiating the continuous paper 12, and part of the flash light transmitted through the continuous paper 12 is reflected by the high reflection surface 48 of the high reflection plate 46 and reenters the continuous paper 12. Caused by Further, another part of the flash light emitted from the flash lamp 32 and passing through the side of the continuous paper 12 is reflected by the high reflection surface 48 and is incident on both ends of the continuous paper 12. Contributing to the rise.

  4B and 4C show other configuration examples of the high reflection plate applicable to the flash fixing unit. In the high reflection plate 50 shown in FIG. 4B, a high reflection portion 54 having a high reflectance (90% or more) is formed on the high reflection surface 52 as a halftone dot pattern. This region is a low reflection portion 56 having a lower reflectance than the base reflection surface 44. In this way, by configuring the high reflection surface 52 by the high reflection portion 54 and the low reflection portion 56 of the halftone dot pattern, if the size and density of the halftone dots forming the high reflection portion 54 are adjusted, the high reflection plate 50 The reflectance of the highly reflective surface 52 can be adjusted over a wide range without changing the structure and material of itself.

  4C, similarly to the high reflection plate 50, a high reflection portion 60 having a high reflectance (90% or more) is formed as a halftone dot pattern on the high reflection surface 64 thereof. A region other than the high reflection portion 60 is a low reflection portion 62 having a lower reflectance than the base reflection surface 44. However, in the high reflection plate 58, the halftone dot size of the high reflection portion 60 is gradually reduced from the outside in the axial direction toward the inside. As a result, as shown in FIG. 4D, the reflectance of the high reflection plate 58 changes so as to decrease gradually from the outside in the axial direction toward the inside. By applying such a high reflection plate 58 to the flash fixing unit 30, the occurrence of a hump-like peak portion in the spectral energy distribution of the flash light incident on both ends of the continuous paper 12 shown in FIG. It is possible to obtain a flatter distribution energy distribution by suppressing effectively.

(Second Embodiment)
FIG. 5 shows a flash fixing unit according to the second embodiment of the present invention. The flash fixing unit 70 can be applied to the electrophotographic printer 10 shown in FIG. 1 instead of the flash fixing unit 30 according to the first embodiment. In the flash fixing unit 70 according to the second embodiment, the same parts as those of the flash fixing unit 30 according to the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  The flash fixing unit 70 is different from the flash fixing unit 30 in that a cleaning mechanism 72 for the light correction member 42 is provided. The cleaning mechanism 72 is provided with a cleaning brush 74. The cleaning brush 74 is provided with a block-shaped base portion 76, and a large number of fibrous brush hairs 78 having flexibility are implanted in the base portion 76. The cleaning brush 74 is disposed adjacent to the upper side of the light correction member 42 and is supported by the brush guide portion 80 so as to be movable along the axial direction.

  The brush guide unit 80 supports the cleaning brush 74 so as to be movable from one axially outer position (first standby position) of the light correction member 42 to the other axially outer position (second standby position). . Here, the cleaning brush 74 is provided with an operation lever 82 on the base portion 76, and the operation lever 82 projects from the inside of the casing 34 (see FIG. 2A) of the flash fixing portion 70 to the outside. Yes. The operator holds the operation lever 82 during cleaning of the light correction member 42 and applies an operation force along the axial direction to move the cleaning brush 74 along the axial direction from one standby position to the other standby position. It is possible. When the cleaning brush 74 moves from one standby position to the other standby position, the brush bristles 78 move while sliding on the high reflection surface 48 and the base reflection surface 44 of the light correction member 42. Foreign matter such as paper dust, toner dust and dust adhering to the high reflection surface 48 and the base reflection surface 44 is removed.

  In the flash fixing unit 70 according to the present embodiment, the cleaning brush 74 is operated by an operation force from an operator, but the cleaning mechanism 72 is provided with a brush drive unit that operates the cleaning brush 74 by a driving force such as a motor. When the cleaning signal is output from the control unit 28 to the flash fixing unit 70, the cleaning brush 74 may be automatically operated by the driving force from the brush driving unit.

  Further, in the electrophotographic printer 10 to which the flash fixing unit 70 according to the second embodiment is applied, as shown in FIG. 6, a print number counter 84 is additionally provided in the control unit 28. The print number counter 84 counts the number of unit pages (fixed number) divided by perforations in the continuous paper 12 fixed by the flash fixing unit 70, and temporarily stores the count value. The printed sheet counter 84 includes a memory unit 86, and the memory unit 86 stores a predetermined threshold value set in advance.

  Here, when the count value of the number of fixed sheets matches the threshold value stored in the memory unit 86, the printed sheet counter 84 outputs a message display signal corresponding to a predetermined cleaning message and resets the count value. This message display signal is output to an LCD display unit 88 provided on the operation panel 31 via an LCD (liquid crystal) drive unit (not shown) of the control unit 28, and the LCD display unit 88 that has received this message display signal receives the message display signal. A message prompting the operator to clean the light correction member 42 is displayed. As a result, the operator can be notified of the appropriate time before the reflectivity with respect to the flash light decreases by a predetermined value or more due to the adhering matter attached to the base reflecting surface 44 and the high reflecting surface 48 of the light correction member 42. If the operator who visually recognizes the cleaning mechanism 72 cleans the light reflecting surface and removes the adhering matter, the flash light reflected by the light correcting member 42 and re-entering the continuous paper 12 decreases with time. It is possible to prevent the light amount distribution along the axial direction of the flash light incident on the paper 12 from becoming non-uniform.

  If the cleaning mechanism 72 is provided with a brush driving unit that operates the cleaning brush 74 by a driving force such as a motor, the brush driving unit is activated in synchronization with the count-up of the print number counter 84, and a cleaning message is displayed. At the same time, the light correction member 42 may be automatically cleaned by the cleaning brush 74.

(Modified example of electrophotographic printer)
FIG. 7 shows a modification of the electrophotographic printer to which the flash fixing unit according to the embodiment of the present invention can be applied. In the electrophotographic printer 90 according to this modification, the control unit 92 is provided with a light emission number counter 94. The light emission number counter 94 counts the number of times the flash lamp 32 emits light in the flash fixing units 30 and 70, and temporarily stores this count value. The light emission counter 94 includes a memory unit 96. The memory unit 96 stores a predetermined threshold value set in advance, and the high reflection plate 46 in the light correction member 42 corresponding to the threshold value. An appropriate position along the axial direction is stored.

  Here, the light emission time of the flash lamp 32 is stable for a substantially constant time from the start of use until the end of its life, and the flash lamp 32 counts the number of times of light emission of the flash lamp 32 and uses the count value as a parameter. The 32 light emission times can be grasped almost accurately. In addition, the number of times of light emission counted by the light emission number counter 94 is reset and newly counted when the flash lamp 32 is replaced with a new one.

  In the electrophotographic printer 90, when the number of times of light emission of the light emission number counter 94 matches the threshold value stored in the memory unit 96, a message display signal corresponding to a predetermined light correction message is output and the threshold value from the memory unit 96 is output. The appropriate position of the high reflecting plate 46 corresponding to the value is read, and a position display signal corresponding to this appropriate signal is output. The message display signal and the position display signal are output to an LCD display unit 98 provided on the operation panel 31 via an LCD (liquid crystal) driving unit (not shown) of the control unit 92. The LCD display unit 98 that has received the message display signal and the position display signal displays a message to the operator that the position of the high reflector 46 needs to be adjusted along the axial direction, and responds to the threshold value. The appropriate position along the axial direction of the high reflection plate 46 is displayed.

  As shown in FIG. 8B, the appropriate position of the high reflection plate 46 is specifically the end portion on the inner side of the high reflection plate 46 along the axial direction immediately after the start of light emission of the flash lamp 32. Is set so that it slightly overlaps the outer edge of the continuous paper 12, and gradually moves inward in the axial direction as the number of light emission increases. If the spectral energy of the flash light of the flash lamp 32 is sufficiently uniform along the axial direction immediately after the start of use, the time immediately after the start of use is shown in FIG. As described above, the light correction member 42 may be used without attaching the high reflection plate 46.

  In the electrophotographic printer 90 shown in FIG. 7, when the light emission number of the flash lamp 32 counted by the light emission number counter 94 reaches a preset threshold value, the light emission number counter 94 moves in the axial direction of the light correction member 42. By informing the outside of the apparatus that the reflectance distribution along the line needs to be changed, the operator can change the emission energy distribution of the flash lamp 32 before fixing failure occurs due to the change of the emission energy distribution of the flash lamp 32. Therefore, before the fixing failure occurs, the operator adjusts the position of the high reflection plate 46 in the light correction member 42 and enters the continuous paper 12 before the fixing failure occurs. The light quantity distribution along the axial direction can be made uniform. At this time, since an appropriate position of the high reflection plate 46 corresponding to the threshold value is also displayed to the operator, the operator appropriately adjusts the position of the light correction member 42 along the axial direction of the high reflection plate 46. it can.

  In addition to the appropriate position of the high reflection plate, the memory unit 96 of the light emission number counter 94 stores the appropriate type of the high reflection plate to be used, and the high reflection plate shown in FIG. 4 as the high reflection plate. A message that prompts the operator to selectively attach any of the plates 46, 50, and 58 to the light correction member 42 may be displayed on the LCD display unit 98. The electrophotographic printers 10 and 90 described above form images on the continuous paper 12, but the flash according to the present invention is applied to an electrophotographic printer on a cut sheet having a certain size (for example, A4, B5, etc.). Needless to say, even when the fixing units 30 and 70 are applied, basically the same effects as those obtained when applied to the electrophotographic printers 10 and 90 can be obtained.

  The electrophotographic printers 10 and 90 described above are provided with a light amount adjusting unit (not shown) for adjusting the light emission amount of the flash lamp 32 of the flash fixing units 30 and 70 on the operation panel 31. When a predetermined operation is performed on the light amount adjustment unit, a light amount adjustment signal is output from the operation panel 31 to the control units 28 and 92. Upon receiving this light amount adjustment signal, the control units 28 and 29 control the flash light amount emitted from the flash lamp 32 via the fixing drive unit 26 so as to increase or decrease by the adjustment amount corresponding to the light amount adjustment signal. Thereby, in the electrophotographic printers 10 and 90 to which the flash fixing units 30 and 90 according to the present embodiment are applied, the light emission amount of the flash lamp 32 can be adjusted at an arbitrary timing. Even if it decreases, the light emission amount of the flash lamp 32 is increased as appropriate, and it is possible to prevent the occurrence of fixing failure due to a decrease in the light emission amount of the flash lamp 32 as a whole.

1 is a side view, partly in block diagram, illustrating the configuration of an electrophotographic printer according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view along the direction perpendicular to the axis and along the axial direction showing the configuration of the flash fixing unit shown in FIG. 1. 1A is a cross-sectional view showing the configuration of the flash lamp shown in FIG. 1, FIG. 1B is a graph showing spectral energy distribution characteristics along the axial direction of flash light emitted from the flash lamp, and FIG. It is a graph which shows the distribution characteristic of the reflectance with respect to the flash light along the axial direction by a member. (A)-(C) is a perspective view which shows the structural example of the high reflection board in a light correction member, (D) is a graph which shows distribution of the reflectance by the high reflection board shown by (C). FIG. 6 is a cross-sectional view along the direction perpendicular to the axis and along the axial direction showing a configuration of a flash fixing unit according to a second embodiment of the present invention. FIG. 6 is a block diagram illustrating a configuration example of a control unit in the electrophotographic printer to which the flash fixing unit illustrated in FIG. 5 is applied. FIG. 9 is a side view, partly in block diagram, illustrating a configuration of a modified example of an electrophotographic printer to which a flash fixing unit according to an embodiment of the present invention is applicable. It is a front view of the light correction member for demonstrating the appropriate position of the highly reflective board which changes with the light emission time of a flash lamp. It is a side view which shows the structure of the electrophotographic printer to which the conventional flash fixing was applied. 10 is a graph showing the distribution of the emission spectrum of a flash lamp and the distribution of the absorption spectrum of toner and continuous paper (white paper) in the flash fixing device shown in FIG. 9. 10 is a graph showing a light emission energy distribution along the axial direction of the flash lamp in the flash fixing device shown in FIG. 9.

Explanation of symbols

10 Electrophotographic printer (image forming device)
12 Continuous paper (paper)
14 Photosensitive drum 16 Laser exposure unit 26 Fixing drive unit 28 Control unit (light quantity adjusting means)
30 Flash fixing unit 31 Operation panel (light intensity adjustment means)
32 Flash lamp 36 Reflector 38 Opening 40 Reflecting surface 42 Light correction member 44 Base reflecting surface 46 High reflecting plate 48 High reflecting surface 50 High reflecting plate 58 High reflecting plate 70 Flash fixing unit 72 Cleaning mechanism (cleaning means)
74 Cleaning brush 90 Electrophotographic printer (image forming apparatus)
92 Control unit (notification means)
94 Light emission counter (light emission time counter)
96 memory section 98 LCD display section (informing means)

Claims (6)

A tubular flash lamp that emits flash light;
An opening that opens in a predetermined irradiation direction is provided, and a reflecting surface is provided so as to surround the flash lamp, and a part of flash light emitted from the flash lamp is directed to the opening by the reflecting surface. And a reflecting plate that reflects
In a flash lamp fixing device for irradiating a flash light emitted from the flash lamp onto a paper supported so as to face the opening along the irradiation direction and fixing a toner image transferred onto the paper,
A sheet on which a toner image is formed is supported so as to face the opening along the irradiation direction, and the surface reflectance distribution with respect to the flash light along the axial direction of the flash lamp is adjusted. A flash fixing device having a light correction member that enables the flash fixing device.   The flash fixing device according to claim 1, further comprising: a cleaning unit configured to clean a light reflection surface of the light correction member that reflects the flash light at an arbitrary time. A light emission time counter for measuring the light emission time of the flash lamp;
When the light emission time measured by the light emission time counter reaches a preset threshold value, the outside of the apparatus is notified that the reflectance distribution along the axial direction of the light correction member needs to be changed. Notification means;
The flash fixing device according to claim 1, further comprising: Storage means for storing an appropriate pattern of the reflectance distribution along the axial direction in the light correction member corresponding to the threshold set in the notification means,
When the light emission time counted by the light emission time counter reaches a preset threshold value, the notification means needs to change the reflectance distribution along the axial direction in the light correction member. 4. The flash fixing device according to claim 3, wherein the flash fixing device notifies the outside of the apparatus and reads the appropriate pattern corresponding to the threshold value from the storage means and displays it outside the apparatus.   5. The flash fixing device according to claim 1, further comprising: a light amount adjusting unit capable of adjusting a light emission amount of the flash lamp at an arbitrary timing. In addition to forming a toner image based on the electrophotographic method, an image forming unit for transferring the toner image onto a sheet, and a sheet on which the toner image is transferred by the image forming unit is irradiated with flash light on the sheet. An image forming apparatus having a flash fixing device for fixing a toner image,
Examples flash fixing device, an image forming apparatus characterized by using the flash fixing device of any one of claims 1 to 5.

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