JP2022052107A - Image forming apparatus - Google Patents

Abstract

To prevent cooling control from being unnecessarily continued in a case in which the cooling control is continued in a state in which a movable body provided with a temperature sensor is located outside a main body housing.SOLUTION: An image forming apparatus comprises: a main body housing; a drawer that holds a cartridge storing developer and can be withdrawn from a position for image formation in the main body housing; a first temperature sensor that is provided in the drawer; and a control unit. The control unit can execute the start and stop of cooling control for cooling the inside of the main body housing on the basis of a temperature for control (TB) based on an acquired value of the first temperature sensor, when the drawer is removed from the position for image formation during the cooling control (S601: Yes), continues the cooling control, and in the state in which the drawer is removed from the position for image formation, when the elapsed time TM from the removal of the drawer from the position for image formation reaches or becomes longer than a predetermined time Tth (S602: Yes), stops the cooling control (S604).SELECTED DRAWING: Figure 8

Description

The present invention relates to an image forming apparatus including a control unit that executes cooling control for cooling the inside of the main body housing.

Conventionally, as a control unit of an image forming apparatus, cooling control is executed when the in-machine temperature acquired by a temperature sensor installed in the main body housing exceeds a predetermined value, and cooling control is stopped when the in-machine temperature falls below a predetermined value. Is known (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2001-075460

By the way, it is conceivable to provide a temperature sensor for acquiring the temperature inside the machine in a drawer that holds the cartridge and can be pulled out from the main body housing. However, in this case, if the drawer is pulled out from the main body housing, the control unit cannot acquire the temperature inside the machine from the temperature sensor. Therefore, when the cooling control is continued while the drawer is being pulled out, the cooling control stop condition is determined. It cannot be done and cooling control may be continued unnecessarily.

Therefore, the present invention is a case where a moving body such as a drawer that can move between the inside of the main body housing and the outside of the main body housing and the cooling control is continued in a state where the moving body provided with the temperature sensor is located outside the main body housing. The purpose is to prevent the cooling control from being unnecessarily continued.

In order to solve the above problems, the image forming apparatus according to the present invention is provided in the main body housing, a drawer that holds a cartridge for accommodating the developer and can be pulled out from the image forming position of the main body housing, and the drawer. The first temperature sensor and the control unit are provided.
The control unit can start and stop the cooling control for cooling the inside of the main body housing based on the control temperature based on the acquired value of the first temperature sensor, and the drawer can be executed during the cooling control. Is removed from the image forming position, the cooling control is continued, and the drawer is removed from the image forming position in a state where the drawer is removed from the image forming position. When the time exceeds a predetermined time, the cooling control is stopped.

According to this configuration, even if the drawer is removed from the image forming position and the acquired value cannot be acquired from the first temperature sensor, the cooling control is stopped when the elapsed time exceeds a predetermined time, so that cooling is performed. It is possible to prevent the control from being continued unnecessarily. If the elapsed time is longer than a predetermined time, it is highly possible that the cartridge is exposed to the outside air for a long time and is sufficiently cooled, so that there is no problem even if the cooling control is stopped.

Further, when the drawer is moved to the image forming position and the elapsed time is less than the predetermined time, the control unit stops the cooling control based on the control temperature. May be good.

According to this configuration, if the drawer is moved to the image forming position when the elapsed time is less than a predetermined time, the cooling control is stopped based on the control temperature, so that the cooling is performed based on the appropriate control temperature. Control can be stopped.

Further, the image forming apparatus may include a fan for cooling the inside of the main body housing, and the control unit may increase the air volume of the fan in the cooling control as compared with the case where the cooling control is not executed. ..

According to this configuration, the inside of the main body housing can be cooled by blowing air from the fan.

Further, the control unit may calculate the control temperature based on the acquired value of the first temperature sensor and the operating amount of the cartridge.

According to this configuration, the control temperature can be calculated accurately.

Further, the drawer is provided with a first contact conducting with the first temperature sensor, the main body housing is provided with a second contact conducting with the control unit, and the drawer is disengaged from the image forming position. When the first contact is separated from the second contact and the drawer is arranged at the image forming position, the first contact may be configured to be connected to the second contact.

According to this configuration, the control unit can determine that the drawer is out of the image forming position when no response can be obtained from the first temperature sensor.

Further, the image forming apparatus includes a second temperature sensor that acquires the outside air temperature, and the control unit has an acquisition value of the first temperature sensor, an operating amount of the cartridge, and an acquisition value of the second temperature sensor. The control temperature may be calculated based on the above.

According to this configuration, the calculation of the control temperature can be performed more accurately.

Further, the cartridge may include a developing roller and an accommodating portion for accommodating a developing agent.

Further, the drawer may include a photoconductor.

Further, the first temperature sensor may be provided on the upstream side of the cartridge in the drawer drawing direction of the drawer.

By providing the first temperature sensor on the upstream side of the cartridge in the drawer drawing direction, the temperature of the first temperature sensor becomes higher in the main body housing when the drawer is arranged at the image forming position of the main body housing. Since it is arranged near the center where it is easy to operate, the control temperature can be appropriately calculated based on the temperature of the portion of the main body housing where the temperature tends to be high, and appropriate cooling control can be performed.

Further, the image forming apparatus may include a fixing device for fixing the developer image on the sheet, and the first temperature sensor may be provided at a position between the cartridge and the fixing device.

According to this configuration, the first temperature sensor can measure the heat transferred from the fixing device toward the cartridge.

Further, the image forming apparatus according to the present invention includes a main body housing, a cartridge that can be attached to and detached from the main body housing and contains a developer, a first temperature sensor provided in the cartridge, a control unit, and the like. To prepare for.
The control unit can start and stop the cooling control for cooling the inside of the main body housing based on the control temperature based on the acquired value of the first temperature sensor, and the cartridge can be executed during the cooling control. Is taken out from the main body housing, the cooling control is continued, and in a state where the cartridge is taken out from the main body housing, the elapsed time from the cartridge being taken out from the main body housing is predetermined. When the time is exceeded, the cooling control is stopped.

According to this configuration, even if the cartridge is taken out from the main body housing and the acquired value cannot be acquired from the first temperature sensor, the cooling control is stopped when the elapsed time exceeds a predetermined time, so that the cooling control is performed. Can be prevented from being continued in vain. If the elapsed time is longer than a predetermined time, it is highly possible that the cartridge is exposed to the outside air for a long time and is sufficiently cooled, so that there is no problem even if the cooling control is stopped.

According to the present invention, when the cooling control is continued in a state where the moving body provided with the temperature sensor is located outside the main body housing, it is possible to prevent the cooling control from being unnecessarily continued.

It is a figure which shows the structure of a color printer. It is a figure which shows the state which pulled out a drawer. It is a figure explaining the state of separation / contact between a photosensitive drum and a developing roller. It is a thermal circuit that shows the heat in and out of the layer thickness regulation blade. It is a flowchart which shows the operation of a control part. It is a flowchart which shows the 1st temperature calculation process. It is a flowchart which shows the cooling control start end determination. It is a flowchart which shows the process at the time of opening a cover. It is a flowchart which shows the 2nd temperature calculation process. It is a figure which shows the modification which the cartridge was provided with the 1st temperature sensor.

Next, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, a color printer 1 as an example of an image forming apparatus includes a main body housing 10, a paper feeding unit 20 for supplying a sheet P, and an image forming unit for forming an image on the fed sheet P. 30 is provided, a transport unit 90 for discharging the sheet P on which the image is formed, and a control unit 100.

The main body housing 10 has a first opening 10A, a front cover 11, a second opening 10B, and a rear cover 12. The first opening 10A is an opening through which the unit U described later can pass. The front cover 11 is rotatable between an open position for opening the first opening 10A and a closed position for closing the first opening 10A.

The second opening 10B is an opening through which the sheet P can pass. The rear cover 12 is rotatable between an open position for opening the second opening 10B and a closed position for closing the second opening 10B.

The paper feed unit 20 includes a paper feed tray 21 for accommodating the sheet P, and a sheet transfer mechanism 22 for transporting the sheet P from the paper feed tray 21 to the image forming unit 30.

The image forming unit 30 includes a scanner unit 40, a unit U, a transfer unit 70, and a fixing device 80.

The scanner unit 40 includes a laser emitting unit (not shown), a polygon mirror, a lens, a reflecting mirror, and the like. The scanner unit 40 irradiates the surface of each photosensitive drum 61 with a laser beam.

The unit U can be pulled out from the main body housing 10 through the first opening 10A. The unit U includes four cartridges 50 and a drawer 60.

The cartridge 50 is removable from the drawer 60. The cartridge 50 includes an accommodating portion 51 for accommodating toner as an example of a developer, a developing roller 52, and a layer thickness regulating blade 53 that comes into contact with the developing roller 52 and regulates the layer thickness of toner on the developing roller 52. I have. Toners of each color of yellow, magenta, cyan, and black are accommodated in the accommodating portion 51 of the four cartridges 50.

The cartridges 50 are arranged in this order from the upstream of the sheet P in the transport direction, which are represented by the codes of 50Y, 50M, 50C, and 50K containing toners of each color of yellow, magenta, cyan, and black. In the present specification and the drawings, when the photosensitive drum 61, the developing roller 52, etc. corresponding to the toner color are specified, the Y, M, C, etc. correspond to each of yellow, magenta, cyan, and black. The symbol K will be added.

In a state where the unit U is arranged at the image forming position of the main body housing 10, the cartridge 50Y is located closest to the first opening 10A, and the cartridge 50K is located farthest from the first opening 10A. In the following description, the cartridge 50K is also referred to as a "first cartridge 50K", and the cartridge 50Y is also referred to as a "second cartridge 50Y". The first cartridge 50K is closer to the fixing device 80 than the second cartridge 50Y.

The drawer 60 can be pulled out in a direction orthogonal to the vertical direction from the image forming position of the main body housing 10. Here, the image forming position refers to the position of the drawer 60 when forming an image. The drawer 60 includes a photosensitive drum 61 as an example of a photoconductor, a charger (not shown), a frame 62 for detachably holding four cartridges 50, a first temperature sensor SE1, and a first contact CN1. ing. The photosensitive drum 61 and the charger are provided on the frame 62 in four corresponding to the four developing rollers 52.

The frame 62 is movably supported by the main body housing 10 in a direction orthogonal to the vertical direction. The first temperature sensor SE1 is, for example, a thermistor, and acquires the temperature inside the machine, which is the temperature inside the main body housing 10. The first contact CN1 is conducting with the first temperature sensor SE1 via wiring.

The first temperature sensor SE1 and the first contact CN1 are provided on the upstream side of the first cartridge 50K on the most upstream side in the drawer direction D of the drawer 60. In other words, the first temperature sensor SE1 and the first contact CN1 are provided at positions between the most upstream first cartridge 50K and the fixing device 80 in the drawer direction D of the drawer 60. The distance from the first temperature sensor SE1 to the first cartridge 50K is smaller than the distance from the first temperature sensor SE1 to the second cartridge 50Y.

The main body housing 10 includes a second contact CN2 that conducts with the control unit 100 via wiring. The first contact CN1 is connected to the second contact CN2 in a state where the drawer 60 is arranged at the image forming position of the main body housing 10. Specifically, when the drawer 60 is arranged at the image forming position, the first contact CN1 is connected to the second contact CN2.

Further, as shown in FIG. 2, when the drawer 60 is pulled out from the main body housing 10, the first contact CN1 is separated from the second contact CN2. Specifically, when the drawer 60 deviates from the image forming position, the first contact CN1 separates from the second contact CN2.

Returning to FIG. 1, the transfer unit 70 includes a drive roller 71, a driven roller 72, a transfer belt 73, and a transfer roller 74. The conveyor belt 73 is an endless belt. The drive roller 71 and the driven roller 72 are rollers that rotate the conveyor belt 73. The transfer rollers 74 are rollers that sandwich the transport belt 73 with the corresponding photosensitive drum 61, and four transfer rollers 74 are arranged so as to face each photosensitive drum 61.

The fixing device 80 is a device for fixing a toner image on the sheet P. The fixing device 80 includes a heating roller 81 heated by the heater H and a pressure roller 82 pressed by the heating roller 81.

When the drawer 60 is in the image forming position of the main body housing 10, the color printer 1 can form an image. The image forming position is a position where the photosensitive drum 61 and the transfer unit 70 are in contact with each other, and the scanner unit 40 is a position where a predetermined position of the photosensitive drum 61 can be exposed. In the image forming unit 30, first, the surface of each photosensitive drum 61 is uniformly charged by the charging device, and then exposed by the scanner unit 40. As a result, an electrostatic latent image based on the image data is formed on each photosensitive drum 61. After that, the toner in the accommodating portion 51 is supplied to the electrostatic latent image on the photosensitive drum 61 by the developing roller 52, so that the toner image is formed on the photosensitive drum 61.

Next, the sheet P supplied on the transport belt 73 passes between each photosensitive drum 61 and each transfer roller 74, so that the toner image formed on each photosensitive drum 61 is transferred onto the sheet P. Toner. Then, as the sheet P passes between the heating roller 81 and the pressure roller 82, the toner image transferred onto the sheet P is heat-fixed.

The transport unit 90 functions as a discharge mechanism for discharging the sheet P carried out from the image forming unit 30 to the discharge tray 13 of the main body housing 10, and the sheet P having an image formed on one surface by the image forming unit 30. It functions as a re-transporting means for re-transporting the sheet P to the image forming unit 30 in a state where the front and back sides of the sheet P are inverted. Specifically, the transport unit 90 mainly includes a transport path 91, a discharge roller 92, and a re-transport path 93.

The transport path 91 is a path that guides the sheet P from the fixing device 80 toward the discharge tray 13.

The discharge roller 92 is configured to be rotatable in both forward and reverse directions, and discharges the sheet P carried out from the image forming unit 30 toward the discharge tray 13 during forward rotation, and discharges the sheet P toward the discharge tray 13 during reverse rotation. Transport so that it is pulled in.

The re-conveyance path 93 is configured to guide the sheet P on which an image is formed on one surface by the image forming unit 30 to the image forming unit 30 again by passing under the paper feeding unit 20.

When the image formation is completed in the transfer unit 90, the sheet P carried out from the image forming unit 30 is conveyed along the transfer path 91 and discharged to the outside of the main body housing 10 by the forward-rotating discharge roller 92. It is placed on the discharge tray 13. Further, when an image is formed on the other surface of the sheet P on which the image is formed on one surface, the discharge roller 92 is reversed before the entire sheet P is completely discharged to the outside of the main body housing 10. By rotating, the sheet P is pulled back into the main body housing 10 again, and is transported from the transport path 91 to the re-transport path 93. After that, the sheet P is conveyed through the re-conveyance path 93, and is again conveyed to the image forming unit 30 by the paper feeding unit 20.

The main body housing 10 has a fan 14, an intake port 15, and a second temperature sensor SE2.

The fan 14 is a fan that cools the inside of the main body housing 10, and is arranged above the fixing device 80. The fan 14 is arranged between the fixing device 80 and the drawer 60. The fan 14 is configured to suck the air inside the main body housing 10 and discharge it to the outside.

The intake port 15 is an opening for taking in air into the main body housing 10 from the outside. The intake port 15 is arranged on the side opposite to the drawer 60 with respect to the fixing device 80. The intake port 15 is arranged below the fixing device 80. That is, the intake port 15 is arranged at a position that is not easily affected by the heat generated by the fixing device 80 and the cartridge 50.

The second temperature sensor SE2 is, for example, a thermistor, and is arranged facing the inside of the intake port 15. The second temperature sensor SE2 is configured to acquire the outside air temperature, which is the temperature outside the main body housing 10, by detecting the temperature of the air taken in from the intake port 15. The second temperature sensor SE2 is connected to the control unit 100 via wiring.

Further, the color printer 1 further includes a front cover opening / closing sensor 11A for detecting the opening / closing of the front cover 11 and a rear cover opening / closing sensor 12A for detecting the opening / closing of the rear cover 12.

When the front cover open / close sensor 11A and the rear cover open / close sensor 12A are closed, a part of the covers 11 and 12 hits and outputs an ON signal to the control unit 100. The front cover open / close sensor 11A and the rear cover open / close sensor 12A output an OFF signal to the control unit 100 when the covers 11 and 12 are separated from each other when the covers 11 and 12 are open.

The control unit 100 has a CPU, ROM, RAM, and the like, and is configured to execute various processes in response to reception of a print command or the like according to a program or the like prepared in advance. As shown in FIG. 3, the control unit 100 can execute a color mode for forming a multicolored image, a monochrome mode for forming a monochromatic image, and a total separation mode. The control unit 100 switches each mode by controlling the separation mechanism 200 for contacting or separating the developing roller 52 with respect to the photosensitive drum 61.

Specifically, in the color mode, the control unit 100 brings all the developing rollers 52Y, 52M, 52C, 52K into contact with the corresponding photosensitive drums 61Y, 61M, 61C, 61K, and causes all the developing rollers 52 to come into contact with each other. All photosensitive drums 61 are rotated. That is, the control unit 100 operates all the cartridges 50 including the first cartridge 50K and the second cartridge 50Y when forming a multicolored image.

In the monochrome mode, the control unit 100 brings only the black developing roller 52K into contact with the photosensitive drum 61K, and the other three-color developing rollers 52Y, 52M, 52C are from the corresponding photosensitive drums 61Y, 61M, 61C. Separate. Further, in the monochrome mode, the control unit 100 rotates only the developing roller 52K and all the photosensitive drums 61, and stops the other developing rollers 52Y, 52M, 52C. That is, when forming a monochromatic image, the control unit 100 operates the first cartridge 50K without operating the color cartridges 50Y, 50M, 50C including the second cartridge 50Y.

Further, when cleaning the photosensitive drum 61, for example, the control unit 100 executes the total separation mode to make all the developing rollers 52Y, 52M, 52C, 52K, and the corresponding photosensitive drums 61Y, 61M, respectively. Separate from 61C and 61K.

The control unit 100 can execute cooling control for cooling the inside of the main body housing 10 based on the control temperature. Here, the control temperature is a temperature estimated as the temperature of the cartridge 50, and in the present embodiment, it is estimated as the temperature _TB of the layer thickness regulating blade 53.

The control unit 100 is configured to calculate the first control temperature corresponding to the first cartridge 50K and to calculate the second control temperature corresponding to the second cartridge 50Y. Then, the control unit 100 executes the cooling control based on the higher of the first control temperature and the second control temperature.

Specifically, the control unit 100 is a temperature change of the layer thickness regulating blade 53 from the previous calculation to the present at predetermined time intervals based on the inside temperature, the outside air temperature, the driving state of the developing roller 52, and the like. The difference temperature is calculated, and the sum of the obtained difference temperature and the temperature of the layer thickness regulating blade 53 calculated last time is calculated as the current temperature of the layer thickness regulating blade 53.

Specifically, the temperature TB (n) [° C.] of the current layer thickness regulating blade 53 is the temperature _TB (n _- 1) [° C.] of the layer thickness regulating blade 53 calculated last time, and the layer thickness regulating blade. Using the differential temperature ΔTB [° _C ] of 53,
_TB (n) = _TB (n _- 1) + ΔTB ... (1)
It is obtained by the calculation.

Here, as shown in FIG. 4, the difference temperature _ΔTB [° C.] of the layer thickness regulating blade 53 in the equation (1) moves from the air inside the machine, specifically around the first temperature sensor SE1, to the layer thickness regulating blade 53. The amount of heat ΔE _in—B (n) [J] to be generated, the amount of heat ΔE _{out-B (} n) [J] transferred from the layer thickness regulating blade 53 to the outside air, and the calorific value QB [W] of the layer thickness regulating blade 53. Using,
_ΔTB
= (ΔE _in-B (n) -ΔE _{out-B (} n) + QB x Δt) / _CB ... (2)
However,
CB [J / ° _C ] Heat capacity of layer thickness regulation blade Δt [s] Obtained by the calculation of the time from the previous calculation to the present.

The amount of heat ΔE _{in −B} (n) [J] transferred from the air inside the machine to the layer thickness regulating blade 53 _in the equation (2) is the previously acquired inside temperature Tin (n-1) [° C.] and the previous time. Using the calculated temperature _TB (n-1) [° C.] of the layer thickness regulating blade 53 and the thermal resistance R _in-B [° C./W] between the air inside the machine and the layer thickness regulating blade 53,
ΔE _in-B (n)
= (T _in (n-1) _-TB (n-1)) × Δt / R _in-B ... (3)
It is obtained by the calculation.

Further, the amount of heat ΔE _out-B (n) [J] transferred from the layer thickness regulating blade 53 in the equation (2) to the outside air was calculated last time as the previously acquired outside air temperature T _out (n-1) [° C.]. Using the temperature _TB (n-1) [° C.] of the layer thickness regulating blade 53 and the thermal resistance R _out-B [° C./W] between the outside air temperature and the layer thickness regulating blade 53,
ΔE _out-B (n)
= ( _TB (n-1) -T _out (n-1)) x Δt / R _out-B ... (4)
It is obtained by the calculation.

R _in-B and R _out-B in the equations (3) and (4) are set to different values when the first control temperature is calculated and when the second control temperature is calculated. .. In other words, the first function used for the calculation of the first control temperature and the second function used for the calculation of the second control temperature are different in R _in-B and R _out-B .

Specifically, since the distance from the first temperature sensor SE1 to the first cartridge 50K and the distance from the first temperature sensor SE1 to the second cartridge 50Y are different, the in-flight temperature T as the acquired value of the previous first temperature sensor SE1. 1 / R _in-B , which is a coefficient to be applied to _in (n-1) and the like, is set to a different value between the first function and the second function. Here, 1 / R _{in-B in} the first function corresponds to the first coefficient, and 1 / R _{in-B in} the second function corresponds to the second coefficient.

Further, since the distance from the predetermined position outside the main body housing 10 to the first cartridge 50K and the distance from the predetermined position outside the main body housing 10 to the second cartridge 50Y are different, the previously acquired value of the second temperature sensor SE2. 1 / R _out-B , which is a coefficient to be applied to the outside air temperature To _out (n-1), is set to a different value between the first function and the second function. Here, 1 / R _out-B in the first function corresponds to the third coefficient, and 1 / R _out-B in the second function corresponds to the fourth coefficient.

Further, the _calorific value QB of the layer thickness regulating blade 53 in the equation (2) is a parameter that changes according to the operating amount of the cartridge 50, and corresponds to the operating amount of the cartridge 50. The _calorific value QB can be set, for example, based on the drive time, stop time, and rotation speed of the developing roller 52.

From the equations (2) to (4), the control unit 100 has the _in -flight temperature Tin (n-1) which is the acquired value of the first temperature sensor SE1 last time, the first coefficient 1 / R _in-B , and the last time. Acquisition of the temperature _TB (n-1) of the previous layer thickness regulation blade 53K, which is the temperature for the first control, the calorific value QB, which is the operating amount of the first cartridge _50K , and the previous second temperature sensor SE2. Based on the outside air temperature To _out (n-1), which is a value, and the third coefficient 1 / R _{out-B ,} the temperature TB of the layer thickness regulating blade 53K, which is the first control temperature, is calculated.

Further, the control unit 100 has an _in -flight temperature Tin (n-1) which is the acquired value of the first first temperature sensor SE1 of the previous time, a second coefficient 1 / R _in-B , and a temperature for the first control of the previous time. The temperature _TB (n-1) of the previous layer thickness regulation blade _53Y , the calorific value QB which is the operating amount of the second cartridge 50Y, and the outside air temperature To _out which is the acquired value of the previous second temperature sensor SE2 ( Based on n-1) and the fourth coefficient 1 / R _{out-B ,} the temperature TB of the layer thickness regulating blade 53Y, which is the second control temperature, is calculated.

The control unit 100 describes each of the drive state of the developing roller 52, the open / closed state of the rear cover 12, the size of the sheet P, the drive state of the fan 14, and the state of the fixing device 80 when performing single-sided printing and double-sided printing. The above constants (QB, _CB , R _{in-B ,} R _out-B ) are acquired from the storage unit according to each of the states, and the temperature of the layer thickness regulating blade 53 is calculated using the acquired constants. .. Here, the storage unit is, for example, a ROM or RAM, and stores, for example, a map showing the relationship between a plurality of combinations of each state and a plurality of constants. For example, a predetermined value is set as the above-mentioned constant for the closed state of the rear cover 12, and when the rear cover 12 is in the open state, the values of R _in-B and R _out-B among the above-mentioned constants are set. Is set to a value different from the predetermined value.

Here, in the present embodiment, the driving state of the developing roller 52 is a state corresponding to the driving / stopping of the motor for driving the developing roller 52 and the rotation speed of the developing roller 52. The fixing device 80 includes a printing state, a ready state in which the temperature is maintained lower than that at the time of printing, and a sleeping state in which the fixing device 80 is OFF.

In principle, the control unit 100 obtains the first control temperature and the second control temperature by calculation using the first function and the second function described above. However, depending on the situation, the control unit 100 sets the first control temperature and the second control temperature without using the first function and the second function, as an exception.

Further, the control unit 100 starts / ends the cooling control based on the first control temperature and the second control temperature in principle. However, depending on the situation, the control unit 100 exceptionally terminates the cooling control without being based on the first control temperature and the second control temperature.

Further, the control unit 100 is configured to continue the cooling control when the drawer 60 is removed from the image forming position during the cooling control.

Hereinafter, the operation of the control unit 100 will be described in detail. The control unit 100 repeatedly executes the process shown in FIG.

In the process shown in FIG. 5, the control unit 100 first executes the first temperature calculation process (S1). As shown in FIG. 6, in the first temperature calculation process, the control unit 100 first acquires the inside temperature and the outside air temperature from the temperature sensors SE1 and SE2, and uses them for the first function and the second function from the storage unit. Each constant (Q _B , CB, R _{in-B ,} R _out-B ) is acquired (S101). Specifically, in step S101, the control unit 100 determines each state such as the driving state of each developing roller 52 in the first cartridge 50K and the second cartridge 50Y, and based on each determined state, the first function and Acquire each constant (QB, _CB , R _{in-B ,} R _out-B ) used for the second function.

After step S101, the control unit 100 calculates the temperature _TB (n) of the layer thickness regulating blade 53K, which is the first control temperature, based on the first function, and the second control temperature is calculated based on the second function. The temperature _TB (n) of the layer thickness regulating blade 53Y is calculated (S102). Specifically, in step S102, the control unit 100 uses the temperature TBs of the layer thickness regulating blades 53K and 53Y stored _in the storage unit, the internal temperature Tin, and the outside air temperature _{T out} as the first function. And the operation is performed by substituting the TB (n-1) of the second function and the _Tin (n-1) and the _{T out} (n-1), respectively.

The _TB , Tin, and To out when the calculation in step S102 is first performed in the color printer 1 may be stored in the storage unit _in advance as initial values, and the _TB , _{Tin, and To out may} be stored _in the storage unit in advance. , Each may be set based on the in-flight temperature and the outside air temperature acquired this time.

After step S102, the control unit 100 transfers the temperature TB (n) of the layer thickness regulating blades 53K and 53Y calculated this time, the _in -flight temperature Tin (n) and the outside air temperature _{T out} (n) acquired this time. By overwriting the _TB , Tin, and To _{out in} the storage unit, the _TB , _Tin , and To _out are updated (S103), and the first temperature calculation process is terminated. _In this embodiment, _TB , Tin, and To _out are overwritten, but _TB , Tin, and To _out may be stored _in predetermined numbers in chronological order.

Returning to FIG. 5, the control unit 100 executes the cooling control start / end determination after step S1 (S2). As shown in FIG. 7, in the cooling control start / end determination, the control unit 100 first determines the temperature TB of the layer thickness regulating blade 53K of the first cartridge 50K and the temperature T of the layer thickness regulating blade _53Y of the second cartridge 50Y. _B is acquired from the storage unit (S201). After step S201, the higher temperature _TB of the temperature TB of the layer thickness regulating blade 53K and the temperature _TB of the layer thickness regulating blade _53Y is selected (S202).

After step S202, the control unit 100 determines whether or not the temperature _TB is equal to or less than the first threshold value T1 (S203). If it is determined in step S203 that _TB ≤ T1 is not (No), the control unit 100 determines whether or not the temperature _TB is greater than the first threshold value T1 and equal to or less than the second threshold value T2 (S204). ).

Here, the second threshold value T2 is a temperature equal to or lower than the melting point of the toner. The second threshold value T2 may have the same value as the first threshold value T1.

If it is determined in step S204 that _TB ≤ T2, that is, the temperature _TB is larger than the second threshold value T2 (No), the control unit 100 starts cooling control (S206) and ends this process. do. If the process of step S206 is started during the cooling control, the control unit 100 continues the cooling control. If it is determined to be Yes in step S203 or step S204, the control unit 100 ends the cooling control (S205) and ends this process.

The control unit 100 executes the following processing based on the temperature _TB during the cooling control. During the cooling control, the control unit 100 increases the air volume of the fan 14 when the temperature _TB is larger than the second threshold value T2 and is equal to or lower than the third threshold value T3, as compared with the case where the cooling control is not executed. Specifically, in the cooling control, the control unit 100 rotates the fan 14 at a rotation speed higher than the rotation speed of the fan 14 before starting the cooling control.

Further, in the cooling control, when the temperature _TB is larger than the third threshold value T3 and larger than the third threshold value T3 and is equal to or lower than the fourth threshold value T4, the control unit 100 has a unit time in the print control. The number of printed pages per hit is reduced compared to when the cooling control is not executed. As a method of reducing the number of printed pages, for example, the rotation speed of the photosensitive drum 61, the developing roller 52, etc. is lowered as compared with the case of performing normal printing, and the conveying speed of the sheet P is made slower than that of normal printing. A method of making the sheet P, a method of making the transfer interval of the sheet P larger than that in the case of normal printing, and the like can be mentioned. In normal printing, the printing control is performed before the cooling control is started, and the printing control is executed so that the number of printed pages per unit time is maximized.

In the method of slowing down the transfer speed of the sheet P, the rotation speed of the developing roller 52 is reduced, so that heat generation due to friction between the developing roller 52 and the layer thickness regulating blade 53 can be suppressed and the cartridge 50 can be cooled. can. In this case, as an example, the transport speed of the sheet P can be halved when the cooling control is not executed. Further, in the method of increasing the transfer interval of the sheet P, the frequency in which the sheet P that takes heat from the heating roller 81 is supplied to the fixing device 80 is reduced, the amount of heat generated from the fixing device 80 is suppressed, and the in-machine temperature T. The cartridge 50 can be cooled by suppressing the increase _{in in} .

Further, the control unit 100 stops printing when the temperature _TB is larger than the fourth threshold value T4 during the cooling control. By stopping printing, it is possible to suppress the generation of heat due to friction between the developing roller 52 and the layer thickness regulating blade 53 and the amount of heat generated from the fixing device 80, so that the cartridge 50 can be cooled.

Returning to FIG. 5, the control unit 100 determines whether or not there is a print job after step S2 (S3). If it is determined in step S3 that there is a print job (Yes), the control unit 100 executes the print process based on the print job (S4). After step S4 or when it is determined as No in step S3, the control unit 100 determines whether or not the front cover 11 is open based on the signal from the front cover open / close sensor 11A (S5).

If it is determined in step S5 that the front cover 11 is not open (No), the control unit 100 returns to the process of step S1. If it is determined in step S5 that the front cover 11 is open (Yes), the control unit 100 executes the cover opening process (S6), and then returns to the process of step S1.

As shown in FIG. 8, in the cover opening process, the control unit 100 first receives a response from the first temperature sensor SE1 provided in the drawer 60, that is, the first contact CN1 is separated from the second contact CN2. By determining whether or not the drawer 60 is pulled out from the image forming position of the main body housing 10 (S601). When it is determined in step S601 that the drawer 60 is pulled out from the image forming position of the main body housing 10 (Yes), the control unit 100 determines the elapsed time TM after the drawer 60 is pulled out from the image forming position. It is determined whether or not it is Tth or more for a predetermined time (S602).

If it is determined in step S602 that TM ≧ Tth is not (No), the control unit 100 executes the second temperature calculation process (S603). As shown in FIG. 9, the second temperature calculation process includes steps S111 and S113, which are partially different from the above-mentioned steps S101 and S103 of the first temperature calculation process, and the same steps as the above-mentioned first temperature calculation process. This is a process having S102.

In step S111, the control unit 100 acquires the outside air temperature from the second temperature sensor SE2 and uses the constants (QB, _CB , R _{in-B ,} R) for the first function and the second function from the storage unit. _out-B ) is acquired, but the in-flight temperature is not acquired from the first temperature sensor SE1. The control unit 100 executes step S102 after step S111, and then proceeds to step S113.

In step S113, the control unit 100 overwrites the temperature TB (n) of the layer thickness regulating blades 53K and 53Y calculated this time and the outside air temperature _{T out} (n) acquired this time on the _TB and T _out in the storage unit. By doing so, _TB and To _out are updated, but the in-flight temperature Tin _in the storage unit is not updated. As a result, the in-flight temperature Tin _in the storage unit is maintained at the acquired value of the first temperature sensor SE1 acquired by the control unit 100 immediately before the drawer 60 is removed from the image forming position. Therefore, if the control unit 100 determines in step S601 that the drawer 60 has been pulled out from the image forming position (Yes), the control unit 100 has acquired the first drawer 60 immediately before being pulled out from the image forming position in step S102. Based on the acquired value of the temperature sensor SE1 and the temperature TB of the previous layer thickness regulating blades 53K and _53Y , the temperature _TB (n) of the current layer thickness regulating blades 53K and 53Y is calculated.

Returning to FIG. 8, when it is determined in step S602 that TM ≧ Tth (Yes), the control unit 100 stops the cooling control regardless of the temperature _TB of the layer thickness regulating blades 53K and 53Y (Yes). S604). That is, the control unit 100 controls the cooling when the elapsed time TM after the drawer 60 is removed from the image forming position becomes Tth or more for a predetermined time in the state where the drawer 60 is removed from the image forming position. To stop.

After step S603 or step S604, the control unit 100 determines whether there is a response from the first temperature sensor SE1, that is, whether the first contact CN1 is connected to the second contact CN2, so that the drawer 60 is the main body housing. It is determined whether or not the image is arranged at the image forming position of 10 (S605). If it is determined in step S605 that the drawer 60 is not arranged at the image forming position (No), the control unit 100 returns to the process of step S602.

When it is determined in step S605 that the drawer 60 is arranged at the image forming position (Yes), the control unit 100 replaces at least one of the first cartridge 50K and the second cartridge 50Y, which are the targets of the temperature calculation, with new ones. It is determined whether or not it has been done (S606). Here, the determination as to whether or not the cartridge has been replaced with a new one may be made based on, for example, the information stored in the IC chip provided in the cartridge 50, or the cartridge 50 may be moved from the new position to the old position. The determination may be made by detecting the position of a possible protrusion.

If it is determined in step S606 that the product has been replaced with a new one (Yes), the control unit 100 rewrites the temperature _TB in the storage unit corresponding to the new cartridge 50 to the outside air temperature To _out (n) acquired this time (yes). S607). That is, when the control unit 100 determines that the drawer 60 has been replaced with a new one (S606: Yes) when the drawer 60 is moved to the image forming position (S605: Yes), the control unit 100 is concerned with the elapsed time TM. Instead of using each temperature _TB in the storage unit as the previous first control temperature and second control temperature, the first control temperature and the second control temperature are based on the acquired values of the second temperature sensor SE2. The temperature _TB in the storage unit as the temperature is set. If it is determined in step S606 that both the first cartridge 50K and the second cartridge 50Y have not been replaced with new ones (No), the control unit 100 has elapsed since the drawer 60 was pulled out from the image forming position. It is determined whether or not the time TM is equal to or longer than the predetermined time Tth (S608).

If it is determined in step S608 that TM ≧ Tth is not (No), the control unit 100 executes the first temperature calculation process shown in FIG. 6 (S609). That is, in the control unit 100, after the drawer 60 is pulled out from the image forming position (S601: Yes), when the drawer 60 is moved to the image forming position (S605: Yes), the drawer 60 is used for image forming. When the elapsed time TM after being pulled out from the position is less than the predetermined time Tth (S608: No), the previous acquisition value (Tin) of the first temperature sensor SE1 stored _in the storage unit is used. The temperature _TB (n) of the current layer thickness regulating blades 53K and 53Y is calculated based on the temperature _TB and the like of the previous layer thickness regulating blades 53K and 53Y.

In the first temperature calculation process immediately after it is determined in step S605 that the drawer 60 is placed at the image forming position, the drawer 60 is set from the image forming position as the previous _in -flight temperature Tin (n-1). The Tin _in the storage unit maintained at the acquired value of the first temperature sensor SE1 acquired immediately before being pulled out is used. However, the in-flight temperature Tin (n) acquired in step S101 of the first temperature calculation process at this time is overwritten by the _in -flight temperature Tin in the storage unit in step S103, and the _in -flight temperature Tin (n) _in the storage unit is changed. Will be updated. Therefore, in the first temperature calculation process in the second and subsequent control cycles, the in-flight temperature acquired from the first temperature sensor SE1 during the previous control cycle is used as the previous _in -flight temperature Tin (n-1) in the calculation. ..

When it is determined in step S608 that TM ≧ Tth (Yes), the control unit 100 acquires the in-flight temperature from the first temperature sensor SE1 and stores the acquired _in -flight temperature Tin (n) in the storage unit. Overwrite each temperature _TB corresponding to each cartridge 50K and 50Y of the above, and update each temperature _TB in the storage unit (S610). That is, after the drawer 60 is pulled out from the image forming position (S601: Yes), the control unit 100 sets the elapsed time TM to a predetermined time when the drawer 60 is moved to the image forming position (S605: Yes). When it is Tth or more (S608: Yes), the first temperature sensor does not use each temperature _TB in the storage unit as the previous control temperature (each temperature _TB before being updated in step S610). Each temperature _TB in the storage unit as the control temperature is set based on the acquired value of SE1.

After step S609 or step S610, the control unit 100 determines whether or not the end condition of the cooling control is satisfied (S611). Here, the end condition of the cooling control is the process of steps S201 to S203 in the process of FIG. 7. That is, in step S611, the control unit 100 determines whether or not the higher temperature _TB of the temperature _TBs corresponding to the cartridges 50K and 50Y stored in the storage unit is equal to or lower than the first threshold value T1. Is determined.

If it is determined in step S611 that the end condition is satisfied (Yes), the control unit 100 stops the cooling control (S612). If the cooling control has already been stopped in step S604, which is a process prior to step S612, the control unit 100 does nothing in step S612.

That is, when the drawer 60 is moved to the image forming position (S605: Yes) after the elapsed time TM reaches the predetermined time Tth or more, the control unit 100 has already stopped the cooling control in step S604. Therefore, nothing is done in step S612. On the other hand, when the drawer 60 is moved to the image forming position when the elapsed time TM is less than the predetermined time Tth (S605: Yes), the process of step S604 is not executed, so that the control unit 100 Stops the cooling control in step S612 based on each temperature _TB corresponding to each cartridge 50K and 50Y as the control temperature.

After step S612 or when it is determined as No in step S611, the control unit 100 determines whether or not the front cover 11 is closed based on the signal from the front cover open / close sensor 11A (S613). If it is determined in step S613 that the front cover 11 is closed (Yes), the control unit 100 ends this process. If it is determined in step S613 that the front cover 11 is not closed (No), the control unit 100 returns to the process of step S601.

If it is determined in step S601 that the drawer 60 has not been pulled out (No), the control unit 100 executes the first temperature calculation process shown in FIG. 6 (S614). After step S614, the control unit 100 proceeds to the process of step S611.

The operation and effect of the color printer 1 configured as described above will be described.
When the developing roller 52 rotates due to the warming operation performed during the printing operation or before the printing operation, the temperature of the layer thickness regulating blade 53 rises due to friction or the like. Further, when the fixing device 80 is in the ON state, the layer thickness regulating blade 53 is heated by the heat from the fixing device 80.

In the color printer 1, the layer thickness regulation blade 53 is based on the in-machine temperature detected by the first temperature sensor SE1 by the control unit 100, the outside air temperature detected by the second temperature sensor SE2, and the driving state of the developing roller 52. The temperature is calculated, and when the temperature of the layer thickness regulating blade 53 becomes higher than the second threshold value T2, the cooling control is executed. As a result, the cooling control is appropriately executed, and the deterioration of the toner can be suppressed.

Then, the control unit 100 changes the constant used in the calculation of the temperature of the layer thickness regulating blade 53 according to the driving state of the developing roller 52, so that the temperature change of the cartridge 50 due to the difference in the driving state of the developing roller 52 is different. Can be calculated in consideration of. Thereby, the cooling control can be appropriately executed.

Further, the sheet P heated through the fixing device 80 as in the case where only the cold sheet P is supplied to the image forming unit 30 as in the case of executing single-sided printing and in the case of executing double-sided printing. There is a difference in the temperature change of the cartridge 50 between the case where Since it changes depending on whether double-sided printing is executed or double-sided printing is performed, the calculation can be performed in consideration of the difference in temperature change of the cartridge 50 between the case of performing single-sided printing and the case of performing double-sided printing.

When printing on small size paper, the heat capacity of the sheet P is small, so that the amount of heat transferred from the cartridge 50 to the sheet P is smaller than when printing on a sheet P larger than the small size paper, and the temperature of the cartridge 50. Is easy to rise. In the present embodiment, the control unit 100 changes the constant used in the calculation of the temperature of the layer thickness regulating blade 53 between the case of printing on small size paper and the case of printing on a sheet P larger than the small size paper. Therefore, the calculation can be performed in consideration of the difference in the temperature change of the cartridge 50 due to the difference in the size of the sheet P.

Further, since the control unit 100 changes the constant used in the calculation of the temperature of the layer thickness regulating blade 53 according to the operating state of the fan 14, the difference in the temperature change of the cartridge 50 due to the difference in the cooling effect in the machine by the fan 14 Can be calculated in consideration of.

Then, since the control unit 100 changes the constant used in the calculation of the temperature of the layer thickness regulating blade 53 according to the operating state of the fixing device 80, the difference in the temperature change of the cartridge 50 depending on the operating state of the fixing device 80 is taken into consideration. Can be calculated.

In the present embodiment, since the cartridge 50 is not provided with the temperature sensor, the cost of the cartridge 50 can be suppressed.

Further, since the first temperature sensor SE1 is arranged at a position between the fixing device 80 and the cartridge 50 in the main body housing 10, the first temperature sensor SE1 moves from the fixing device 80 toward the cartridge 50. The heat can be measured.

Since the second temperature sensor SE2 is arranged facing the intake port 15, the second temperature sensor SE2 can appropriately measure the outside air temperature taken into the main body housing 10.

When the drawer 60 is placed at the image forming position again and the elapsed time TM after the drawer 60 is pulled out is less than the predetermined time Tth, the value acquired by the first temperature sensor SE1 is before the drawer 60 is pulled out. It is highly possible that it will not change much. Therefore, in this case, an appropriate control temperature can be obtained by calculating the control temperature based on the acquired value of the first temperature sensor SE1 and the previous control temperature. Further, when the drawer 60 is placed at the image forming position again and the elapsed time TM is the predetermined time Tth or more, the value acquired by the first temperature sensor SE1 may be significantly different from that before the drawer 60 is pulled out. high. Therefore, in this case, an appropriate control temperature can be obtained by setting the control temperature based on the acquired value of the first temperature sensor SE1 without using the previous control temperature.

When the drawer 60 is pulled out from the image forming position, it is used for control based on the acquired value of the first temperature sensor SE1 acquired immediately before the drawer 60 is pulled out from the image forming position and the previous control temperature. Since the temperature is calculated, it is possible to more accurately calculate the control temperature in the first temperature calculation process after the drawer 60 is placed at the image forming position again.

The first contact CN1 and the second contact CN2 that are connected when the drawer 60 is placed at the image forming position and separated when the drawer 60 is removed from the image forming position are attached to the drawer 60 and the main body housing 10, respectively. Since it is provided, when the control unit 100 cannot obtain a response from the first temperature sensor SE1, it can be determined that the drawer 60 is out of the image forming position.

Since the air volume of the fan 14 is increased in the cooling control, the inside of the main body housing 10 can be cooled by blowing air from the fan 14.

By reducing the number of printed pages per unit time in the cooling control, for example, the operating amount of the cartridge 50 can be reduced and the amount of heat generated from the fixing device 80 can be suppressed, so that the cartridge 50 can be cooled satisfactorily. be able to.

Since the temperature of the new cartridge 50 is close to the outside air temperature, it is controlled by setting the control temperature based on the acquired value of the second temperature sensor SE2 which is the outside air temperature when the new cartridge 50 is replaced. The temperature can be calculated appropriately.

By providing the first temperature sensor SE1 on the upstream side of the cartridge 50 in the drawer direction D of the drawer 60, the first temperature sensor SE1 is in the main body casing 10 in a state where the drawer 60 is arranged at the image forming position of the main body housing 10. Since it is located near the center of the body 10 where the temperature tends to rise, the control temperature should be calculated appropriately based on the temperature of the part of the main body housing 10 where the temperature tends to rise, and appropriate cooling control should be performed. Can be done.

Even in a situation where the drawer 60 is removed from the image forming position and the acquired value cannot be acquired from the first temperature sensor SE1, the cooling control is stopped when the elapsed time TM becomes Tth or more for a predetermined time, so that the cooling control can be performed. It is possible to prevent it from being continued in vain. When the elapsed time TM is Tth or more for a predetermined time, it is highly possible that the cartridge 50 is exposed to the outside air for a long time and is sufficiently cooled, so that there is no problem even if the cooling control is stopped.

If the drawer 60 is placed at the image forming position when the elapsed time TM is less than the predetermined time Tth, the cooling control is stopped based on the control temperature, so that the cooling control is stopped based on the appropriate control temperature. Can be made to.

Since the cooling control is executed at the control temperature corresponding to the cartridge 50 having the higher temperature among the cartridges 50K and 50Y having different installation conditions, the first cartridge 50K and the second cartridge 50Y can be cooled satisfactorily. ..

Since the first control temperature is calculated based on the first function, the first control temperature can be calculated more accurately. Since the second control temperature is calculated based on the second function, the second control temperature can be calculated more accurately.

In the monochrome mode, the operating first cartridge 50K is the target for calculating the first control temperature, and the non-operating second cartridge 50Y is targeted for calculating the second control temperature. Therefore, the operation of the cartridge 50 depends on the type of image to be formed. Even when the amount changes, the first control temperature and the second control temperature can be calculated more accurately.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. The specific configuration can be appropriately changed without departing from the spirit of the present invention.

In the above embodiment, when the elapsed time TM is equal to or longer than the predetermined time Tth when the drawer 60 is placed at the image forming position again, the acquired value of the first temperature sensor SE1 is set as the control temperature ( _TB ). However, the present invention is not limited to this, and the control temperature may be set based on the acquired value of the first temperature sensor, such as multiplying the acquired value of the first temperature sensor by a predetermined coefficient.

In the above embodiment, it is determined whether the drawer 60 is arranged at the image forming position by connecting / disconnecting the first contact CN1 and the second contact CN2, but the present invention is not limited to this, and for example, the position of the drawer. It may be determined whether or not the drawer is arranged at the image forming position by the sensor that detects.

In the above embodiment, when it is determined that the cartridge 50 has been replaced, the acquired value of the second temperature sensor SE2 is set as the control temperature ( _TB ), but the present invention is not limited to this, and the second temperature is not limited to this. The control temperature may be set based on the acquired value of the second temperature sensor, such as multiplying the acquired value of the sensor by a predetermined coefficient.

In the above embodiment, the cartridge 50 without the photosensitive drum 61 is exemplified, but the present invention is not limited to this, and the cartridge may be provided with the photosensitive drum, for example.

In the above embodiment, the photosensitive drum 61 is exemplified as an example of the photoconductor, but the present invention is not limited to this, and the photoconductor may be, for example, a belt-shaped photoconductor.

In the above embodiment, as the cooling control, the control of the fan 14, the reduction of the number of printed pages, and the stop of printing are performed stepwise according to the temperature _TB , but the present invention is not limited thereto. For example, the cooling control may control only the fan 14.

In the above embodiment, in principle, the control temperature is obtained by calculation using the first function or the like, but the present invention is not limited to this, and for example, the acquired value of the first temperature sensor is always used as the control temperature. It may be set.

In the above embodiment, the yellow toner is exemplified as an example of the chromatic color developer, but the present invention is not limited to this, and the chromatic color developer is, for example, a chromatic color toner other than yellow such as magenta. There may be.

In the above embodiment, two of the four cartridges 50K and 50Y are subject to temperature calculation, but the present invention is not limited to this, and three or more cartridges may be subject to temperature calculation, or one cartridge. May be the target of temperature calculation.

In the above embodiment, in step S602 and step S608, the elapsed time TM is compared with the predetermined time Tth which is the same threshold value, but the present invention is not limited thereto. For example, in step S602, it is determined whether the elapsed time TM is the first predetermined time Tth1 or more, and in step S608, it is determined whether the elapsed time TM is the second predetermined time Tth2 or more different from the first predetermined time Tth1. You may.

In the above embodiment, the drawer 60 is configured to include the first temperature sensor SE1, but the cartridge 50 may be configured to include the first temperature sensor SE1. As shown in FIG. 10, in the configuration in which the cartridge 50K includes the first temperature sensor SE1, the drawer 60 is pulled out so that the cartridge 50K is taken out from the main body housing 10 and the drawer 60 is arranged at the image forming position. As a result, the cartridge 50K is mounted on the main body housing 10.

When the elapsed time from the cartridge 50K being taken out from the main body housing 10 is less than a predetermined time, the control unit 100 controls the cartridge 50 based on the acquired value of the first temperature sensor SE1 and the previous control temperature. Calculate the temperature. Further, when the elapsed time from the cartridge 50K being taken out from the main body housing 10 is a predetermined time or more, the control unit 100 calculates the control temperature based on the acquired value of the first temperature sensor SE1.

The control unit 100 continues the cooling control when the cartridge 50K is taken out from the main body housing 10 during the cooling control. Further, the control unit 100 stops the cooling control when the elapsed time from the cartridge 50K being taken out from the main body housing 10 becomes more than a predetermined time in the state where the cartridge 50K is taken out from the main body housing 10. ..

In the embodiment of FIG. 10, the temperature sensor SE1 is provided on the cartridge 50 attached to and detached from the drawer 60, but the present invention is not limited to this, and the temperature sensor is attached to the cartridge attached to and detached from the main body housing such as a monochrome printer. It may be provided to carry out the control of the present invention.

In the above embodiment, the present invention is applied to the color printer 1, but the present invention is not limited to this, and the present invention may be applied to other image forming devices such as a copying machine and a multifunction device.

In the above embodiment, the control unit 100 switches the constant for calculating the control temperature between single-sided printing and double-sided printing, but the configuration of the control unit is not limited to this. For example, even if the control unit switches a constant for calculating the control temperature between when printing on the first surface of the sheet P and when printing on the second surface of the sheet P. good.

The fixing device is not limited to the above embodiment. For example, the fixing device may be configured to include a fixing belt, a nip plate, and a pressurizing member that sandwiches a sheet between the nip plates.

Each element described in the above-described embodiment and modification may be arbitrarily combined and carried out.

1 Color printer 10 Main unit housing 50 Cartridge 60 Drawer 100 Control unit SE1 1st temperature sensor _TB temperature TM Elapsed time Tin (n) _In -flight temperature Tth Specified time

Claims (11)

With the main body housing
A drawer that holds a cartridge that houses the developer and can be pulled out from the image forming position of the main body housing.
The first temperature sensor provided in the drawer and
With a control unit,
The control unit
It is possible to start and stop the cooling control for cooling the inside of the main body housing based on the control temperature based on the acquired value of the first temperature sensor.
When the drawer is removed from the image forming position during the cooling control, the cooling control is continued.
It is characterized in that, in a state where the drawer is removed from the image forming position, the cooling control is stopped when the elapsed time from the removal of the drawer from the image forming position becomes a predetermined time or more. Image forming apparatus. The control unit
Claim 1 is characterized in that when the drawer is moved to the image forming position and the elapsed time is less than the predetermined time, the cooling control is stopped based on the control temperature. The image forming apparatus according to. It is equipped with a fan that cools the inside of the main body housing.
The control unit
The image forming apparatus according to claim 1 or 2, wherein in the cooling control, the air volume of the fan is increased as compared with the case where the cooling control is not executed. The control unit
The image forming apparatus according to any one of claims 1 to 3, wherein the control temperature is calculated based on the acquired value of the first temperature sensor and the operating amount of the cartridge. The drawer comprises a first contact that conducts with the first temperature sensor.
The main body housing has a second contact that conducts with the control unit.
When the drawer deviates from the image forming position, the first contact is separated from the second contact.
The image forming apparatus according to any one of claims 1 to 4, wherein when the drawer is arranged at the image forming position, the first contact is connected to the second contact. .. Equipped with a second temperature sensor to acquire the outside temperature,
The control unit
Any of claims 1 to 5, wherein the control temperature is calculated based on the acquired value of the first temperature sensor, the operating amount of the cartridge, and the acquired value of the second temperature sensor. The image forming apparatus according to claim 1. The image forming apparatus according to any one of claims 1 to 6, wherein the cartridge includes a developing roller and an accommodating portion for accommodating a developing agent. The image forming apparatus according to claim 7, wherein the drawer includes a photoconductor. The image forming apparatus according to any one of claims 1 to 8, wherein the first temperature sensor is provided on the upstream side of the cartridge in the drawer drawing direction of the drawer. Equipped with a fixing device to fix the developer image on the sheet
The image forming apparatus according to any one of claims 1 to 9, wherein the first temperature sensor is provided at a position between the cartridge and the fixing device. With the main body housing
A cartridge that can be attached to and detached from the main body housing and stores the developer,
The first temperature sensor provided on the cartridge and
With a control unit,
The control unit
It is possible to start and stop the cooling control for cooling the inside of the main body housing based on the control temperature based on the acquired value of the first temperature sensor.
When the cartridge is taken out from the main body housing during the cooling control, the cooling control is continued.
It is characterized in that, in a state where the cartridge is taken out from the main body housing, the cooling control is stopped when the elapsed time from the cartridge being taken out from the main body housing becomes a predetermined time or more. Image forming device.

Images