JP2008015049A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of preventing throughput down when forming an image on a small size paper with inexpensive constitution, and also having high usability required when trouble is caused in the apparatus. <P>SOLUTION: When abnormality occurs in a moving means which moves a regulating member to regulate the aperture width of a ventilation port for cooling an image heating means in accordance with the width of recording material, whether or not succeeding image forming operation is performed is selected in accordance with the stopping position of the regulating member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine or a printer that forms an image on a recording material using an electrophotographic system. In particular, the present invention relates to an image forming apparatus provided with a so-called fixing device as image heating means for heating and fixing an unfixed image formed on a recording material.

  Conventionally, in an electrophotographic image forming apparatus, a method of forming a toner image on a recording material such as paper by a method called a Carlson process and fixing the toner image as a permanent image is generally used. Various fixing methods have been proposed for this purpose. From the viewpoint of fixing properties, a method of fixing a toner image by heating (thermal fixing method) is generally used. In particular, a method in which a toner image is directly brought into contact with a rotating body containing a heating source and fixed is widely used.

  In this heat fixing type fixing device, it is important to make the temperature distribution on the heating rotator such as a roller or a film uniform in the axial direction, including the region through which the recording material passes.

  That is, if there is a portion where the temperature is lower than the predetermined temperature, a fixing failure may occur. On the other hand, if it is too high, the rotating body and the proximity member may be thermally damaged.

  Furthermore, when the image non-sheet passing portion temperature is too high compared to the temperature of the sheet passing portion, the temperature of the end portion of the sheet passing portion is too high compared to the appropriate fixing temperature, so that the hot offset is reduced. There are concerns that arise.

  In recent years, for example, an image forming apparatus corresponding to various paper sizes from a relatively large size paper such as A3 size to a normally used small size paper such as A4R or B5 size as a recording material (copy paper). Is required. For this reason, it is necessary to configure the axial lengths of the heating rotary member and the pressure rotary member so as to correspond to a relatively large size such as an A3 size.

  However, in the case of adopting the above-described configuration, when a small size sheet such as A4R or B5 passes through the fixing device, it will be described with reference to FIG. The non-sheet passing area (b-2) through which the copy paper P does not pass increases in the fixing area (b-1). When the small-size copy paper is continuously copied, the surface of the heating rotary member 50 corresponding to the non-sheet passing area (b-2) is not deprived of heat by the copy paper. The surface temperature of -2) becomes very high.

  In order to solve the above-described temperature increase of the non-sheet passing portion, the following proposal has been made.

  In Conventional Example 1, the supply of heat to the heating rotary member 50 is stopped between the sheets so that the surface temperature of the heating rotary member 50 in the non-sheet passing area (b-2) is the same as the surface temperature of the sheet passing area. It corresponds by idling.

  Next, in Conventional Example 2, the amount of heat supplied to the non-sheet passing area (b-2) is less than the amount of heat supplied to the sheet passing area (b-3) for fixing small-size copy paper. As described above, a technique for changing the orientation ratio of a heating means such as a heater built in the heating rotating member 50 is employed.

  However, the above-described conventional example has the following problems.

  In the above conventional example 1, since it is necessary to perform idling rotation for cooling the heating rotating member 50 between sheets when continuously passing small-size paper, production when passing small-size copy paper P is performed. There arises a problem that the property becomes worse. In recent years, user demands for device productivity have gradually increased, and reducing the productivity at the time of size loading may not satisfy the product specifications required by the user.

  Next, when the configuration as in Conventional Example 2 is adopted, it is necessary to arrange heaters having a plurality of orientations in order to cope with a plurality of sizes, which may increase the cost.

  In order to prevent an increase in the surface temperature of the non-sheet passing area (b-2) when passing small-size paper, it has been proposed to cool the non-sheet passing area with cooling air.

  In the technique described in Patent Document 1, the periphery of the pressure roll in the fixing device is divided into a sheet passing area side and a non-sheet passing area side by a partition plate, and the non-sheet passing is performed from a cooling fan disposed inside the fixing apparatus. Cooling air is blown to the pressure roll outer peripheral member on the region side.

Further, in Patent Document 2, as described in Example 1, with reference to FIG. 16 attached to the present application, a cooling fan 104 is disposed above a top plate 105 that covers the fixing roll 101 and the pressure roll 102. Normally, air is blown to the upper side of the top plate 105 to prevent the temperature around the fixing unit from rising. When the paper passing through the fixing region is a small size paper, a window 106 as a guide device provided on the top plate 105 is opened. Cooling air is supplied to the surface portion of the fixing roll 101 that rotates through the non-sheet passing area.
JP-A-60-13679 JP-A-5-181382

  However, the proposal described above has the following problems.

  That is, in the conventional examples described in Patent Documents 1 and 2 in which the cooling air is blown to the heating rotating member, the cooling fan is provided inside the fixing device, so that it is necessary to use a cooling fan having high heat resistance, which increases the cost. There are concerns. In addition, a cooling fan with a relatively large air flow is required, and the fixing device itself becomes large. Even if a partition plate is provided, the cooling air flows from the non-sheet passing area side to the sheet passing area, the temperature decreases near the boundary between the sheet passing area and the non-sheet passing area, and the fixing temperature at the partition boundary portion decreases. Problem of fixing failure.

  As means for solving the above problems, the following configurations have been proposed.

  That is, in order to cool the non-sheet passing area passing surface which is the surface portion of the heating rotating member that passes through the non-sheet passing area, a blower opening is formed facing the non-sheet passing area passing surface of the heating rotating member. A non-sheet passing area cooling duct and a cooling device having a blower fan for blowing cooling air to the non-sheet passing area cooling duct, and in the non-sheet passing area according to the width of the small size paper. The fixing device includes a shielding plate that adjusts an area where the cooling air is blown to an optimum width, and further includes an opening width adjusting member that adjusts the opening width by the shielding plate according to the width of the small size paper.

  In addition, the cooling fan that blows the cooling air has a control unit that is turned ON / OFF at a predetermined timing using the temperature detection result of the non-sheet passing region. Further, the shielding plate that adjusts the area for blowing the cooling air to the optimum opening width according to the width of the small size paper shields the heating rotator and the cooling fan, so that the temperature of the cooling fan unit does not increase. Without using a cooling fan with high heat resistance, it is possible to provide a fixing device that can be efficiently prevented at low cost / space-saving and has excellent safety.

  However, the above proposal has the following problems.

  In other words, in the above configuration, an inexpensive fan with low heat resistance is used as the cooling fan in order to reduce the cost of the apparatus. However, when such a low heat-resistant fan is used and the shield plate cannot be moved due to a failure of the shield plate moving means, the image forming apparatus operates in order to prevent a failure due to a temperature rise of the cooling fan. It becomes impossible to do. Regardless of whether a decisive problem occurs in the output image, it is not desirable from the viewpoint of usability to prohibit the operation of the apparatus while normal image formation is possible. It is desirable from the viewpoint of usability that the operation of the apparatus can be continued by degrading the function at least from the notification of the occurrence of the failure until the service person repairs the device.

  Therefore, an object of the present invention is to provide an apparatus as much as possible when a failure occurs in the mechanism of the air cooling means or the air flow restricting member for cooling the edge that can solve the problem of temperature rise at the edge when passing a small size paper. An object of the present invention is to provide an image forming apparatus that can operate without stopping.

  Another object of the present invention is to provide an image forming apparatus that can prevent a reduction in throughput when an image is formed on a small-size sheet with an inexpensive configuration and that has high usability when a failure occurs in the apparatus. Is to provide.

The above object is achieved by the image forming apparatus according to the present invention. In summary, according to the first aspect of the present invention, the image forming means for forming an image on the recording material, the image heating means for heating the image on the recording material, and the air outlet for cooling the image heating means. An image forming apparatus comprising: a blowing unit that blows air toward the surface; a regulating member that regulates an opening width of the blowing port according to a width of the recording material; and a moving unit that moves the regulating member.
An image forming apparatus is provided that includes selection means for selecting whether or not to perform a subsequent image forming operation according to the stop position of the restricting member when an abnormality occurs in the moving means.

According to the second aspect of the present invention, the image forming means for forming an image on the recording material, the image heating means for heating the image on the recording material, and the air blowing toward the air blowing port for cooling the image heating means. An image forming apparatus comprising: a blowing unit that regulates; a regulating member that regulates an opening width of the blowing port according to a width of a recording material; and a moving unit that moves the regulating member.
An image forming apparatus capable of selecting a mode for operating the blowing unit when a subsequent image forming operation is executed in a state where at least a part of the blowing port is opened due to an abnormality of the moving unit. Is provided.

  According to the image forming apparatus of the present invention, when a failure occurs in the air cooling means or the air flow restricting member for cooling the edge to solve the problem of the temperature rise at the edge when passing a small size, as much as possible. It can operate without shutting down the device. As a result, it is possible to prevent a reduction in throughput when an image is formed on a small size paper with an inexpensive configuration, and usability is high when an apparatus failure occurs.

  The image forming apparatus according to the present invention will be described below in more detail with reference to the drawings.

Example 1
FIG. 1 shows a schematic cross section of an electrophotographic full color printer which is an embodiment of an image forming apparatus according to the present invention.

  In this embodiment, the image forming apparatus includes four image forming units (image forming units) 1 (1Y, 1M, 1C, 1Bk). That is, an image forming unit 1Y that forms a yellow image, an image forming unit 1M that forms a magenta image, an image forming unit 1C that forms a cyan image, and an image formation that forms a black image. Part 1Bk. These four image forming units 1Y, 1M, 1C, and 1Bk are arranged in a line at regular intervals.

  Each of the image forming units 1Y, 1M, 1C, and 1Bk has an image forming unit that forms an image on a recording material. That is, the image forming means in each of the image forming units 1Y, 1M, 1C, and 1Bk is a drum type electrophotographic photosensitive member (hereinafter referred to as “photosensitive drum”) 2 (2a, 2b, 2c, and so on) as an image carrier. 2d). Further, around each of the photosensitive drums 2a, 2b, 2c, and 2d, a primary charger 3 (3a, 3b, 3c, and 3d) and a developing device 4 (4a, 4b, 4c, and 4d) constituting an image forming unit. The transfer roller 5 (5a, 5b, 5c, 5d) and the drum cleaner device 6 (6a, 6b, 6c, 6d) are respectively disposed. A laser exposure device 7 is installed below the primary chargers 3a, 3b, 3c, and 3d and the developing devices 4a, 4b, 4c, and 4d.

  Each developing device 4a, 4b, 4c, and 4d contains yellow toner, magenta toner, cyan toner, and black toner, respectively.

  Each of the photosensitive drums 2a, 2b, 2c, and 2d is a negatively charged OPC photosensitive member having a photoconductive layer on an aluminum drum base, and is driven in a direction indicated by an arrow (clockwise in FIG. 1) by a driving device (not shown). Direction) at a predetermined process speed.

  The primary chargers 3a, 3b, 3c, and 3d as primary charging means bring the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d to a predetermined negative potential by a charging bias applied from a charging bias power source (not shown). Charge uniformly.

  The developing devices 4a, 4b, 4c, and 4d as developing means contain toner, and attach toner of each color to the electrostatic latent images formed on the photosensitive drums 2a, 2b, 2c, and 2d, respectively. Develop (visualize) as an image.

  Transfer rollers 5a, 5b, 5c, and 5d as primary transfer units respectively contact the photosensitive drums 2a, 2b, 2c, and 2d via the intermediate transfer belt 8 in the primary transfer portions 32a, 32b, 32c, and 32d, respectively. It is arranged so that it can touch.

  The drum cleaners 6a, 6b, 6c, and 6d as drum cleaning means respectively transfer residual toner remaining at the time of primary transfer on the photosensitive drums 2a, 2b, 2c, and 2d to the photosensitive drums 2a, 2b, 2c, and 2d. A cleaning blade or the like for removal from the surface.

  The intermediate transfer belt 8 is disposed on the upper surface side of each of the photosensitive drums 2a, 2b, 2c, and 2d, and is stretched between the secondary transfer counter roller 10 and the tension roller 11. Further, the secondary transfer counter roller 10 is disposed in the secondary transfer portion 34 so as to be in contact with the secondary transfer roller 12 via the intermediate transfer belt 8. The intermediate transfer belt 8 is made of a dielectric resin such as polycarbonate, polyethylene terephthalate resin film, polyvinylidene fluoride resin film, or the like.

  In addition, the intermediate transfer belt 8 has a primary transfer surface 8a formed on the surface facing the photosensitive drums 2a, 2b, 2c, and 2d, inclined with the secondary transfer roller 12 side facing downward.

  That is, the intermediate transfer belt 8 is disposed on the upper surface of the photosensitive drums 2a, 2b, 2c, and 2d so as to be movable, and has a primary transfer surface, that is, a lower flat surface 8a formed on the surface facing the photosensitive drum 2. The secondary transfer unit 34 is inclined so that the side is the lower side. Specifically, this inclination angle is set to about 15 °. Further, as described above, the intermediate transfer belt 8 is disposed on the secondary transfer portion 34 side, and the secondary transfer counter roller 10 that applies a driving force to the intermediate transfer belt 8, and the primary transfer portions 32a, 32b, and 32c. , 32d and the tension roller 11 which is disposed on the opposite side and applies tension to the intermediate transfer belt 8, and is stretched by two.

  The secondary transfer counter roller 10 is disposed so as to be in contact with the secondary transfer roller 12 via the intermediate transfer belt 8 at the secondary transfer unit 34. Further, a belt cleaning device 13 for removing and collecting the transfer residual toner remaining on the surface of the intermediate transfer belt 8 is installed outside the endless intermediate transfer belt 8 and in the vicinity of the tension roller 11.

  In addition, a fixing device 100 as an image heating unit that heats and fixes an image formed on the recording material P is installed downstream of the secondary transfer unit 34 in the conveyance direction of the recording material P. As the fixing device 100, a heat fixing device having an arbitrary configuration can be used. In this embodiment, as will be described in detail later, the fixing device 100 is an on-demand fixing device of a film heating method and a pressurizing rotating body driving method (tensionless type), and includes a first fixing member 50 and a second fixing member 60. Are provided in a vertical path configuration.

  The exposure device 7 includes laser light emitting means for emitting light corresponding to a time-series electric digital pixel signal of given image information, a polygon lens, a reflection mirror, and the like. The exposure device 7 exposes the photosensitive drums 2a, 2b, 2c, and 2d to the surfaces of the photosensitive drums 2a, 2b, 2c, and 2d charged by the primary chargers 3a, 3b, 3c, and 3d. An electrostatic latent image of each color corresponding to the image information is formed.

  Next, an image forming operation by the image forming apparatus having the above configuration will be described.

  When an image formation start signal is issued, the photosensitive drums 2a, 2b, 2c, and 2d of the image forming units 1Y, 1M, 1C, and 1Bk that are rotationally driven at a predetermined process speed are respectively connected to the primary chargers 3a, 3b, 3c and 3d are uniformly negatively charged. Then, the exposure device 7 irradiates a color light-separated image signal inputted from the outside from the laser light emitting element, and passes each color on each photosensitive drum 2a, 2b, 2c, 2d via a polygon lens, a reflection mirror, and the like. An electrostatic latent image is formed.

  First, in the image forming unit 1Y, yellow is developed by the developing device 4a in which a developing bias having the same polarity as the charging polarity (negative polarity) of the photosensitive drum 2a is applied to the electrostatic latent image formed on the photosensitive drum 2a. The toner is attached to make a visible image as a toner image. This yellow toner image is driven by a transfer roller 5a to which a primary transfer bias (a reverse polarity (positive polarity) to toner) is applied in a primary transfer portion 32a between the photosensitive drum 2a and the transfer roller 5a. Primary transfer is performed on the intermediate transfer belt 8.

  The intermediate transfer belt 8 onto which the yellow toner image has been transferred is moved to the image forming unit 1M side. Also in the image forming unit 1M, the magenta toner image formed on the photosensitive drum 2b is superimposed on the yellow toner image on the intermediate transfer belt 8 in the same manner as described above, and the primary transfer unit 32b. Transcribed.

  At this time, the transfer residual toner remaining on the photosensitive drums 2a and 2b is scraped off and collected by a cleaner blade or the like provided in the drum cleaner devices 6a and 6b.

  In the same manner, cyan and black toner images formed by the photosensitive drums 2c and 2d of the image forming units 1C and 1Bk on the yellow and magenta toner images superimposed and transferred on the intermediate transfer belt 8 are respectively primary transferred. A full-color toner image is formed on the intermediate transfer belt 8 by sequentially superposing the portions 32c and 32d. Transfer residual toner remaining on the photosensitive drums 2c and 2d is scraped off and collected by a cleaner blade or the like provided in the drum cleaner devices 6c and 6d.

  On the other hand, transfer paper (paper) P as a recording material selected from the paper feed cassette 17 or the manual feed tray 20 and fed through the transport path 18 is fed.

  The transfer paper P is transferred by the registration roller 19 in accordance with the timing at which the front end of the full color toner image on the intermediate transfer belt 8 is moved to the secondary transfer portion 34 between the secondary transfer counter roller 10 and the secondary transfer roller 12. It is conveyed to the next transfer unit 34. Full-color toner images are collectively transferred to the transfer paper P conveyed to the secondary transfer section 34 by the secondary transfer roller 12 to which a secondary transfer bias (polarity opposite to the toner (positive polarity)) is applied. Is done.

  The transfer paper P on which the full-color toner image is formed is conveyed to the fixing device 100, and the full-color toner image is heated and pressurized at the fixing nip N between the first fixing member 50 and the second fixing member 60. Then, it is heat-fixed on the surface of the transfer paper P. Thereafter, the transfer paper P is discharged onto the paper discharge tray 22 on the upper surface of the main body by the paper discharge roller 21, and a series of image forming operations is completed.

  The secondary transfer residual toner and the like remaining on the intermediate transfer belt 8 are removed and collected by the belt cleaning device 13.

  The above is the image forming operation at the time of single-sided image formation.

  Next, a double-sided image forming operation in the image forming apparatus in this embodiment will be described.

  The operation up to the point where the image is conveyed to the fixing device 100 is the same as the one-sided image forming operation.

  That is, the full-color toner image is heated and pressurized at the fixing nip portion between the first fixing member 50 and the second fixing member 60 and thermally fixed on the surface of the transfer paper P. Thereafter, the rotation of the paper discharge roller 21 is stopped in a state where most of the transfer paper P is discharged onto the paper discharge tray 22 on the upper surface of the main body by the paper discharge roller 21. At that time, the transfer paper P is stopped so that the rear end position of the transfer paper P reaches the reversible position 42.

  Subsequently, in order to feed the transfer paper P, which has been transported by stopping the rotation of the paper discharge roller 21, to the double-sided path including the double-sided rollers 40, 41, the paper discharge roller 21 rotates in the reverse direction to the normal rotation. Let By rotating the paper discharge roller 21 in the reverse direction, the rear end side of the transfer paper P located at the reversal position 42 is set as the front end side and reaches the double-sided roller 40.

  Thereafter, the transfer paper P is conveyed to the double-sided roller 41 by the double-sided roller 40, and the transfer paper P is sequentially conveyed toward the registration roller 19 by the double-sided rollers 40 and 41. In the meantime, an image formation start signal is generated, and the front end of the full-color toner image on the intermediate transfer belt 8 is moved between the secondary transfer counter roller 10 and the secondary transfer roller 12 as in the case of the above-described single-side image formation. The transfer paper P is moved to the secondary transfer portion 34 by the registration roller 19 in accordance with the timing of the movement.

  In the secondary transfer unit 34, the front end of the toner image and the front end of the transfer material P are made to coincide with each other, and the toner image is transferred. After that, as in the single-sided image forming operation, the image on the transfer material P is fixed by the fixing device 100, conveyed again by the paper discharge roller 21, and finally discharged onto the paper discharge tray 22, where a series of The image forming operation ends.

  FIG. 2 is a control block diagram in the image forming apparatus. A control means (CPU) 171 for performing basic control of the image forming apparatus is connected to a ROM 174 in which a control program is written, a work RAM 175 for performing processing, and an input / output port 173 by an address bus and a data bus. The input / output port 173 is connected to various loads such as a motor and a clutch for controlling the image forming apparatus and inputs such as a sensor for detecting the position of the paper. In the present exemplary embodiment, as will be described in detail later, the control unit 171 controls various operations related to the fixing device 100 as well as the image forming operation.

  The CPU 171 sequentially performs input / output control via the input / output port 173 in accordance with the contents of the ROM 174 to execute an image forming operation. An operation unit 172 is connected to the CPU 171 and controls display means and key input means of the operation unit 172. The operator instructs the CPU 171 to switch the image forming operation mode and display via the key input means, and the CPU 171 displays the state of the image forming apparatus 100 and the operation mode setting by key input. The CPU 171 includes an external I / F processing unit 400 that transmits and receives image data and processing data from an external device such as a PC, an image memory unit 300 that performs image expansion processing and temporary storage processing, and an image memory unit 300. Connected to the image forming unit 1 is a process for exposing the transferred line image data to the exposure device 7.

  Next, the details of the image memory unit 300 will be described with reference to FIG.

  In the image memory unit 300, image data received from the external I / F processing unit 400 via the memory controller unit 302 is written into a page memory 301 constituted by a memory such as a DRAM, and image reading to the image forming unit 1 is performed. Access image input / output.

  The memory controller unit 302 determines whether the image data from the external device received from the external I / F processing unit 400 is compressed data. If it is determined that the image data is compressed data, the compressed data expansion processing unit After performing the decompression process using 303, a write process is performed on the page memory 301 via the memory controller unit 302.

  The memory controller unit 302 generates a DRAM refresh signal of the page memory 301 and arbitrates access to the page memory 301 for writing from the image I / F processing unit 400 and reading to the image forming unit 1. Further, in accordance with an instruction from the CPU 171, the write address to the page memory 301, the read address from the page memory 301, and the read direction are controlled.

  The configuration of the external I / F processing unit 400 will be described with reference to FIG.

  The external I / F processing unit 400 receives image data and print command data transmitted from the external device 500 via any of the USB I / F unit 401, the Centro I / F unit 402, and the network I / F unit 403. In addition, the status information of the image forming apparatus determined by the CPU 171 is transmitted to the external apparatus 500. Here, the external device 500 is a computer, a workstation, or the like.

  Print command data received from the external device 500 via any of the USB I / F unit 401, the Centro I / F unit 402, and the network I / F unit 403 is processed by the CPU 171 and the print operation is performed by the image forming unit 1 or Using the I / O 173 in FIG. 2, settings and timing for executing the print operation are generated.

  Image data received from the external device 500 via any of the USB I / F unit 401, the Centro I / F unit 402, and the network I / F unit 403 is transferred to the image memory unit 300 according to the timing based on the print command data. The image is transmitted and processed by the image forming unit 1 to form an image.

  FIG. 5A is a schematic cross-sectional view of the fixing device 100 in this embodiment. The fixing device 100 of this embodiment is a film heating method using a cylindrical film as a film-like fixing member disclosed in Japanese Patent Application Laid-Open Nos. 4-44075 to 44083, Japanese Patent Application Laid-Open No. 4-204980 to 204984, and the like. This is an on-demand fixing device of a rotating body driving system for pressure (tensionless type).

  The fixing device 100 of this embodiment includes a film assembly 50 as a first fixing member and an elastic pressure roller 60 as a second fixing member. Is formed.

  The film assembly 50 includes a heat-resistant and rigid film guide member (stay: inner surface backup member of a film-like fixing member) 51 having a substantially semicircular arc shape in cross section, and a lower surface of the film guide member 51. A ceramic heater 52 serving as a heating means (heating body) disposed in a recessed groove portion provided along the longitudinal length of the film and a film guide member 51 to which the heater 52 is attached and loosely fitted. It comprises an endless belt-like (cylindrical) heat-resistant fixing film 53 as a film-like fixing member, a pressurizing rigid stay 54 inserted into the film guide member 51, and the like.

  The pressure roller 60 is formed by providing an elastic layer 60b such as silicone rubber on the cored bar 60a to reduce the hardness. In order to improve the surface property, a fluororesin layer 60c made of PTFE, PFA, FEP or the like is further provided on the outer periphery. May be provided. The pressure roller 60 is arranged such that both ends of the cored bar 60a are rotatably supported by bearings between the front and back side plates of the apparatus chassis (not shown) via a bearing member.

  The film assembly 50 is disposed on the upper side of the pressure roller 60 and parallel to the pressure roller 60 with the ceramic heater 52 facing downward, and the pressure rigid stay 54 is attached to the pressure roller 60 by a biasing spring (not shown). Press and urge in the axial direction. As a result, the downward surface of the ceramic heater 52 is pressed against the elastic layer 60b of the pressure roller 60 through the fixing film 53 against the elasticity of the elastic layer 60b, and a fixing nip portion N having a predetermined width required for heat fixing. Is formed.

  The pressure roller 60 is rotationally driven in a counterclockwise direction indicated by an arrow by a driving motor M as a driving unit. A rotational force acts on the fixing film 53 by the frictional force at the fixing nip N between the pressure roller 60 and the outer surface of the fixing film 53 by the rotational driving of the pressure roller 60. As a result, the fixing film 53 has a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 60 in the clockwise direction indicated by the arrow while the inner surface of the fixing film 53 slides in close contact with the lower surface of the ceramic heater 52 in the fixing nip N. The outer periphery of the film guide member 51 is rotated (pressure roller driving method). In order to reduce the mutual sliding frictional force between the lower surface of the ceramic heater 52 and the inner surface of the fixing film 11 in the fixing nip portion N, a lubricating member 54 is disposed on the lower surface of the ceramic heater 52 in the fixing nip portion N. A lubricant such as heat-resistant grease is interposed between the inner surface and the inner surface.

  Then, the rotation of the pressure roller 60 is started based on the print start signal, and the heating up of the ceramic heater 52 is started. Heating up of the ceramic heater 52 is performed by supplying power from an unillustrated power source to the energized heat generating layer 52b (FIG. 5C) of the ceramic heater 52, so that the energized heat generating layer 52b generates heat and the ceramic heater 52 quickly rises in temperature. . The CPU 171 makes the heater temperature detected by the temperature sensors 55 and 56 (FIG. 5A, FIG. 6) such as thermistors provided at the center and the end in contact with the heater 52 be a predetermined substantially constant temperature (fixing temperature). ) To control the energization of the energized heat generating layer 52b. That is, the ceramic heater 52 is heated and adjusted to a predetermined fixing temperature.

  Due to the rotation of the pressure roller 60, the rotational peripheral speed of the fixing film 53 becomes steady, and the temperature of the ceramic heater 52 rises to a predetermined level. In this state, the transfer paper P carrying the toner image t as the material to be heated is introduced between the fixing film 53 and the pressure roller 60 in the fixing nip N with the toner image carrying surface side set to the fixing film 53 side. Is done. As a result, the transfer paper P is brought into close contact with the lower surface of the ceramic heater 52 via the fixing film 53 in the fixing nip portion N and moves and passes through the fixing nip portion N together with the fixing film 53. In the moving and passing process, the heat of the ceramic heater 52 is applied to the transfer paper P through the fixing film 53, and the toner image t is heated and fixed on the surface of the transfer paper P. The transfer paper P that has passed through the fixing nip N is separated from the surface of the fixing film 53 and conveyed.

  The fixing film 53 includes a base layer 53a, an elastic layer 53b, and a release layer 53c, as shown in the schematic diagram of the layer structure of FIG. The base layer 53a has a film thickness of 100 μm or less, preferably 50 μm or less and 20 μm or more in heat-resistant polyimide, polyimide amide, PEEK, PES, PPS, PTFE, PFA, in order to reduce heat capacity and improve quick start properties. A film such as FEP can be used. In this example, a cylindrical polyimide film having a diameter of 25 mm was used.

The elastic layer 53b has a rubber hardness of 10 degrees (JIS-A), a thermal conductivity of 4.18605 × 10 ⁻¹ W / m · ° C. (1 × 10 ⁻³ [cal / cm.sec.deg]), and a thickness of 200 μm. Silicone rubber was used. As the release layer 53c, a PFA coating layer having a thickness of 20 μm was used.

  As the release layer 53c, a PFA coating layer having a thickness of 20 μm was used. A PFA tube may be used. The PFA coat is excellent in that the thickness can be reduced and the effect of enveloping the toner is larger than the PFA tube in terms of material. On the other hand, since the mechanical and electrical strength of the PFA tube is superior to that of the PFA coat, it can be used properly depending on the case.

  The ceramic heater 52 as a heating body in this embodiment is a back surface heating type using aluminum nitride or the like as a heater substrate, and has a low length with a direction perpendicular to the moving direction of the fixing film 53 and the transfer paper P as a longitudinal direction. This is a horizontally long linear heating element with a heat capacity.

  FIG. 5C is a schematic cross-sectional view of the ceramic heater 52. On the heater substrate 52a made of aluminum nitride and the like, and on the back surface side of the heater substrate 52a (on the surface opposite to the fixing film facing surface side). A heating layer 52b provided along the length, for example, by applying an electric resistance material such as Ag / Pd (silver / palladium) to a width of about 10 μm and a width of 1 to 5 mm by screen printing, and the like. The protective layer 52c made of glass or fluororesin is provided as a basic configuration. In this embodiment, a sliding member (lubricating member) 54 is provided on the front surface side (fixing film facing surface side) of the heater substrate 52a.

  By energizing between both ends of the heat generating layer 52b of the ceramic heater 52, the heat generating layer 52b generates heat, and the heater 52 rapidly rises in temperature. The CPU 171 supplies power to the heater so that the heater temperature is detected by temperature sensors 55 and 56 for detecting the central and end portions arranged in contact with the outer surface of the heater protective layer 52c. The heater 52 is controlled in temperature by controlling energization to the heat generating layer 52b (not shown).

  The ceramic heater 52 is fixedly supported by being fitted in a groove formed along the length of the guide at the substantially central portion of the lower surface of the film guide 51 by exposing the heater substrate surface provided with the lubricating member 54 downward. It is. In the fixing nip portion N, the surface of the lubricating member 54 of the ceramic heater 52 and the inner surface of the fixing film 53 slide in contact with each other.

  Next, the cooling mechanism of the fixing device 100 of this embodiment will be described.

  When the transfer sheet P having a size smaller than the maximum sheet passing size passes in the axial direction of the fixing device 100 illustrated in FIG. 5A, the transfer paper P is not in accordance with the temperature detected by the edge detection temperature sensor 56. The surface portion of the non-sheet passing area, which is the surface portion of the fixing film 53 that passes through the sheet passing area, is cooled. For this purpose, as shown in FIGS. 5A and 6, cooling devices 70 (70 a and 70 b) are arranged so as to face the non-sheet passing area passing surface of the fixing film 53. Each of the cooling devices 70a and 70b has the same configuration, a non-sheet passing area cooling duct 71 in which an air blowing opening 72 is formed, a blower fan 73 for blowing cooling air to the non-sheet passing area cooling duct 71, and the like. It has the ventilation means comprised by these. The blower fan 73 is driven with a predetermined load by a drive motor Mf (FIG. 5A) as a drive source.

  Further, according to this embodiment, as shown in FIGS. 5A and 6 to 9, the air blowing from the air blowing opening 72 to the fixing device 100 is shielded adjacent to the cooling device 70 (70 a, 70 b). A ventilation shielding device 80 is disposed.

  The air blocking device 80 includes a substrate 81 that covers the outer periphery of the fixing film 53 of the fixing device 100 and is disposed between the outer surface of the fixing film 53 and the air blowing opening 72 of the cooling device 70.

  On the substrate 81, at positions corresponding to the air blowing openings 72 of the respective cooling devices 70a and 70b, that is, in the vicinity of both ends in the longitudinal direction of the fixing device 100 (direction perpendicular to the moving direction of the transfer paper P), Blower ports 82 (82a, 82b) are formed.

  Further, the substrate 81 has a regulating member 83 (83a, 83a) that regulates the opening width of each opening 82 (82a, 82b) and can restrict the blowing from the opening 82 (82a, 82b) to the fixing film 53. 83b) and restricting member driving means 84 as moving means for moving the restricting members 83 (83a, 83b) are provided.

  In this embodiment, the restricting member driving means 84 functions as an opening adjusting means, and includes a pinion gear 85 attached to the substrate 81, and can be driven by a driving motor Mo (FIG. 6). The drive motor Mo is driven and controlled by the control means 171.

  On the other hand, the restricting member 83 (83a, 83b) includes a shield plate 86 (86a, 86b) disposed so as to cover the openings 82 (82a, 82b) and the pinion gear 85 from the shield plate 86 (86a, 86b). Rack members 87 (87a, 87b) that extend in the direction and mesh with the pinion gear 85. Further, the shielding plate 86 (86a, 86b) has both side edges 88 (88a, 88b), 89 (89a, 89b) along the longitudinal direction of the fixing device 100 by rails 90, 91 provided on the substrate 81. It is guided and configured to be movable along the longitudinal direction of the fixing device 100.

  Accordingly, by driving the pinion gear 85, the shielding plates 86 (86a, 86b) move along the longitudinal direction of the fixing device 100. 8 shows a state in which the shielding plate 86 (86a, 86b) completely shields each opening 82 (82a, 82b), and FIG. 9 shows the shielding plate 86 (86a) by driving the pinion gear 85. 86b) shows a state in which the openings 82 (82a, 82b) are slightly opened by moving to the center where the pinion gear 85 is arranged in the direction of each other.

  The moving state of the shielding plate 86 (86a, 86b) is detected by the position detection means, and the detection signal is transmitted to the control means 171. The control means 171 determines whether or not the movement of the regulating member 83, that is, the shielding plate 86 is abnormal. In the present embodiment, as shown in FIG. 6, the position detecting means is provided on the shielding plate 86b, and a detected member 92 that moves together with the shielding plate 86b, and detection sensors 93 that are arranged at both ends in the movement direction of the shielding plate 86b. , 94. By providing the detected member 92 with a plurality of detected portions 92a, 92b, 92c, a plurality of movement positions can be detected.

  The sheet passing area and the non-sheet passing area used in the description are as follows.

  As shown in FIG. 7, a small size paper having a smaller size in the width direction than the A3 size (maximum paper passing size (b-1) of the apparatus), for example, a small size paper such as A4R, B5 (paper passing size (b 3)) passes through the fixing area, the maximum fixing area (b-3) through which the small size paper passes is a paper passing area, and the area (b-2) other than the paper passing area is not passed. It is a paper area.

  In other words, the non-sheet passing area (b-2) is an area obtained by subtracting a fixing area when a small size paper passes with respect to a width in the fixing longitudinal direction (small size paper with respect to the width in the fixing longitudinal direction). Area other than the sheet passing area).

  When the cooling control by the cooling device 70 described above is performed, the regulating member 83 that adjusts the area for sending the cooling air to the non-sheet passing area to the optimum width according to the width of the small size paper, that is, the shielding plate As shown in FIG. 8, the shielding plate 86 is driven by an opening width adjusting member, that is, a restricting member driving means 84 to adjust the opening width of the blower opening 82 according to the width of the small size paper.

  Further, in order to adjust the opening width of the shielding plate 86 according to a plurality of small size papers, as shown in FIG. 6, the position detection means, that is, the sensor 93 for detecting the home position of the shielding plate 86 and the opening width. The aperture width is adjusted by an aperture width detection sensor 94 that adjusts the aperture to a predetermined size.

  Next, the cooling mechanism control of the fixing device 100 in this embodiment will be described.

  The objects of the present invention are as follows. In other words, when small-size paper is continuously passed, there is a means for cooling the non-sheet-passing area for the problem that the temperature of the end of the fixing device that becomes the non-sheet-passing area rises. In an image forming apparatus provided with a shielding plate for optimizing the image quality, the object is to prevent the ripple from spreading to other parts of the apparatus and to continue the operation of the apparatus when a failure occurs in the cooling means or the shielding means. . Hereinafter, device control when a failure of the cooling mechanism occurs will be specifically described.

  FIG. 10 shows an operation flowchart when the regulating member, that is, the shielding plate 86 cannot be moved.

  When printing a small size paper, or when the temperature detected by the fixing device end temperature measuring thermistor 56 (FIG. 6) exceeds a predetermined temperature, the shielding plate 86 is moved to a predetermined position. During the movement of the shielding plate, the presence / absence of an error is detected (S30). If the movement of the shielding plate 86 is abnormal, that is, an error has occurred, the control means 171 determines whether or not the shielding plate 86 at that time is in a position to shield the blower fan 73 (S31). .

  In the present embodiment, the case where the shielding plate 86 is located at a position where the cooling air from the blower fan 73 is shielded will be described as a home position.

  When the position of the shielding plate 86 is at the home position, the control unit 171 continues the image forming operation, that is, the printing operation without operating the blower fan 73. Then, when a small-size paper continuous printing operation or the like is performed and the temperature rise of the non-sheet passing portion is detected by the end temperature measuring thermistor 56, the surface temperature of the non-sheet passing region is equal to the surface temperature of the sheet passing region. In order to cool to the same extent, control is performed to reduce the device productivity and increase the idling time.

  Then, the printing operation is resumed when the non-sheet-passing area temperature is lowered to a predetermined temperature (S33).

  The above-described control for reducing the apparatus productivity, extending the idling operation time, and lowering the temperature of the non-sheet passing area is hereinafter referred to as “down sequence”. A detailed description of the down sequence control will be described later.

  Next, when the shielding plate 86 is stopped at a position other than the home position, it is notified that an error of the shielding plate has occurred, and the image forming operation is prohibited and stopped (S34). This is because when the blower fan 73 is not blocked by the shielding plate 86 and the image forming operation is continued without driving the blower fan 73, the temperature of the blower fan 73 rises and heat resistance is improved. This is because a low fan may cause a failure.

  As described above, according to the present embodiment, when an abnormality occurs in the moving unit 84, whether or not to perform the subsequent image forming operation is selected by the selection unit (control unit) 171 according to the stop position of the regulating member 83. The

  In this embodiment, by performing the above-described control, even when an error (abnormality) occurs in the movement of the shielding plate 86, the image forming operation can be continued depending on the stop position of the shielding plate 86. It is. For this reason, even when an apparatus failure occurs, the image forming operation can be continued as much as possible, so that an image forming apparatus with high usability can be provided.

  In the first embodiment, when an operation error of the shielding plate 86 is detected (S30), an alarm may be displayed on the operation unit 172 as in the modified embodiment shown in FIG. It is. The subsequent operation is the same as the operation shown in FIG.

  An example of alarm display on the operation unit 172 is shown in FIG. By displaying an alarm as shown in FIG. 12, it is possible to prompt a serviceman to repair the device, and to clearly inform the user why the device productivity has decreased due to the implementation of the down sequence. Is possible.

  An example of the error detection method of the shielding plate movement in the present embodiment is shown in FIG.

  After the shielding plate movement control is started, the input of the opening width detection sensor 94 which is the restricting member position detecting means is waited for a predetermined time (S20, S21). If there is no input to the control means 171 of the opening width detection sensor 94 for a predetermined time, the control means 171 determines that the shielding plate 86 has not moved and determines an error (abnormality).

  Note that the error detection method is an example, and the present invention is not limited to this. For example, if the drive motor Mo, which is the shielding plate drive source, is not driven by a predetermined load, an error signal is transmitted. Even if the error detection signal is monitored by the control means 171, error detection is performed. Can be done.

  Next, an example of the down sequence operation described in the first embodiment will be described below.

  As described in the first embodiment, when the shielding plate 86 cannot be moved, a small size having a short length in the main scanning direction is continuously passed with respect to the maximum paper width that the apparatus can pass. In the case of paper, the down sequence execution determination is performed according to the temperature detected by the fixing end temperature measuring thermistor 56.

  The determination of the down sequence is made for each image forming sheet. When the thermistor detection temperature is higher than a predetermined value, the one-stage productivity is lowered from the previous productivity. An example of a table defining productivity is shown in Table 1.

  From Table 1, for example, when an image forming operation is performed at a productivity of 30 sheets per minute in normal times, and when the thermistor detection temperature exceeds a predetermined value, the first stage of the down sequence level The productivity is reduced to 10 sheets per minute. By selecting such a mode for reducing productivity, a space between pages is widened, and a state in which a sheet is not caught in the fixing device, that is, an idle rotation time is increased. Further, when the idling rotation time increases, the temperature of the non-sheet passing area decreases, and the temperature difference between the sheet passing area and the non-sheet passing area decreases.

  Even after the first stage of the down sequence level, every time the temperature detected by the fixing device end temperature measurement thermistor 56 exceeds a predetermined value, the down sequence level is lowered, and the idling time is increased. The forming operation is continued. The above is an example of the down sequence operation.

  In the first embodiment, the non-sheet passing portion temperature is described as the determination condition in the determination of the down sequence execution after the timing of the shielding plate movement and in addition to the abnormal operation of the shielding plate movement. Went. However, the present invention is not limited to this. For example, a configuration in which the accumulated time from the start of the image forming operation is used for the determination of the start of moving the shielding plate and the execution of the down sequence, or the determination is made uniformly based on the paper size. Etc. can also be implemented. If a configuration is used in which uniform judgment is made based on the paper size, it is possible to adopt a configuration in which the down sequence is not entered when the paper size is large.

Example 2
FIG. 14 is a flowchart according to another embodiment when the shielding plate 86 cannot be moved in the image forming apparatus having the same configuration as that of the first embodiment.

  In the present embodiment, a description will be given of a configuration in which image formation can be performed without stopping the apparatus when the shielding plate 86 can no longer be moved and the shielding plate 86 is stopped at any position. .

  When printing a small size paper, or when the temperature detected by the edge measurement thermistor 56 exceeds a predetermined temperature, the shielding plate 86 is moved to a predetermined position. During the movement of the shielding plate, the presence / absence of an error is detected (S1). Even if an error occurs, the printing operation is continued (S2). When an error occurs, it is determined whether or not the shielding plate 86 at that time is in the home position (S3). If the shielding plate 86 is at the home position, the printing operation is continued as it is. Subsequent operations (S5, S6) are the same as the operations (S32, S33) of the first embodiment shown in FIG.

  When the shielding plate 86 is stopped at a position other than the home position, a mode is selected in which the blower fan 73 is driven to continue the printing operation (S4). The purpose of this is to prevent an increase in the temperature of an inexpensive fan with low heat resistance, and thus failure.

  At this time, the air volume of the blower fan 73, that is, the driving speed is set to a lower speed than the normal driving speed. The purpose of driving the blower fan 73 when the shielding plate movement error occurs is to prevent the temperature rise of the blower fan 73 itself. Therefore, in order to prevent the cooling air from flowing into the fixing device 100 unnecessarily, the fan is driven at a lower fan driving speed than during normal operation.

  Alternatively, the air volume of the blower fan 73 can be changed according to conditions such as the image forming speed, the type of paper on which the image is formed, the fixing device temperature, and the like. Or it is good also as a structure which changes the air volume of the ventilation fan 73 according to a stop position when it stops in the state which the shielding board 86 cannot move. In any case, the purpose is to perform fine adjustment of the air volume in consideration of prevention of failure of the blower fan 73 and influence on image formation.

  After the printing operation is completed, the operation returns to the above operation (S5, S6).

  By performing the above-described control, the image forming operation is continued without enlarging the failure portion, even when the operation of the shielding plate 86 cannot be performed due to a failure and the stop position of the shielding plate 86 is any. It is possible.

Example 3
FIG. 15 is a flowchart of an embodiment in which an error (abnormality) occurs in the blower fan 73 when the shielding plate 86 cannot be moved in the image forming apparatus having the same configuration as that of the first embodiment. Indicates.

  According to the present embodiment, an error in the movement operation of the shielding plate 86 is detected (S12), and if the position of the shielding plate 86 is not the home position (S14), the presence / absence of failure of the blower fan 73 is detected. (S15). When an error of the blower fan 73 is detected, the blower fan 73 cannot be driven and cannot be shielded by the shielding plate 86, so that an error is immediately notified and the operation of the apparatus is stopped. When there is no error of the blower fan 73, the operation is the same as the operation (S5, S6) of the second embodiment shown in FIG.

  The failure of the blower fan 73 is due to the configuration in which the error detection signal is monitored by the control means 171 if the drive motor Mf as a drive source is not driven by a predetermined load. Error detection can be performed. In addition, the error detection method of a ventilation fan can also be implemented by other methods, such as performing rotation detection of a ventilation fan, This invention is not limited to this.

  By performing the control, the operation of the apparatus can be surely stopped when the apparatus failure range may be expanded.

  In each of the above embodiments, the image forming apparatus according to the present invention has been described as an electrophotographic full-color printer of an intermediate transfer system using an intermediate transfer belt. However, the image forming apparatus of the present invention is not limited to this. Instead, the principle of the present invention is an image forming apparatus known to those skilled in the art, such as a direct transfer type image forming apparatus that directly transfers a toner image onto a recording material conveyed by a recording material carrier, or a monochrome image forming apparatus. The same effect can be achieved by applying the same to the image forming apparatus.

1 is a schematic sectional view showing an embodiment of an image forming apparatus according to the present invention. 3 is a control block diagram of a control unit of the image forming apparatus. FIG. It is a block diagram which shows an image memory part in detail. It is a block diagram which shows an external I / F process part in detail. 5A is a schematic sectional view of a fixing device according to an embodiment, FIG. 5B is a schematic sectional view of a fixing film, and FIG. 5C is a schematic configuration of a ceramic heater. It is sectional drawing. It is a top view of a fixing device, and is a side view of a cooling device and a shielding device. FIG. 4 is an explanatory diagram of a sheet passing area and a non-sheet passing area in the fixing device. It is a front view of the shielding apparatus in a fixing device, and is a front view of the opening adjustment means provided with the shielding board. It is a front view of the shielding device in the fixing device, and is a front view of the opening adjusting means showing a state where the shielding plate has moved to the central portion. It is a flowchart of one Example when a shielding board movement abnormality generate | occur | produces. It is a flowchart of the other Example when a shielding board movement abnormality generate | occur | produces. It is a figure which shows an example of the alarm display of an operation part. It is a flowchart of one Example which detects shielding board movement abnormality. It is a flowchart of the other Example when a shielding board movement abnormality generate | occur | produces. It is a flowchart of one Example when a shielding board movement abnormality and a cooling fan abnormality generate | occur | produce. It is a figure which shows an example of the conventional fixing device.

Explanation of symbols

1 (1Y, 1M, 1C, 1Bk) Image forming unit 2 (2a, 2b, 2c, 2d) Photosensitive drum (image carrier)
3 (3a, 3b, 3c, 3d) Primary charger (charging means)
4 (4a, 4b, 4c, 4d) Developing device (developing means)
5 (5a, 5b, 5c, 5d) Transfer roller (primary transfer means)
6 (6a, 6b, 6c, 6d) Drum cleaner device (cleaner means)
7 Exposure equipment (exposure means)
8 Intermediate transfer belt (intermediate transfer member)
10 Secondary transfer counter roller 12 Secondary transfer roller (secondary transfer means)
50 Film assembly (first fixing member)
53 Fixing film 55, 56 Temperature detection sensor 60 Pressure roller (second fixing member)
70 Cooling device 71 Blower duct 72 Blower opening 73 Blower fan (Blower unit)
80 Shielding device 81 Substrate 82 (82a, 82b) Air outlet 83 (83a, 83b) Restricting member 84 Restricting member driving means (moving means)
85 Pinion gear 86 (86a, 86b) Shielding plate 87 (87a, 87b) Rack member 93, 94 Position detection sensor 100 Fixing device (image heating means)
171 Selection means (control means)
172 Operation unit

Claims (9)

Image forming means for forming an image on the recording material, image heating means for heating the image on the recording material, air blowing means for blowing air toward the air blowing port for cooling the image heating means, and opening width of the air blowing port In an image forming apparatus comprising: a regulating member that regulates the recording material according to the width of the recording material; and a moving unit that moves the regulating member.
An image forming apparatus, comprising: a selecting unit configured to select whether or not to perform a subsequent image forming operation according to a stop position of the restricting member when an abnormality occurs in the moving unit.   Subsequent image forming operation is prohibited when the restriction member has at least a part of the blower opening, and subsequent image forming operation when the restricting member covers all of the blower port. The image forming apparatus according to claim 1, wherein:   2. The image forming apparatus according to claim 1, wherein when the subsequent image forming operation is executed in a state where at least a part of the air blowing port is open, the air blowing unit is operated.   When a subsequent image forming operation is executed in a state where at least a part of the air blowing port is open, a mode for reducing the number of recording materials subjected to image heating processing per unit time can be selected. The image forming apparatus according to claim 3.   The air blowing condition of the air blowing unit is changed according to a stop position of the restricting member when a subsequent image forming operation is executed in a state where at least a part of the air blowing opening is open. Or 4 image forming apparatuses. Image forming means for forming an image on the recording material, image heating means for heating the image on the recording material, air blowing means for blowing air toward the air blowing port for cooling the image heating means, and opening width of the air blowing port In an image forming apparatus comprising: a regulating member that regulates the recording material according to the width of the recording material; and a moving unit that moves the regulating member.
An image forming apparatus capable of selecting a mode for operating the blowing unit when a subsequent image forming operation is executed in a state where at least a part of the blowing port is opened due to an abnormality of the moving unit. .   When the subsequent image forming operation is executed in a state where at least a part of the air blowing port is opened due to an abnormality of the moving means, a mode for reducing the number of recording materials to be subjected to image heating processing per unit time can be selected. The image forming apparatus according to claim 6, wherein the image forming apparatus is provided.   8. The image forming apparatus according to claim 7, wherein the number of recording materials subjected to image heating processing per unit time in the mode is changed according to a stop position of the restricting member. When the subsequent image forming operation is executed in a state where at least a part of the air blowing port is opened due to an abnormality of the moving means, the air blowing condition of the air blowing means is changed according to the stop position of the restricting member. The image forming apparatus according to claim 6, wherein the image forming apparatus is an image forming apparatus.

Images