JP5050474B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus, and in particular, does not require a cooling unit such as a temperature sensor for detecting the temperature of a power supply apparatus that supplies power to the image forming apparatus or a fan for cooling the power supply apparatus, and an optional tray. The present invention relates to an image forming apparatus capable of preventing overheating of the power supply apparatus even when a large load is applied to the power supply apparatus as in the case of mounting the power supply.

  In color image forming apparatuses such as copying machines and printers to which an electrophotographic system is applied, a toner image formed on a photosensitive member such as a photosensitive drum is transferred to an intermediate transfer member such as an intermediate transfer belt or an intermediate transfer drum. Then, a so-called intermediate transfer system in which the toner is transferred onto a recording medium such as fine paper and fixed is widely used.

  Among the intermediate transfer type image forming apparatuses, in the aspect having the photosensitive drum and the intermediate transfer belt, the photosensitive drum is charged by the charging device, and the surface is imagewise exposed by the exposure device to electrostatic latent image on the surface of the photosensitive member. Form an image. Then, the toner is transferred from the toner developing device to form a toner image on the surface of the photosensitive drum.

  Here, since the intermediate transfer belt and the primary transfer roller are arranged so that the intermediate transfer belt comes into curved contact with the surface of the photosensitive drum by the primary transfer roller, the toner image on the photosensitive drum is caused by the action of the transfer roll. Primary transfer is performed on the intermediate transfer belt.

  This process is repeated for each color of yellow (Y), magenta (M), cyan (C), and black (K), and toner images of four colors Y, M, C, and K are superimposed on the intermediate transfer belt. The Then, the four color toner images on the intermediate transfer belt are secondarily transferred to the recording medium by the secondary transfer roll.

  A color image is formed on the recording medium by fixing the toner image secondarily transferred onto the recording medium.

In the image forming apparatus of the above aspect, there is provided a cleaning device that removes transfer residual toner remaining on the surface of the intermediate transfer belt after the secondary transfer. The belt cleaning device is disposed downstream of the secondary transfer position in the moving direction of the intermediate transfer belt and upstream of the position where the intermediate transfer belt contacts the photoconductive drum. The cleaning device includes a charging roller that charges the transfer residual toner to a polarity opposite to the normal charging polarity. Therefore, in the image forming apparatus, the transfer residual toner is transferred to the photoconductor drum and the surface of the photoconductor The toner image is transferred to the intermediate transfer member at the same time (Patent Document 1).
Japanese Patent No. 3267507

  However, in these image forming apparatuses, in recent years, miniaturization and space saving have progressed, and a layout in which components are arranged without gaps has become common. Further, a fan for cooling the inside of the image forming apparatus tends to be omitted. For this reason, when the image forming apparatus is operated, heat is easily generated inside and the temperature easily rises. In particular, a motor for driving a toner developing unit that develops a latent image on the surface of the photosensitive drum with toner, and a sheet in the image forming apparatus A load is likely to be applied to a power supply device that supplies power to a motor that drives a group of paper transport rollers.

  The present invention has been made to solve the above problem, and does not require a cooling means such as a temperature sensor for detecting the temperature of the power supply device or a fan for cooling the power supply device, and when a large number of trays are mounted. Thus, an object of the present invention is to provide an image forming apparatus capable of preventing overheating of the power supply apparatus even when a large load is applied to the power supply apparatus.

The invention described in claim 1 includes one or more trays for storing recording media, and forms an image on the recording medium while transporting the recording media stored in the tray along a predetermined transport path. The number of trays for determining whether or not a power supply device for supplying power to the image forming device, one or a plurality of motors fed from the power supply device, and a predetermined number of trays or more are mounted. A motor for driving the motor, comprising: a determining unit; an external temperature determining unit for measuring the device external temperature and determining whether the measured device external temperature is equal to or higher than a predetermined temperature; and a motor drive control unit for controlling the driving of the motor. The control means determines when the tray number determining means determines that a predetermined number or more of trays have been installed and the external temperature determining means determines that the outside air temperature is higher than a predetermined temperature. Performing a motor stop determination operation for stopping a predetermined time the drive to an image forming apparatus according to claim.

  A tray mounted on the image forming apparatus is provided with a conveyance roller that conveys a recording medium such as a recording sheet accommodated therein toward an image forming mechanism for forming an image. Then, by mounting the tray on the image forming apparatus, a recording medium conveyance path is formed by the conveyance roller.

  In an image forming apparatus, one tray is usually mounted as a standard, but an additional tray may be mounted. As the number of trays to be mounted increases, the number of transport rollers also increases. Here, the conveyance rollers are each driven by a motor, and these motors are supplied with power from the power supply device. Therefore, when the number of trays to be mounted increases, the number of motors that drive the transport rollers also increases, so the load on the power supply device also increases. Therefore, when the operation is performed for a long time, the power supply device may be overheated.

  In addition, when the outside air temperature is high, heat is likely to be generated inside the image forming apparatus. Therefore, even when the same load is applied, the power supply device is more likely to be overheated as compared with a low temperature.

  Therefore, in the image forming apparatus, when the predetermined number of trays or more are mounted, the motor is stopped for a certain time on the condition that the outside air temperature is higher than the predetermined temperature, thereby overheating the power supply device. Is preventing. Therefore, in the image forming apparatus, overheating of the power supply apparatus can be prevented without detecting the temperature of the power supply apparatus with the temperature sensor and driving the cooling fan based on the detection result to cool the power supply apparatus.

The invention according to claim 2 includes one or a plurality of trays for storing the recording medium, and forms an image on the recording medium while transporting the recording medium stored in the tray along a predetermined transport path. An image forming apparatus, wherein a double-sided printing unit that forms an image on both sides of the recording medium is detachably formed, a power supply device that supplies power to the image forming device, and one or a plurality of power that is supplied from the power supply device Motor, a tray number determining means for determining whether or not a predetermined number of trays are mounted, a double-sided printing unit detecting means for detecting the presence or absence of the double-sided printing unit, and an apparatus for measuring and measuring the external temperature of the apparatus An external temperature determining means for determining whether or not the external temperature is equal to or higher than a predetermined temperature; and a motor drive control means for controlling the driving of the motor, wherein the motor drive control means has a predetermined number or more. The tray number determining means determines that the double-sided printing unit is installed, the double-sided printing unit detecting means detects that the outside air temperature is higher than a predetermined temperature, and the external The present invention relates to an image forming apparatus that performs a motor stop determination operation to stop the driving of the motor for a certain period of time when a temperature determination unit determines.

  When performing duplex printing on a recording medium, a duplex printing unit is mounted on the image forming apparatus, an image is formed on one side of the recording medium, and then the recording medium is reversed by the duplex printing unit on the other side. Also forms an image. Therefore, the driving time of the transport roller is longer than that when performing single-sided printing. Therefore, when duplex printing is performed, the load on the power supply device increases.

  Therefore, in the image forming apparatus, the motor is stopped for a predetermined time on condition that a predetermined number or more of trays are mounted and a duplex printing unit is mounted and the outside air temperature is higher than the predetermined temperature. As a result, overheating of the power supply device is prevented.

According to a third aspect of the present invention, the motor drive control means performs a motor stop determination operation for stopping the motor drive for a predetermined time when the number of images formed on the recording medium reaches a predetermined value. Alternatively, the present invention relates to the image forming apparatus described in 2.

  In the image forming apparatus, since the number of times the motor is stopped can be reduced, the waiting time of the user can be reduced.

According to a fourth aspect of the present invention, a plurality of toner image forming units that form toner images of different colors are provided, and the toner images formed by the respective toner image forming units are transferred to the recording medium in a superimposed state. Thus, a toner image composed of a plurality of colors is formed, and image quality adjustment for controlling each toner image forming unit is performed at predetermined intervals so that the color balance of the superimposed toner images is within a preset range. 3. The image forming apparatus according to claim 1, wherein the motor drive control unit performs the motor stop determination operation . The invention of claim 5 comprises a plurality of toner image forming means for forming toner images of different colors, and the toner images formed by the respective toner image forming means are transferred to the recording medium in an overlaid state. When a toner image having a plurality of colors is formed and the number of continuous prints, which is the number of images formed on a recording medium in one print job, reaches a first predetermined value, the color balance of the superimposed toner images The image quality adjustment for controlling each toner image forming unit is performed so that is within a preset range, and then the motor drive control unit performs the motor stop determination operation, and the number of continuously printed sheets is the first print number. If the cumulative number of printed sheets, which is the number of recording media delivered from all trays, reaches the second predetermined value, the image quality adjustment is not achieved. Then, when the motor drive control means performs the motor stop determination operation and the cumulative number of printed sheets does not reach the second predetermined value, the image quality adjustment is not performed and the motor drive control is performed. 3. The image forming apparatus according to claim 1, wherein the motor stop determination operation is not performed.

  As described above, a full-color image forming apparatus forms a full-color image by forming toner images of Y, M, C, and K colors and transferring them onto a recording medium. As the number of printed sheets increases, the density of toner images of Y, M, C, and K colors may deviate from the default density, and the color balance may be lost. Therefore, every time a predetermined number of sheets are printed, it is common to perform image quality adjustment to correct the color balance loss by controlling the toner image forming means for each color of Y, M, C, and K.

  In the image forming apparatus, since the motor is stopped after the image quality adjustment, no waiting time is newly generated.

  As described above, according to the present invention, there is no need for a cooling means such as a temperature sensor for detecting the temperature of the power supply device or a fan for cooling the power supply device, and the power supply as in the case where a large number of trays are mounted. An image forming apparatus capable of preventing overheating of the power supply apparatus even when a large load is applied to the apparatus is provided.

1. Embodiment 1

  A full color printer as an example of the image forming apparatus of the present invention will be described below.

  As shown in FIG. 1, the full-color printer 1 includes a main device unit 10 and sheet feeding units 100 </ b> A, 100 </ b> B, and 100 </ b> C mounted in three stages below the main device unit 10. Hereinafter, the paper feeding units 100A, 100B, and 100C may be collectively referred to as “paper feeding unit 100”.

  As shown in FIG. 1, inside the main unit 10, a photosensitive drum 11 on which a toner image is formed, an intermediate transfer belt 15 to which a toner image formed on the photosensitive drum 11 is transferred, And a rotary developing device 14 disposed so as to face the intermediate transfer belt 15 with the photoconductor drum 11 interposed therebetween. The photoreceptor drum 11 and the intermediate transfer belt 15 correspond to the photoreceptor and the intermediate transfer body of the present invention, respectively. An exposure device 13 that exposes the photosensitive drum 11 with the laser beam LB is provided below the rotary developing device 14, and further below that is a tray that accommodates a sheet P that is an example of the recording medium of the present invention. 31 is mounted.

  A photoreceptor layer is formed on the surface of the photoreceptor drum 11. The photosensitive drum 11 rotates in the clockwise direction as indicated by an arrow a in FIG. Around the photosensitive drum 11, a drum cleaning device 20 for cleaning the surface of the photosensitive drum 11 and a downstream side of the drum cleaning device 20 with respect to the rotation direction a of the photosensitive drum 11, the photosensitive drum 11 is provided. And a charging roller 12 for negatively charging the surface. The photosensitive drum 11 is driven by a motor 6A.

  The drum cleaning device 20 includes a cleaning blade 18 that removes toner on the surface of the photosensitive drum 11, and a toner collection container 19 that collects toner removed by the cleaning blade 18.

  The rotary developing device 14 can be rotated in the counterclockwise direction as indicated by an arrow c in FIG. 1, and four developing devices 14Y, 14M, 14C, and 14K are provided along the rotating direction c. Is provided. The developing units 14Y, 14M, 14C, and 14K develop the latent image on the photosensitive drum 1111 with Y toner, M toner, C toner, and K toner, respectively. Each of the developing devices 14Y, 14M, 14C, and 14K includes a developing roller 14a that attaches toner to the surface of the photosensitive drum 11, and a toner cartridge 14b that supplies the toner. The rotary developing device 14 is driven by a motor 6B.

  The intermediate transfer belt 15 is supported by being wound around support rollers 24, 29, 28, and 27, and is wound around the photosensitive drum 11 by the wrap-in roller 21, the primary transfer roller 22, and the wrap-in roller 23. The primary transfer portion is formed. The secondary transfer roller 16 is disposed so as to be able to contact and separate from the intermediate transfer belt 15 relative to the support roller 24. A toner image transfer portion 39 is formed at a portion where the secondary transfer roller 16 contacts the intermediate transfer belt 15. The secondary transfer roller 16 is rotationally driven by a motor 6C.

  The intermediate transfer belt 15 rotates counterclockwise as indicated by an arrow b in FIG. A positive voltage is applied to the primary transfer roller 22.

  A cleaning brush 26 is further disposed around the intermediate transfer belt 15 so as to face the support roller 28. A cleaning blade 25 is disposed above the cleaning brush 26 so as to contact the intermediate transfer belt 15 at the tip. A positive voltage is applied to the cleaning brush 26. The cleaning brush 26 is driven by a motor 6D.

  The fixing device 17 includes a fixing roller 35 and a heating roller 36 disposed so as to face each other across the conveyance path d, and a sheet P on which the toner image is thermally fixed by the fixing roller 35 and the heating roller 36. A feed roller 37 is provided for feeding to the printer.

  In the vicinity of the tray 31, three paper feed rollers 32 for feeding paper are provided. A sheet feeding section 30 is formed by the three sheet feeding rollers 32. The paper feed unit 30 not only sends out the paper P but also has a function of measuring the number of paper P sent out. A pair of transport rollers 33 and three pairs of transport rollers 34 are further provided obliquely above the tray 31. The paper P sent out by the paper feed roller 32 is conveyed toward the image transfer unit 39 along a conveyance path d formed by the conveyance roller 33 and the conveyance roller 34. The paper feed roller 32 and the conveyance roller 33 are driven by a motor 6E. Contact and separation between the paper feed roller 32 and the conveyance roller 33 and the motor 6E are performed by a clutch (not shown).

  The paper feed units 100 </ b> A to 100 </ b> C are also provided with the same tray 31, paper feed roller 32, and transport roller 33 as those provided in the main apparatus unit 10. However, in the paper feed units 100A to 100C, the paper feed roller 32 and the transport roller 33 are driven by the motor 6F. The contact and separation between the paper feed roller 32 and the transport roller 33 and the motor 6F are performed by a clutch (not shown). Also in the paper feed units 100A to 100C, the paper P sent out from the tray 31 by the paper feed roller 32 is sent to the image transfer unit 39 through the transport path d by the transport roller 33 and the transport roller 34.

  As shown in FIG. 2, the main apparatus unit 10 includes a temperature sensor 7 that measures the temperature outside the full-color printer 1, the number of sheets P measured by the sheet feeding unit 30, measurement data from the temperature sensor 7, and main data A CPU 5 that outputs a control designation for controlling the rotation of the motors 6A to 6F based on the number of paper feed units 100 mounted on the apparatus unit 10, and a driver 4A to drive the motors 6A to 6E based on a control command from the CPU 5. 4E and a power supply board 8 that supplies power to the CPU 5, the drivers 4A to 4E, and the paper feeding units 100A to 100C are provided.

  The CPU 5 includes the number of trays discriminating unit 52 that detects whether or not a predetermined number or more of paper feed units 100 are mounted, in other words, whether or not the predetermined number or more of trays 31 are mounted, and the measurement data in the temperature sensor 7. The external temperature determination unit 54 that determines whether or not the external temperature is equal to or higher than a predetermined temperature based on the measurement data and the number of sheets P measured by the paper supply unit 30 are input and The sheet number determination unit 56 that determines whether or not the number of sheets on which an image is formed has reached a predetermined value from the number of sheets, and the determination results in the tray number determination unit 52, the external temperature determination unit 54, and the sheet number determination unit 56 And a motor drive control unit 58 that determines whether to stop the motors 6A to 6F for a predetermined time, for example, 35 seconds. The tray number determination unit 52, the external temperature determination unit 54, and the motor drive control unit 58 correspond to the tray number determination unit, the external temperature determination unit, and the motor drive control unit in the present invention, respectively.

  The sheet feeding units 100A to 100C are input with the number of sheets P to be fed from the sheet feeding unit 30 and a CPU 50 that controls the motor 6F and the sheet feeding unit 30 based on a control command from the CPU 5 in the main apparatus unit 10. And a driver 4F for driving the motor 6F based on a control command from the CPU 50.

  Hereinafter, the operation of the full-color printer 1 will be described.

  As shown in FIG. 5, when printing is started by the full-color printer 1, paper feed is started from the paper feed tray 31 provided in the main apparatus unit 10 or the paper feed units 100A to 100C in step S2. At the same time, the continuous printing number and the cumulative printing number are counted in the paper supply unit 30 included in the main apparatus unit 10 or the paper supply units 100A to 100C (step S4). In step S6, the paper number determination unit 56 of the CPU 5 determines whether or not the continuous print number is equal to or greater than a threshold value. The threshold values for the continuous printing number and the cumulative printing number are set as shown in FIG. The continuous printing number is the number of sheets continuously printed by one print job. In FIG. 7, “toner remaining amount” is the remaining amount of toner in the toner cartridge 14 b in the rotary developing device 14.

  When it is determined in step S6 that the number of continuously printed sheets is equal to or greater than the threshold, a forced process control request is made in the CPU 5 (step S10). Here, the forcible process control request refers to performing process control regardless of whether or not the print job is completed. The process control corresponds to the image quality adjustment of the present invention, and development is performed so that the color balance of the toner image obtained by superimposing the toner images of each color Y, M, C, K is within a preset range. This is a process for controlling the devices 14Y, 14M, 14C, and 14K.

  On the other hand, when it is determined in step S6 that the number of continuous prints is less than the threshold value, the number of sheets P sent out from the sheet feeding tray 31 provided in the main apparatus unit 10 or the sheet feeding units 100A to 100C by the sheet number determination unit 56 It is determined whether or not the accumulated number of printed sheets is equal to or greater than a threshold value (step S8). The “cumulative number of printed sheets” refers to the cumulative number of sheets P on which an image has been formed since the previous process control. If it is determined that the cumulative number of printed sheets is equal to or greater than the threshold, job end process control for performing process control is requested after the currently executing print job ends (step S12).

When a forced process control or job end process control request is made, the paper P is discharged in step S14 (step S14). If it is determined in step S8 that the cumulative number of printed sheets is less than the threshold value, the process immediately proceeds to step S14 without passing through step S12, and the paper P is discharged.
When the paper P is discharged, it is determined again whether or not there has been a process control request (step S16).

  If it is determined in step S16 that a process control request has been made, process control is executed (step S18), and at the same time, an inquiry is made as to whether the remaining amount of toner is less than a predetermined amount (step S20). . On the other hand, when it is determined that there is no process control request, the series of determinations ends at this step, and the procedure starting at step S2 is repeated again.

  When the remaining amount of toner is equal to or greater than the predetermined amount in step 20, the tray number determination unit 52 determines that the number of paper feed units 100 mounted on the main apparatus unit 10, in other words, the number of trays 31 is a predetermined number, for example, four. It is determined whether or not the number is greater than or equal to (step S22). Here, when a large number of paper supply units 100 are mounted, a large number of trays 31 are also mounted, and the number of motors 6F that drive the paper feed rollers 32 and the transport rollers 33 increases. Therefore, since a large load is applied to the power supply board 8, the temperature rise of the power supply board 8 is also large. Therefore, when it is determined in step S22 that the number of the paper feeding units 100 is equal to or greater than the predetermined number, the process proceeds to step S24, and the temperature determination unit 54 determines whether or not the outside air temperature is a predetermined temperature, for example, 30 ° C. or higher. Determination is made (step S24). This is because the temperature rise of the power supply board 8 depends not only on the size of the load but also on the outside air temperature.

  On the other hand, when the number of paper feed units 100 is small or when the paper feed units 100 are not attached, the number of motors 6F to be driven is small or zero, so the load on the power supply board 8 is It is considered that the temperature rise of the power supply substrate 8 is small. Therefore, in this case, the series of determinations ends in step S22, and the procedure starting from step S2 is repeated again.

  When it is determined in step 24 that the outside air temperature is equal to or higher than the predetermined temperature, the motors 6A to 6F are stopped for a predetermined time, for example, 35 seconds, in accordance with a command from the motor drive control unit 58 in step S26. As a result, the load applied to the power supply board 8 is reduced, so that the power supply board 8 is naturally cooled.

  On the other hand, when the outside air temperature is lower than the predetermined temperature, the power supply board 8 is considered to be naturally cooled even if a large load is applied to the power supply board 8, so that the motor is not stopped and the procedure starting with step S2 is performed again. Repeated.

  In the full-color printer 1 according to the first embodiment, under conditions where the power supply substrate 8 is likely to overheat, that is, when a large number of paper feed units 100 are mounted, a large number of trays 31 are mounted and the outside air temperature is high. Then, the motors 6A to 6F are stopped for a predetermined time to naturally cool the power supply substrate 8. Therefore, a temperature sensor for detecting the temperature of the power supply board 8 and a cooling fan for cooling the power supply board 8 are not required. In addition, since the motor is stopped after the process control, it is possible to prevent a new waiting time from being generated by stopping the motor.

2. Embodiment 2
As shown in FIG. 3, the full-color printer 2 according to the second embodiment has a configuration in which a detachable duplex printing unit 102 is loaded on the main apparatus unit 10 of the full-color printer 1 according to the first embodiment.

  The duplex printing unit 102 has a function of reversing the paper P on which the toner image has been fixed by the fixing device 17 and returning it to the transport path d, and a group of reverse transport rollers 40 that transport the paper P in the reverse direction along the transport path e. And a motor 60 for driving the reverse conveying roller 40 and a paper guiding section 42 for guiding the paper P, which is reversely conveyed along the conveying path e, to the conveying path d. As shown in FIG. 4, the duplex printing unit 102 also includes a CPU 51 that outputs a control command to the motor 60 based on a control command from the CPU 5 described later, and a driver that drives the motor 60 based on the control command from the CPU 51. 41.

  The CPU 5 included in the main apparatus unit 10 includes a duplex printing unit detection unit 53 that detects the presence or absence of the duplex printing unit 102 in addition to the tray number determination unit 52, the external temperature determination unit 54, and the motor drive control unit 58. The duplex printing unit detection unit 53 corresponds to the duplex printing unit detection means in the present invention.

  Except for these points, the full-color printer 2 has the same configuration as the full-color printer 1 according to the first embodiment.

  Hereinafter, the operation of the full-color printer 2 will be described.

  In the full color printer 2, as shown in FIG. 6, steps S102 to S126 are sequentially executed. Here, step S102 to step S120 are the same as step S2 to step S20 in the full-color printer 1 of the first embodiment, and a description thereof will be omitted.

  When the remaining amount of toner in step 120 is equal to or greater than the predetermined amount, the tray number determination unit 52 determines that the number of paper feed units 100 mounted on the main apparatus unit 10, in other words, the number of trays 31 is a predetermined number, for example, four. It is determined whether the number is greater than or equal to (step S122).

  If it is determined in step S22 that the number of sheet feeding units 100 is equal to or greater than the predetermined number, in step S23, the duplex unit detection unit 53 detects whether or not the duplex unit 102 is mounted. When the duplex unit 102 is mounted and duplex printing is performed, not only the motors 6A to 6F but also the motor 60 rotates, so that a large load is applied to the power supply board 8. Therefore, if it is determined in step S123 that the number of the sheet feeding units 100 is equal to or greater than the predetermined number, in step S124, the temperature determination unit 54 determines whether the outside air temperature is a predetermined temperature, for example, 30 ° C. or higher. (Step S124). This is because the temperature rise of the power supply board 8 depends not only on the size of the load but also on the outside air temperature. Note that in step S123, instead of directly detecting the duplex unit 102, two batch printable sheets are set in the tray 31 of the main apparatus unit 10 and the paper feed units 100A to 100C. It may be determined that the duplex unit 102 is attached. Here, the two-batch printing means that two toner images are formed on the surface of the photosensitive drum 11 at a time, and two sheets of paper P are continuously conveyed to the front side surface of each sheet P. A printing method in which a toner image is transferred and fixed. According to the two-batch printing, double-sided printing can be performed more efficiently than when paper P is sent out and printed one by one.

  When it is determined in step 124 that the outside air temperature is equal to or higher than the predetermined temperature, in steps S126, the motors 6A to 6F are stopped for a predetermined time, for example, 35 seconds, according to a command from the motor drive control unit 58. As a result, the load applied to the power supply board 8 is reduced, so that the power supply board 8 is naturally cooled.

  On the other hand, when the outside air temperature is lower than the predetermined temperature, the power supply board 8 is considered to be naturally cooled even if a large load is applied to the power supply board 8, so that the motor is not stopped and the procedure starting from step S102 is performed again. Repeated.

  In the full-color printer 2 according to the second embodiment, the power supply board 8 is likely to overheat, that is, when a large number of paper feed units 100 are mounted, a large number of trays 31 are mounted, and the duplex printing unit 102 is mounted. Furthermore, under conditions where the outside air temperature is high, the motors 6A to 6F and the motor 60 are stopped for a certain period of time to naturally cool the power supply board 8. Therefore, a temperature sensor for detecting the temperature of the power supply board 8 and a cooling fan for cooling the power supply board 8 are not required. In addition, since the motor is stopped after the process control, it is possible to prevent a new waiting time from being generated by stopping the motor.

Example 1
In the full-color printer 2 with the three paper feed units 100 and the duplex printing unit 102 attached, the motors 6A to 6F and the motor 60 are stopped for 35 seconds after the process control is completed in the procedure and conditions shown in the flowchart of FIG. When continuously operated under the conditions (Countermeasure A), as shown in FIG. 8, the temperature rise of the T102 transformer, which is a power transformer provided on the power board 8, remained at 85 ° C.

(Example 2)
In the full-color printer 2 according to the second embodiment, in addition to the countermeasure A, the clutch that contacts and separates the paper feed roller 32 and the conveyance roller 33 and the motor 6E or 6F is changed from a high current type (current 0.17A) to a reduced flow type (0. The electromagnetic clutch of 16A) was replaced (Countermeasure B). As a result, as shown in FIG. 8, the temperature rise of the T102 transformer of the power supply substrate 8 remained at 84.5 ° C.

(Comparative Example 1)
When the full-color printer 2 of the second embodiment was operated under the same conditions as those of the first and second embodiments without taking either the countermeasure A or the countermeasure B, the T102 transformer of the power supply board 8 was 87.5 as shown in FIG. It rose to ℃.

FIG. 1 is a schematic cross-sectional view illustrating the overall configuration of the full-color printer according to the first embodiment. FIG. 2 is a block diagram illustrating an electrical configuration of the full-color printer according to the first embodiment. FIG. 3 is a schematic cross-sectional view illustrating the overall configuration of the full-color printer according to the second embodiment. FIG. 4 is a block diagram illustrating an electrical configuration of the full-color printer according to the second embodiment. FIG. 5 is a block diagram illustrating a procedure for determining whether to stop the motor in the full-color printer according to the first embodiment. FIG. 6 is a block diagram illustrating a procedure for determining whether to stop the motor in the full-color printer according to the first embodiment. FIG. 7 is a table showing threshold values for the number of printed sheets when so-called process control (image quality adjustment) is performed. FIG. 8 is a table showing the temperature rise of the power transformer on the power board when the motor is stopped and not performed in the full-color printer according to the first embodiment.

Explanation of symbols

1 Full color printer 2 Full color printer 4 Driver 5 CPU
6A Motor 6B Motor 6C Motor 6D Motor 6E Motor 6F Motor 7 Temperature Sensor 8 Power Supply Board 9 Memory 10 Main Device 11 Photosensitive Drum 12 Charging Roller 13 Exposure Device 14 Rotating Developing Device 14a Developing Roller 14b Toner Cartridge 14Y Developer 14M Developing 14C Developing device 14K Developing device 15 Intermediate transfer belt 16 Secondary transfer roller 17 Fixing device 18 Cleaning blade 19 Toner collection container 20 Drum cleaning device 21 Wrap-in roller 22 Secondary transfer roller 23 Wrap-in roller 24 Support roller 25 Cleaning blade 26 Cleaning brush 28 Support roller 30 Belt cleaning device 31 Tray 32 Paper feed roller 34 Conveyance roller 35 Fixing roller 36 Heating roller 37 Delivery roller 41 Iba 50 CPU
51 CPU
52 Tray Number Discrimination Unit 53 Duplex Printing Unit Detection Unit 54 Temperature Judgment Unit 56 Number of Sheets Determination Unit 60 Motor 100 Paper Feed Unit 100A Paper Feed Unit 100B Paper Feed Unit 100C Paper Feed Unit 102 Duplex Printing Unit

Claims (5)

An image forming apparatus that includes one or a plurality of trays that store recording media, and that forms an image on the recording medium while transporting the recording medium stored in the tray along a predetermined transport path,
A power supply for supplying power to the image forming apparatus;
One or more motors fed from the power supply device;
Tray number discriminating means for discriminating whether or not a predetermined number or more of trays are mounted;
External temperature determination means for measuring the device external temperature and determining whether the measured device external temperature is equal to or higher than a predetermined temperature;
Motor drive control means for controlling the drive of the motor,
The motor drive control means determines that the motor when the tray number determining means determines that a predetermined number or more of trays are mounted and the external temperature determining means determines that the outside air temperature is higher than a predetermined temperature. An image forming apparatus for performing a motor stop determination operation for stopping the driving of the motor for a predetermined time. An image forming apparatus that includes one or a plurality of trays that store recording media, and that forms an image on the recording medium while transporting the recording medium stored in the tray along a predetermined transport path. A duplex printing unit that forms images on both sides of the medium is detachably formed,
A power supply for supplying power to the image forming apparatus;
One or more motors fed from the power supply device;
Tray number discriminating means for discriminating whether or not a predetermined number or more of trays are mounted;
A double-sided printing unit detection means for detecting the presence or absence of the double-sided printing unit;
External temperature determination means for measuring the device external temperature and determining whether the measured device external temperature is equal to or higher than a predetermined temperature;
Motor drive control means for controlling the drive of the motor,
The motor drive control means detects that a predetermined number or more of trays are mounted, the tray number determination means determines that a duplex printing unit is installed, the duplex printing unit detection means detects the outside air temperature, and An image forming apparatus, wherein when the external temperature determining means determines that the temperature is higher than a predetermined temperature, a motor stop determining operation for stopping the driving of the motor for a predetermined time is performed . The image forming apparatus according to claim 1, wherein the motor drive control unit performs the motor stop determination operation when the number of images formed on the recording medium reaches a predetermined value. A plurality of toner image forming units that form toner images of different colors are provided, and the toner images formed by the respective toner image forming units are transferred to the recording medium in a superimposed state, whereby a toner image composed of a plurality of colors And forming
After the image quality adjustment for controlling each toner image forming unit is performed every predetermined period so that the color balance of the superimposed toner images is within a preset range, the motor drive control unit performs the motor stop determination operation. The image forming apparatus according to claim 1 , wherein the image forming apparatus is implemented . A plurality of toner image forming units that form toner images of different colors are provided, and the toner images formed by the respective toner image forming units are transferred to the recording medium in a superimposed state, whereby a toner image composed of a plurality of colors And forming
  When the number of continuous prints, which is the number of images formed on the recording medium in one print job, reaches the first predetermined value, each color is adjusted so that the color balance of the superimposed toner images is within a preset range. The image quality adjustment for controlling the toner image forming unit is performed, and then the motor drive control unit performs the motor stop determination operation,
  When the continuous print number does not reach the first predetermined value, the image quality adjustment is performed when the cumulative print number, which is the number of recording media sent out from all trays, reaches the second predetermined value. Then, the motor drive control means performs the motor stop determination operation,
  When the cumulative number of printed sheets does not reach the second predetermined value, the image quality adjustment is not performed, and the motor drive control unit does not perform the motor stop determination operation.
The image forming apparatus according to claim 1.

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