JP2005156777A - Electrophotographic recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To evade decrease in printing accuracy and damage to an electrophotographic device while achieving energy saving by maintaining the temperature of use of inner parts without increasing fans. <P>SOLUTION: A means detecting the hours of operation is provided in the electrophotographic recording device and a cooling time (rotation period of the fan) according to the printing time is provided after printing termination. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrophotographic recording apparatus, for example, a laser beam printer that records (prints) an image on a cut sheet, OHT, or the like based on an image signal from a computer.

  FIG. 9 is a sectional view showing a schematic configuration of a color laser beam printer which is a conventional color image forming apparatus.

  This color laser printer includes four photosensitive drums 101 (101Y, 101M, 101C, and 101Bk) that are horizontally arranged, and these photosensitive drums are yellow (Y: Yellow), magenta (M: Magenta), and cyan. Four colors (C: Cyan) and black (Bk: Black) are individually formed and superimposed to create a color image. The photosensitive drum 101 is driven to rotate counterclockwise by a driving unit (not shown). A charging unit 102 (102Y, 102M, 102C, 102Bk) for uniformly charging the surface of the photosensitive drum 101 in order according to the rotation direction, and a laser beam is irradiated around the photosensitive drum 101 based on image information. A scanner unit 103 (103Y, 103M, 103C, 103Bk) as an exposure unit for forming an electrostatic latent image on the drum 101, and a developing unit for developing a toner image by attaching toner (developer) to the electrostatic latent image. (Developing roller) 104 (104Y, 104M, 104C, 104Bk), an intermediate transfer member 105 that sequentially transfers the toner image on the photosensitive drum 101, and a transfer material S on which the toner image superimposed and transferred to the intermediate transfer member 105 is conveyed. A secondary transfer roller 106 and the like as a secondary transfer means for transferring the toner image to the recording medium are disposed.

  Here, the photosensitive drum 101, the charging unit 102, and the developing unit 104 are integrally formed into a cartridge to form a process cartridge 107 (107Y, 107M, 107C, 107Bk), which is detachable from the color image forming apparatus. It has become.

  Next, the configuration of each unit will be described sequentially. For example, the photosensitive drum 101 is configured by applying an organic photosensitive conductor layer (OPC) to the outer peripheral surface of an aluminum cylinder. The photosensitive drum 101 is rotatably supported at both ends by a support member, and is driven to rotate counterclockwise by transmitting a driving force from a driving motor (not shown) to one end. .

  Each charging means 102 is a conductive roller formed in a roller shape. The roller is brought into contact with the surface of the photosensitive drum 1, and a charging bias voltage is applied to the roller by a power source (not shown). The surface of the body drum 101 is uniformly charged.

  The scanner unit 103 has a laser diode that emits light in response to an image signal, and irradiates light from the diode to a polygon mirror 103b fixed to a scanning motor 103a that rotates at high speed, and is reflected by the polygon mirror. Laser light is irradiated onto the photosensitive drum 101 rotating at a constant speed via the imaging lens 103c, and an electrostatic latent image is formed by selectively exposing the surface thereof.

  The developing means (developing roller) 104 (104Y, 104M, 104C, 104Bk) are respectively yellow (Y), magenta (M), cyan (C), black (from the upstream side in the transfer material conveyance direction (left side in the drawing). Bk) is composed of a developing device storing each color toner. When developing the electrostatic latent image on the photosensitive drum 101, the toner in the toner container of the corresponding developing device is fed by the feeding mechanism, and a thin layer of toner is applied to the outer periphery of the rotating developing roller 104, and the toner is charged. Apply (friction charging). By applying a developing bias between the developing roller 104 and the photosensitive drum 101 on which the electrostatic latent image is formed, toner is attached to the electrostatic latent image and developed as a toner image.

  An intermediate transfer member 105, which is an endless belt member that circulates and moves in contact with the 104 photosensitive drums 101Y, 101M, 101C, and 101Bk, is disposed.

  The intermediate transfer member 105 rotates in the clockwise direction in the figure in synchronism with the outer peripheral speed of the photosensitive drum 101 in order to multiplex-transfer the toner image on the photosensitive drum 101 visualized by each developing device during the color image forming operation. The transferred intermediate transfer body 105 sandwiches and conveys the transfer material S by a secondary transfer roller 106 to which a voltage is applied, thereby simultaneously transferring multiple color toner images on the intermediate transfer body onto the transfer material S.

  In this laser printer, a series of processes for recording a color image on a transfer material forms a toner image corresponding to each color separated on each photosensitive drum 101 by an image forming signal, and the toner image is transferred to an intermediate transfer member. A color image is formed by sequentially superimposing and transferring to 105. The transfer material S stored in the transfer material cassette 108 is conveyed to the secondary transfer portion by the feeding roller 9 and the conveyance roller 110 of the conveyance means so as to be synchronized with the image formation, and transferred to the transfer material S. Then, the transfer material S after the transfer of the toner image is conveyed to the fixing device 111 to apply heat and pressure to fix the toner image, and is discharged to the discharge portion 113 by the discharge roller 112. Reference numeral 114 denotes a cleaning unit for cleaning the toner remaining on the intermediate transfer member 105 after the toner image is transferred to the transfer material S.

The color laser printer apparatus includes an electronic circuit for controlling the apparatus as a heat source, a fixing device 111 for fixing, a motor for transferring the transfer material, and moving the apparatus. Therefore, the internal temperature of the apparatus rises as the apparatus continues to operate. Therefore, a cooling fan 115 for taking in (discharging) air is provided in order to cool these heat generation reductions, and the cooling fan continues to rotate for a certain period of time until the temperature inside the apparatus has dropped even after printing is completed. .
JP 2002-091121 A

  However, in the above-described conventional example, if the print processing capacity increases, the temperature inside the apparatus rises above the cooling capacity of the cooling fan. The operating temperature of each part may be exceeded. FIG. 10 shows that when a device is continuously used, a certain component exceeds the component use limit temperature. For this reason, it is necessary to keep the cooling fan running for a certain period of time until the internal temperature of the device has been reduced even after printing is completed, and even when the number of printed sheets is small, cooling is performed for a certain period of time. It was against the decline and energy saving.

  In view of the above problems, the invention of the present application has been made.

  The object of the first invention according to the present application is to minimize the cooling time.

  The purpose of the second and third inventions according to the present application is to further optimize the cooling time and maximize the apparatus operating time, while keeping the operating temperature of the internal components of the apparatus.

  An object of the fourth to sixth inventions according to the present application is to predict the temperature rise inside the apparatus from a computer printing command and to minimize the cooling time.

  An object of the seventh and eighth inventions related to the present application relates to an apparatus provided with a double-sided printing means. When fixing on the first side of printing is completed, transfer with heat after fixing is performed when printing on the second side. By circulating the material inside the apparatus, it is necessary to keep the operating temperature of the part by minimizing the cooling time in consideration of the influence of the temperature rise inside the apparatus due to the heat of the transfer material after fixing.

To achieve the above objective,
According to a first aspect of the present application, the electrophotographic recording apparatus is provided with means for detecting an operation time, and a cooling time corresponding to the operation time is provided after the operation.

  The shortest cooling time required for lowering the temperature could be determined from the state of temperature increase according to the present invention.

  The second invention according to the present application is characterized in that the cooling time is constant until a certain time T1 and the cooling time corresponds to the working time when T1 is exceeded.

  With this configuration, it is possible to set a cooling time in consideration of a rapid temperature rise by a fixing device or the like regardless of the number of sheets generated in the initial operation of the apparatus.

  In the third invention according to the present application, when the operation time exceeds a certain time T2, the operation enters a dormant state even during operation, takes a cooling time corresponding to the operation time until the operation is stopped, and resumes operation after the cooling time has passed. And performing the rest of the work.

  With this configuration, in the case of an operating time when the temperature rise exceeds the operating temperature limit of the internal parts of the device, since it enters the dormant state at the previously determined limit operating time (time that does not exceed the operating temperature limit of the internal components of the device), The operating temperature of the internal parts of the device can be protected.

  A fourth invention according to the present application is characterized in that the electrophotographic recording apparatus knows the continuous recording number from a printing command from a computer and has a cooling pause time corresponding to the recording number after the printing is completed.

  According to the present invention, the cooling time required for lowering the temperature can be known without having a timer or the like from the state where the temperature has been increased.

  The fifth invention according to the present application is characterized in that the cooling time is constant up to a certain number S1 of recording sheets and has a cooling time corresponding to the number of recordings when exceeding S1.

  With this configuration, it is possible to set a cooling time in consideration of a rapid temperature rise by a fixing device or the like regardless of the number of sheets generated in the initial operation of the apparatus.

  The sixth invention according to the present application enters a pause state even during operation when the number of recorded sheets exceeds a certain number S2, takes a cooling time corresponding to the number of recorded sheets until the pause, and resumes operation after the cooling time has passed. And performing the rest of the work.

  With this configuration, in the case of the number of recordings where the temperature rise is equal to or higher than the use limit temperature of the internal parts of the device, the pause state is entered with the previously determined limit recording number (the number not exceeding the use temperature limit of the internal parts of the device). The operating temperature of the internal parts of the device can be protected.

  A seventh invention according to the present application is characterized in that, in an apparatus having a double-sided printing function, the cooling time is determined from the operating time of both sides. This makes it possible to maximize the processing capacity of the apparatus without exceeding the operating temperature of the internal parts of the apparatus.

  An eighth invention according to the present application is characterized in that, in an apparatus having a double-sided printing function, the cooling time is determined from the number of recordings on both sides. This makes it possible to maximize the processing capacity of the device without exceeding the operating temperature of the internal parts of the device without having a timer for measuring the operating time.

As explained above,
According to the first aspect of the present application, the electrophotographic recording apparatus is provided with means for detecting the operation time, and the apparatus cooling time corresponding to the operation time is provided after the operation.

  As a result, it was possible to set the shortest cooling time necessary to protect the operating temperature of the internal components of the apparatus and to avoid deterioration of printing accuracy and damage to the apparatus.

  According to the second invention of the present application, the cooling time is constant until a certain time T1, and when the operating time exceeds T1, the cooling time corresponding to the operating time is provided.

  As a result, it is possible to set a pause time in consideration of a rapid temperature rise caused by a fixing device or the like at the initial stage of operation of the apparatus regardless of the printing time.

  According to the third invention of the present application, when the operation time exceeds a certain time T2, the operation enters a dormant state even during operation, takes a cooling time corresponding to the operation time until the operation stops, and operates after the cooling time has passed. Resume and do the rest of the work. As a result, in the case of an operating time when the temperature rise exceeds the operating temperature limit of the internal parts of the device, the device enters a dormant state at a predetermined operating time (a time not exceeding the operating temperature limit of the internal components of the device). The operating temperature of internal parts can be protected.

  According to the fourth invention of the present application, the electrophotographic recording apparatus knows the number of recordings from a printing command from a computer, and has a cooling time corresponding to the number of recordings.

  As a result, the cooling time required for lowering the temperature can be obtained without having a timer or the like from the state where the temperature has been raised.

  According to the fifth aspect of the present application, the cooling time is constant up to a certain number S1 of recording sheets, and the cooling time corresponding to the number of recordings is provided when S1 is exceeded.

  As a result, it is possible to set a cooling time in consideration of a rapid temperature rise caused by a fixing device or the like at the initial stage of operation of the apparatus regardless of the number of prints.

  According to the sixth aspect of the present application, when the number of recorded sheets exceeds a certain number S2, the apparatus enters a pause state even during operation, takes a cooling time corresponding to the number of recorded sheets until the pause, and operates after the cooling time has passed. Resume and do the rest of the work.

  As a result, in the case where the number of recordings is such that the temperature rise is equal to or higher than the operating temperature limit of the internal parts of the device, the apparatus enters the resting state with the previously determined limit recording number (the number not exceeding the operating temperature limit of the internal parts of the device). The operating temperature of internal parts can be protected.

  According to the seventh invention of the present application, in a device having a double-sided printing function, the cooling time is determined from the operating time of both sides. This makes it possible to maximize the processing capacity of the apparatus without exceeding the operating temperature of the internal parts of the apparatus.

  According to the eighth invention of the present application, in an apparatus having a double-sided printing function, the cooling time is determined from the number of recordings on both sides. This makes it possible to maximize the processing capacity of the device without exceeding the operating temperature of the internal parts of the device without having a timer for measuring the operating time.

(First embodiment)
FIG. 2 is a schematic sectional view of the color laser printer according to the first embodiment of the present invention.

  This color laser printer includes four photosensitive drums 1 (1Y, 1M, 1C, 1Bk) arranged in a vertical direction, and these photosensitive drums are yellow (Y: Yellow), magenta (M: Magenta), and cyan. Four colors (C: Cyan) and black (Bk: Black) are individually formed and superimposed to create a color image. The photosensitive drum 1 is rotationally driven counterclockwise by a driving unit (not shown). A charging means 2 (2Y, 2M, 2C, 2Bk) for uniformly charging the surface of the photosensitive drum 1 in order according to the rotation direction, and a laser beam is irradiated around the photosensitive drum 1 based on image information. A scanner unit 3 (3Y, 3M, 3C, 3Bk) as an exposure unit for forming an electrostatic latent image on the drum 1, and a developing unit for developing a toner image by attaching toner (developer) to the electrostatic latent image. (Developing roller) 4 (4Y, 4M, 4C, 4Bk), an intermediate transfer body 5 for sequentially transferring the toner image on the photosensitive drum 1, and a transfer material S on which the toner image superimposed on the intermediate transfer body 5 is conveyed. A secondary transfer roller 6 or the like serving as a secondary transfer means for transferring to is disposed.

  Here, the photosensitive drum 1, the charging unit 2, and the developing unit 4 are integrally formed into a cartridge to form a process cartridge 7 (7Y, 7M, 7C, 7Bk), which is detachable from the color image forming apparatus. It has become.

  Next, the configuration of each unit will be described sequentially. The photosensitive drum 1 is configured by, for example, applying an organic photosensitive conductor layer (OPC) to the outer peripheral surface of an aluminum cylinder. The photosensitive drum 1 is rotatably supported at both ends by a support member, and is driven to rotate counterclockwise by transmitting a driving force from a driving motor (not shown) to one end. .

  Each charging means 2 is a conductive roller formed in the shape of a roller. The roller is brought into contact with the surface of the photosensitive drum 1, and a charging bias voltage is applied to the roller by a power source (not shown), thereby exposing the photosensitive drum. The surface of the body drum 1 is uniformly charged.

  The scanner unit 3 has a laser diode that emits light in response to an image signal. The scanner unit 3 irradiates light from the diode onto a polygon mirror 3b fixed to a scanning motor 3a that rotates at high speed, and the reflected light is applied to an imaging lens 3c. Is applied to the photosensitive drum 1 rotating at a constant speed, and the surface thereof is selectively exposed to form an electrostatic latent image.

  The developing means (developing rollers) 4 (4Y, 4M, 4C, 4Bk) are respectively yellow (Y), magenta (M), cyan (C), black from the upstream side (lower side in the figure) in the transfer material conveyance direction. (Bk) is composed of a developer that stores toner of each color. When developing the electrostatic latent image on the photosensitive drum 1, the toner in the toner container of the corresponding developing device is fed by the feeding mechanism, and a thin layer of toner is applied to the outer periphery of the rotating developing roller 4 and the toner is charged. Apply (friction charging). By applying a developing bias between the developing roller 4 and the photosensitive drum 1 on which the electrostatic latent image is formed, toner is attached to the electrostatic latent image and developed as a toner image.

  An intermediate transfer member 5 that is an endless belt member that faces the four photosensitive drums 1Y, 1M, 1C, and 1Bk and circulates so as to be in contact therewith is disposed.

  The intermediate transfer member 5 rotates in the clockwise direction in the figure in synchronism with the outer peripheral speed of the photosensitive drum 1 in order to multiplex-transfer the toner image on the photosensitive drum 1 visualized by each developing device during the color image forming operation. The transferred intermediate transfer body 5 sandwiches and conveys the transfer material S by a secondary transfer roller 6 to which a voltage is applied, thereby simultaneously transferring multiple color toner images on the intermediate transfer body onto the transfer material S.

  A series of flows for recording a color image on the transfer material in the laser printer is based on a print signal from the outside of the apparatus, and forms a toner image corresponding to each color separated on each photosensitive drum 1 and the toner. The image is sequentially superimposed and transferred to the intermediate transfer member 5 to form a color image. The transfer material S stored in the transfer material cassette 8 is conveyed to the secondary transfer portion by the feeding roller 9 and the conveyance roller 10 of the conveying means so as to be synchronized with the image formation, and transferred to the transfer material S. Then, the transfer material S after the transfer of the toner image is conveyed to the fixing device 11 and the toner image is fixed by applying heat and pressure, and is discharged to the discharge portion 13 by the discharge roller 12. Reference numeral 14 denotes a cleaning unit for cleaning the toner remaining on the intermediate transfer body 5 after the toner image is transferred to the transfer material S.

  In addition, the color laser printer apparatus includes an electronic circuit for controlling the apparatus as a heat source, a fixing device 11 for fixing, a motor for transferring the transfer material and moving the apparatus. Therefore, the internal temperature of the apparatus rises as the apparatus continues to operate. Therefore, a cooling fan 15 is provided for taking in (discharging) air in order to cool these heat loss. Furthermore, it has a timer (not shown) that measures the time during which the color laser printer is operating.

  In the printing process of this laser printer, when the color laser printer receives the print signal, after performing the printing according to the print signal, the motor for supplying power to the heating of the fixing device and the conveyance of the transfer material is stopped. Then, it enters a cooling state in which it is activated with a cooling fan and minimum power. The cooling state time is determined from the operation time (printing time) obtained from the timer. For example, as shown in FIG. 1, the cooling time is set so as to satisfy the relationship of printing time (operation time): pause time = 1: 1.

  The temperature rise inside the apparatus increases with the operation time, and a correlation is established between the operation times. In addition, the time required to lower the temperature from the raised temperature to a certain temperature is related to the cooling capacity and cooling time of the cooling fan, and the cooling capacity is normally constant. Correlates with time. Therefore, it is possible to obtain the cooling time from the operating time as in the present invention.

  According to the present invention, it is possible to suppress the temperature rise inside the apparatus, and it is possible to avoid exceeding the component use temperature as shown in FIG. The details of the temperature transition in FIG. 3 are shown in FIG. 4, which has a cooling time after printing, and as a result, the temperature rises and falls as a whole while repeating the rise and fall of the temperature. However, as shown in FIG. The temperature stabilizes without exceeding the limit temperature. As a result, it was possible to avoid the deterioration of printing accuracy and the occurrence of fatal damage (for example, fixing of the developer) to the apparatus (color laser printer). In addition, the shortest cooling time was set so as not to reduce the operating efficiency of the equipment.

  As a modification of this embodiment, in this embodiment, the cooling time is determined from the operation time measured by a timer, but the operation time is usually proportional to the number of prints. For example, in a 16 ppm (print per minute) color laser printer, if 16 sheets are printed, the operation is about 1 minute. Therefore, it is possible to obtain the cooling time from the number of prints. In this modification, the cooling time is determined from the number data included in the print signal sent to the color laser printer, and the cooling time is taken at the end of printing. . Also in this modification, the same effect as the first embodiment can be obtained.

(Other embodiments)
(Second Embodiment)
FIG. 5 shows the relationship between the cooling time and the printing time (operation time) of the color laser printer according to the second embodiment of the present invention. In this embodiment, until the time from the start of printing to the end of printing until T1, the cooling time after the end of printing is a certain time, and for the time exceeding T1, the cooling time increases in proportion to the printing time. And

  According to the present invention, in order to cope with a rapid temperature rise by the fixing device regardless of the number of prints in the initial stage of operation, a small number of prints are allowed to have a constant cooling time so as to cope with a temperature rise in the initial stage of operation of the apparatus. The cooling time can be set finely.

  As a modification of the present embodiment, the cooling time is substituted with the number of prints without using a timer. In this modification, a constant cooling time is used until the number of printed sheets is up to S1, and the cooling time is increased in proportion to the number of printed sheets when the number exceeds S1. This modification also has the same effect as the second embodiment.

(Third embodiment)
FIG. 6 shows the relationship between the cooling time and the printing time (operation time) of the color laser printer according to the third embodiment of the present invention.

  When printing is performed without pause during printing, printing is stopped when a certain time T2 (time that does not exceed the component use limit temperature) is reached in the present embodiment when printing with a long print time of T3. After entering the pause state, after the cooling time T2 (when the ratio of the cooling time and the printing time is 1: 1), printing is resumed, and the remaining printing is performed, and T3 + T2 (when T3 <2 × T2) ) Finish printing in time.

  Conventionally, since printing is performed for T3 hours without stopping in the middle, as shown in FIG. 6, the use limit temperature of the component is exceeded at T3 time, so that the printing accuracy is deteriorated and the apparatus (color laser printer) is fatal. Damage (for example, fixing of the developer) was given. However, in the present embodiment, the component usage limit is entered even when the apparatus enters the rest state before the component usage limit temperature is exceeded, the temperature of the apparatus is lowered while the cooling time T2 elapses, and printing is resumed to finish the remaining printing. It was possible to avoid exceeding the temperature. As a result, it was possible to avoid the deterioration of printing accuracy and the occurrence of fatal damage (for example, fixing of developer) to the apparatus (color laser printer).

  As a modification of the present embodiment, the cooling time is substituted with the number of prints without using a timer. In this modification, when printing the number of prints S3 exceeding the component use limit temperature, when the number of prints S2 (time not exceeding the component use limit temperature) is reached, printing is stopped and the printer enters a rest state, and the number of prints S2 After a lapse of the cooling time (if the ratio between the pause time and the time for printing S2 sheets is 1: 1), printing is resumed and the remaining printing is performed, and S3 + S2 (when S3 <2 × S2) ) Finish printing in time. Such a modified embodiment has the same effect as that of the third embodiment.

(Fourth embodiment)
FIG. 7 shows a color laser printer according to the second embodiment of the present invention. In the present embodiment, four photosensitive drums 1 (1Y, 1M, 1C, 1Bk) are provided in the vertical direction, and these photosensitive drums are yellow (Y: Yellow), magenta (M: Magenta), and cyan. Four colors (C: Cyan) and black (Bk: Black) are individually formed and superimposed to create a color image. Furthermore, it has a function of printing both front and back surfaces of the transfer material S. The process of printing both surfaces is a process as shown in the first embodiment, and first the surface is printed. In the final process of printing on the front surface, heat and pressure are applied to the transfer material S in the fixing device 11 to fix the toner image, and when the rear end of the transfer material S passes through the branch path 17, the back-printing process is performed. Is started. First, the conveyance roller 10 after fixing is reversely rotated, and the transfer material S is conveyed to the reverse path 18 with its conveyance direction reversed. Thereafter, the sheet is conveyed again to the secondary transfer roller 6 and printing is performed on the surface in the same manner as printing. This time, after passing through the fixing device 11, the sheet is discharged to the discharge unit 13 by the carry-out roller 12. In the present embodiment, the means for detecting the operation time includes a means for detecting the time for duplex printing that occupies the operation time. This time is set as a double-sided printing time.

  In this embodiment, the cooling time is determined from the double-sided printing time. For example, the duplex printing time and the cooling time are set to a ratio of 1: 1. In single-sided printing, the cooling time is set to a certain short time.

  According to the present embodiment, FIG. 8 shows the temperature rise of single-sided printing and double-sided printing for a part whose component use limit temperature is 45 ° C. As shown in this figure, the internal temperature of the apparatus stops rising after about 60 minutes during single-sided printing and is within the component use limit temperature, whereas the internal temperature of the apparatus exceeds the component use limit temperature during double-sided printing. This is because the transfer material S to which heat has been applied by the fixing device 11 is conveyed by the reversing path 18 and the temperature inside the apparatus is raised by the heat of the transfer material S while the back surface is printed. Therefore, in single-sided printing, the cooling after the operation (printing) of the apparatus is set to a constant short time regardless of the printing time, and the cooling time of the apparatus is variable only in duplex printing corresponding to the duplex printing time. As a result, it was possible to avoid dropping the print processing capacity in single-sided printing. In double-sided printing, it was possible to perform printing without changing the component use limit temperature by having an optimal cooling time.

  As a modification of this embodiment, in this embodiment, the cooling time is determined from the double-sided printing time measured by a timer, but the double-sided printing time is usually proportional to the number of double-sided printed sheets, so that the cooling time is shorter than the number of double-sided printed sheets. In this variation, the cooling time is determined from the double-sided printed sheet number data included in the print signal sent to the color laser printer, and the cooling time is taken at the end of printing. Also in this modified embodiment, the same effect as in the fourth embodiment can be obtained.

It is the figure which showed the relationship between the cooling time in the color laser printer which is the 1st Embodiment of this invention, and printing time. 1 is a schematic sectional view of a color laser printer according to a first embodiment of the present invention. It is the figure which showed the temperature transition of the color laser printer internal component in the 1st Embodiment of this invention. FIG. 4 is an enlarged view of the time axis of FIG. 3. It is a figure which shows the relationship between the printing time and cooling time in the 2nd Embodiment of this invention. It is a figure which shows the relationship between the printing time and cooling time in the 3rd Embodiment of this invention. FIG. 6 is a schematic sectional view of a color laser printer that is a fourth embodiment of the present invention equipped with a double-sided mechanism. The figure which shows the apparatus internal temperature rise in single-sided printing and double-sided printing. It is a schematic sectional drawing which shows the conventional color laser printer. It is a figure which shows the internal component temperature transition of the conventional color laser printer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Photosensitive drum 2,102 Charging means 3,103 Scanner unit 4,104 Developing means 5,105 Intermediate transfer body 6,106 Secondary transfer roller 7,107 Process cartridge 8,108 Transfer material cassette 9,109 Feed Low 10,110 Conveying roller 11,111 Fixing 12,112 Discharging roller 13,113 Discharging unit 14,114 Cleaning unit 15,115 Cooling fan 17 Branching path 18 Reversing path

Claims (8)

  A latent image is formed on the surface of the photoreceptor with an exposure device, the image on which the developer is placed is transferred to a transfer material, and the image is fixed on the transfer material by applying heat, pressure, etc. to the transfer material. The electrophotographic recording apparatus for recording has a cooling means for cooling the inside of the electrophotographic recording apparatus and means for knowing the operation time of the apparatus, and the cooling time until the cooling means stops after the operation of the apparatus is stopped. An electrophotographic recording apparatus characterized in that the time corresponds to the operating time.   An electrophotographic recording apparatus characterized in that the cooling time is constant until the operating time exceeds a certain time T1, and when the operating time exceeds T1, the cooling time corresponds to the operating time after the operation is completed.   2. The apparatus according to claim 1, wherein when the operation time exceeds a certain time T2, the electrophotographic recording apparatus temporarily stops even during operation, enters a dormant state, and takes a cooling time corresponding to the operation time until the dormancy. 2. The electrophotographic recording apparatus according to 2.   A latent image is formed on the surface of the photoreceptor with an exposure device, the image on which the developer is placed is transferred to a transfer material, and the image is fixed on the transfer material by applying heat, pressure, etc. to the transfer material. The recording electrophotographic recording apparatus has a cooling means for cooling the inside of the electrophotographic recording apparatus and a means for detecting the number of recordings, and records the cooling time until the cooling means stops after the operation of the apparatus is completed. An electrophotographic recording apparatus characterized in that the time corresponds to the number of sheets.   The electrophotographic recording apparatus is characterized in that the cooling time is constant up to a certain number S1 of recording sheets, and when S1 is exceeded, a cooling time corresponding to the number of recording sheets is provided after the operation is completed.   5. The recording apparatus according to claim 4, wherein when the number of recordings exceeds a certain number S2, the electrophotographic recording apparatus temporarily stops even during operation and enters a resting state, and takes a cooling time corresponding to the number of recordings until the resting. 5. The electrophotographic recording apparatus according to 5.   A latent image is formed on the surface of the photoreceptor with an exposure device, the image on which the developer is placed is transferred to a transfer material, and the image is fixed on the transfer material by applying heat, pressure, etc. to the transfer material. The electrophotographic recording apparatus for recording has means for recording images on both the front and back surfaces of the transfer material, and the operation time according to claims 1 to 3 is an operation time only for double-side recording. The electrophotographic recording apparatus according to 1 to 3. A latent image is formed on the surface of the photoreceptor with an exposure device, the image on which the developer is placed is transferred to a transfer material, and the image is fixed on the transfer material by applying heat, pressure, etc. to the transfer material. The electrophotographic recording apparatus for recording has means for recording images on both the front and back sides of the transfer material, and the number of recordings according to claims 4 to 6 is the number only for double-sided recording. The electrophotographic recording apparatus according to -6.

Images