JPH11330755A - Electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce noise by fitting an optional substrate detachably, cooling a power supply part for supplying power to a control part, and reducing the drive amount of a cooling means, when the optional substrate is not fitted. SOLUTION: When an optional substrate 60 is fitted to an optional substrate interface 57, a second fan repeats the drive/stop of a fan motor 36a. Even if the amount of heat being generated by a substrate for power supply is increased due to the fitting of the optional substrate 60, the overheating of the substrate can be prevented. When the optional substrate 60 is attached or detached, a sleep mode is switched to. After an image is formed when no optional substrate 60 is fitted, the second fan is stopped immediately, the amount of heat being generated by the substrate for power supply is small, and almost no cooling is required other than in the formation of the image. In a laser printer, the second fan motor 36a is controlled in this manner, thus preventing noise from being generated in the sleep mode. More specifically, the amount of drive for the second fan is set according to the amount of heat which is generated in the substrate for power supply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic apparatus on which an optional board can be mounted as desired, and more particularly, a control section on which the optional board is removably mounted and executes various controls, and the control section. A power supply for supplying power to the
The present invention relates to an electronic device including a cooling unit for cooling the power supply unit.

[0002]

2. Description of the Related Art Conventionally, in an electronic device of this type, a new function can be added to a control executed by a control unit or a function can be changed by mounting an option board. For example, in an image forming apparatus such as a laser printer, by adding a memory as a buffer as an optional board, a large amount of print data can be received from an external device such as a computer to speed up image forming processing. By mounting an interface board as an optional board, print data can be received in a different method (for example, serial or parallel) from before.

Power for the control unit to execute various controls is supplied from a power supply unit. In this power supply, transformer,
Rectification and the like are often performed, and in this case, the power supply unit generates heat. Therefore, in these electronic devices, a cooling air is generated by a fan or the like, and the power supply unit is cooled by the cooling air.

[0004]

However, the amount of heat generated by the power supply unit may be different between when the optional board is mounted and when it is not mounted. Therefore, in the conventional electronic device, the number of rotations of the fan and the like are set on the assumption that the heat generation amount of the power supply unit becomes the highest value conceivable due to the mounting of the option board. In this case, when the optional board is not mounted or when the optional board that does not increase the heat generation of the power supply unit is mounted, the fan rotates at an excessive number of rotations, which causes noise. In particular, the image forming apparatus has a so-called sleep state in which the power is turned on but no image is formed, and it is desired to reduce noise in such a state.

Accordingly, it is an object of the present invention to provide an electronic apparatus capable of appropriately driving a cooling means for cooling a power supply unit and reducing noise.

[0006]

According to an aspect of the present invention, there is provided an electronic apparatus capable of mounting an optional board as a board to be mounted as desired. A controller that detachably mounts the option board, performs various controls, a power supply that supplies power to the controller, a cooling unit that cools the power supply, and when the option board is not mounted, And a cooling control means for reducing a driving amount of the cooling means as compared with a time when the optional board is mounted.

[0007] In the present invention thus configured, an optional board is detachably mounted on the control unit, and the control unit executes various controls. The power supply unit supplies power to the control unit, and the cooling unit cools the power supply unit. Here, the cooling control means reduces the driving amount of the cooling means when the optional board is not mounted, compared to when the optional board is mounted. In other words, in general, when the optional board is not mounted, the power supply unit generates less heat than when the optional board is mounted.
The driving amount of the cooling means may be reduced. As described above, according to the present invention, the drive amount of the cooling unit can be set to an appropriate value according to the heat generation amount of the power supply unit based on the mounting / non-mounting of the optional board. Therefore, it is possible to satisfactorily reduce noise caused by driving the cooling means.

[0008] The mounting / non-mounting of the optional board is as follows.
As shown below, a detection unit may be provided to perform the detection automatically, and the user may operate a switch or the like when the optional board is mounted or detached. According to a second aspect of the present invention, in addition to the configuration of the first aspect, there is further provided a detecting means for detecting the mounting of the optional board, wherein the cooling control means is configured to control the driving amount based on a detection result of the detecting means. Is controlled.

In the present invention, the mounting / non-mounting of the option board is automatically detected by the detecting means, and the driving amount can be controlled by the cooling control means based on the detection result. For this reason, the drive amount of the cooling unit can be reliably controlled to the drive amount according to the mounting / non-mounting of the optional substrate. Therefore, in addition to the effects of the invention described in claim 1,
There is an effect that noise associated with driving of the cooling means can be more reliably reduced.

[0010] The third aspect of the present invention is the first or second aspect.
In addition to the configuration described above, the image forming apparatus further includes an image forming unit that forms an image on a recording medium, wherein the cooling control unit drives the cooling unit when the image forming unit is not driven, compared to when the image forming unit is driven. The driving amount of the cooling means is further reduced at least when the optional substrate is not mounted, at least when the optional substrate is not mounted, compared to when the optional substrate is mounted.

Since the present invention includes the image forming means, it is possible to form an image on a recording medium. An electronic apparatus (so-called image forming apparatus) having this type of image forming means is powered on but does not drive the image forming means, and thus does not form an image. ) And when the image forming unit is driven to actually form an image. At the time of driving, the heat generation of the power supply unit also increases, but the image forming means itself also generates noise. For this reason, at the time of driving the image forming unit, noise does not matter even if the driving amount of the cooling unit is sufficiently increased. When the image forming unit is not driven, the noise generated by the cooling unit becomes conspicuous, but since the heat generated by the power supply unit is reduced, the driving amount of the cooling unit is reduced to reduce the noise. Also in this case, similarly to the first aspect of the present invention, the cooling unit is driven in accordance with the mounting / non-mounting of the optional board, and the driving amount of the cooling unit can be minimized to reduce the noise satisfactorily. .

Therefore, according to the present invention, in addition to the effects of the first and second aspects of the present invention, there is an effect that the driving amount of the cooling unit can be controlled depending on whether the image forming unit is driven or not. . Further, since the noise can be reduced as described above when the image forming means is not driven, the effect of the first or second aspect of the invention is more remarkably exhibited.

The present invention can be applied to a so-called electrophotographic image forming apparatus provided with a heat fixing device for heating and fixing a toner image. In this case, it is necessary to cool the outer periphery of the heating / fixing unit when the image forming unit is driven (the cooling may be performed by another cooling unit as described later). When it is not driven, almost no noise is generated. In the present invention,
As described above, since the noise when the image forming means is not driven can be reduced favorably, the effect of the present invention is more remarkably exhibited when applied to this type of image forming apparatus.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect, the apparatus further comprises another cooling means for cooling the image forming means, wherein the cooling control means comprises a cooling means for cooling the power supply section. It is characterized in that only the driving amount is controlled as described above. In the present invention, the image forming unit is cooled by another cooling unit other than the cooling unit. For this reason, it is not necessary to consider heat generation of the image forming unit when determining the driving amount of the cooling unit. As described above, the cooling unit is driven in accordance with the mounting / non-mounting of the optional substrate, thereby reducing noise satisfactorily. can do. Further, overheating of the image forming means can be favorably prevented by the other cooling means.

As described above, according to the present invention, the control of the cooling control means can be further simplified, and the cooling means can be driven more appropriately in accordance with the heat generated by the power supply unit. Therefore, in addition to the effect of the third aspect of the present invention, there is an effect that the control of the cooling means by the cooling control means is efficiently performed and the noise can be further reduced.

According to a fifth aspect of the present invention, in addition to the configuration according to any one of the first to fourth aspects, when the optional board is mounted, the option board increases heat generation of the power supply unit by the mounting. Board determination means for determining whether or not the heat generation of the power supply section is reduced when the optional board does not increase the heat generation of the power supply section based on the determination result of the board determination means. The driving amount of the cooling unit is reduced as compared with the case where the number of the optional boards is increased.

According to the present invention, when the optional board is mounted, it can be determined by the board determining means whether or not the optional board increases the heat generated by the power supply unit. Then, based on the determination result of the board determination means, the cooling control means, when the optional board that does not increase the heat generation of the power supply unit is mounted, controls the driving amount of the cooling means compared to when the optional board that increases the heat generation of the power supply part is mounted. Reduce. That is, even if the optional board is mounted, if the board does not increase the heat generation of the power supply unit, the driving amount of the cooling means necessary for cooling the power supply unit is not so large. Therefore, in this case, the driving amount of the cooling means is relatively reduced. For this reason, the cooling means can be driven more appropriately. Therefore, according to the present invention, in addition to the effect of the invention described in any one of claims 1 to 4, an effect that the noise can be more favorably reduced is generated.

According to a sixth aspect of the present invention, in addition to the configuration of any one of the first to fifth aspects, the cooling means generates a cooling air by rotating, and a drive for rotating the fan. And a motor. For this reason, in the present invention, the power supply can be cooled by generating cooling air by rotating the fan by the drive motor. However, in an electronic device having this type of cooling means, relatively loud noise is generated due to wind noise generated by a fan or the like. On the other hand, according to the present invention, the drive amount of the cooling unit can be appropriately set as described above to reduce noise. Therefore, in the present invention, the effect of the invention described in any one of claims 1 to 5 appears more remarkably.

[0019]

Next, an embodiment of the present invention will be described with reference to the drawings. 1 to 3 show a configuration of a laser printer 1 as an electronic apparatus to which the present invention is applied. FIG. 1 is a cross-sectional view of a main part, FIG. 2 is a cross-sectional view of a main part, and FIG. It is. As shown in FIG. 1, the laser printer 1 includes a paper feed tray 3 provided on a rear upper side of a main body case 2 as a casing, and an openable top cover provided on a front upper side of the main body case 2. 4 constitutes the appearance.

As shown in FIG. 1 and FIG.
Inside, a power supply substrate 32 as a power supply unit, a control substrate 33 as a control unit, a paper transport mechanism 5, a scanner unit 6, a process unit 7, a fixing unit 8 as a fixing unit, and the like are provided. As shown in FIG. 2, the power supply substrate 32 is disposed on the rear side (the left side in FIG. 2) inside the main body case 2, and receives power supplied from an external power supply source to Power is distributed to each part. A capacitor, a transformer, a high-voltage power supply, a low-voltage power supply and the like (all not shown) are provided on the power supply substrate 32. Fever. Also, the control board 33
Is located on the side (right side in FIG. 2) adjacent to the power supply board 32 in the rear part of the main body case 2, and on the board is necessary for performing various controls of the laser printer 1. Various members (described in detail later) are provided.

A power supply board 32 and a control board 33
A process unit 7 is disposed in the front adjacent to the process unit 7 and substantially at the center in the main body case 2, and a fixing unit 8 is provided in the front adjacent to the process unit 7 and in the front part in the main case 2. Is arranged. Further, the fixing unit 8 fixes a predetermined toner image formed on a sheet by heat, as described later, and has a considerably high temperature during image formation. Further, as shown in FIG. 1, a space 34 having a predetermined width is formed along the longitudinal direction below the process unit 7 and the fixing unit 8 which are arranged adjacent to each other.

The scanner unit 6, the process unit 7, and the fixing unit 8 are configured as image forming means for forming an image on a sheet (not shown) as a recording medium. Next, the configuration of the image forming unit will be described with reference to FIG. The paper feed tray 3 is capable of setting sheets in a stacked state, and includes a pickup roller 9 for feeding the stacked sheets one by one. The paper transport mechanism 5 is for transporting the paper fed from the paper feed tray 3 to the process unit 7, and includes a pair of registration rollers 10 provided at the lower end of the paper feed tray 3.

The paper fed from the paper feed tray by the pick-up roller 9 is sent to a pair of registration rollers 10, where the leading edge of the paper is aligned by stopping the registration roller 10, and the process unit is rotated by the normal rotation of the registration roller 10. 7 is conveyed. The scanner unit 6 is provided below the process unit 7 and includes a laser emitting unit (not shown), a polygon mirror 11, reflecting mirrors 12 and 13,
And a lens 14 and the like. Then, the laser beam L emitted from the laser emitting unit based on image data or the like passes or reflects in the order of the polygon mirror 11, the lens 14, the reflecting mirror 12, and the reflecting mirror 13, and the photosensitive drum 17 of the process unit 7, which will be described later. Irradiation is performed by high-speed scanning on the surface of.

The process unit 7 includes a unit case 1
6, a photosensitive drum 17 as an electrostatic latent image carrier, a developing roller 18 as a toner carrier, a supply roller 19, a scorotron charger 20, a transfer roller 21, a cleaning roller 22, and a toner cartridge 23 And the like, and has a cartridge structure that can be attached to and detached from a predetermined portion in the main body case 2. When the process unit 7 is detached from the main body case 2, the toner cartridge 23 can be mounted on the process unit 7 so that toner can be supplied. The toner in the toner cartridge 23 is agitated by the agitator 25 and discharged from the toner supply port 26 opened on the side of the toner cartridge 23. The toner used here is a non-magnetic one-component toner. A supply roller 19 is rotatably disposed on the side of the toner supply port 26, and a developing roller 18 is rotatably disposed opposite the supply roller 19. The photosensitive drum 17
At a side position of the developing roller 18, the developing roller 18 is in contact with the developing roller 18 in an opposed manner and is rotatably disposed. The supply roller 19, the developing roller 18, and the photosensitive drum 17 are all rotated clockwise in FIG.

The portion of the surface of the photosensitive drum 17 which comes into contact with the developing roller 18 is acted upon by the laser beam L emitted from the scorotron-type charger 20 and the scanner unit 6 just before reaching the contact portion. An electrostatic latent image corresponding to the image data or the like is formed. For this reason,
Supplying the toner discharged from the toner supply port 26 to the supply roller 1
9 and the developing roller 18, the toner is carried on the surface of the developing roller 18, thinned by the layer thickness regulating blade 15 and brought into contact with the photosensitive drum 17. Then, development is performed.

Above the photosensitive drum 17, a transfer roller 21 facing the photosensitive drum 17 is provided.
The paper is transferred to the paper when passing between the transfer roller 21 and the paper, and the paper is sent into the fixing unit 8. The toner remaining on the surface of the photosensitive drum 17 is temporarily collected by the cleaning roller 22, returned to the photosensitive drum 17 at a predetermined timing, and collected by the developing roller 18.

The fixing unit 8 fixes the image transferred on the sheet by heat, and includes a heating roller 28,
A pressing roller 29 pressed by the heating roller 28, and a pair of discharging rollers 30 provided downstream of the rollers 28 and 29 for discharging the sheet to the outside of the main body case 2.
Is provided. In the fixing unit 8, the transferred toner is thermally fixed by the heating roller 28 and the pressing roller 29, and then is discharged onto the discharge tray 31 by the discharge roller 30. The heating roller 28 is
A fixing heater 28a composed of a halogen lamp is inserted into an aluminum tube whose surface is coated with fluorine, and the toner transferred to the paper is heated and fixed by the heat generated by the fixing heater 28a. .

Laser printer 1 configured as described above
Includes a first fan 35 for forming an air flow between the process unit 7 and the fixing unit 8 and a second fan 36 for cooling the power supply substrate 32.
That is, as shown in FIG. 2, the first fan 35 is disposed in the main body case 2 on the side of the process unit 7 and the fixing unit 8 (on the right side in FIG. 2). 8 is disposed so as to face one end of a space 34 (FIG. 1) formed therebetween. The first fan 35 is configured by a suction fan that operates to take in air into the main body case 2.

On the other hand, as shown in FIG. 2, the second fan 36 is disposed on the side adjacent to the power supply board 32 in the main body case 2 and above the control board 33. Second
In such a position, the fan 36 is disposed slightly behind the power supply board 32 and slightly inclined so that the fan faces the power supply board 32. This second fan 36
Is constituted by an exhaust fan that operates to discharge air from inside the main body case 2.

Further, as shown in FIG.
A first fan suction / exhaust port 37 for taking in outside air into the main body case 2 by the first fan 35 is provided on a right side wall of the main body case 2 facing on the side closer to. As shown in FIGS. 2 and 3, a second fan 3 is provided on the rear side wall of the main body case 2 facing the side close to the second fan 36.
6, a second fan intake / exhaust port 38 for exhausting air from the inside of the main body case 2 is provided.

When the first fan 35 and the second fan 36 are provided, the operation of the first fan 35 causes the flow of air into the space 34 formed between the process unit 7 and the fixing unit 8. Is formed, the heat generated in the fixing unit 8 flows along the flow of the air. Therefore, the heat generated in the fixing unit 8 is not transmitted to the process unit 7 as it is, so that the toner in the process unit 7 is prevented from being deteriorated by the heat, and a good image can be formed. On the other hand, since the power supply board 32 is separately cooled by the operation of the second fan 36, heat generated in the power supply board 32 is also efficiently removed. Therefore, in order to cope with an increase in the image forming speed of the laser printer 1, even if a high-output driving member is used and a large-capacity power supply corresponding to the driving member is provided on the power supply substrate 32, the efficiency is improved by the second fan 36. Cooling can be achieved, and the temperature rise can be effectively suppressed. Therefore, the members that generate heat, that is, the fixing unit 8 and the power supply substrate 32, are appropriately and efficiently cooled inside the main body case 2. Therefore, a rise in the temperature inside the main body case 2 can be effectively suppressed.

Since the first fan 35 is a suction fan and the second fan 36 is an exhaust fan, the outside air is taken into the main body case 2 by the first fan 35, and the main body case 2 is The air inside is discharged outside. Therefore, an air flow (a flow indicated by an arrow 41 in FIG. 2) can be formed between the first fan 35 and the second fan 36 inside the main body case 2. That is, the outside air taken into the main body case 2 by the first fan 35 flows inside the main body case 2 through an efficient path. The upper part of the space 34 where the air flow is formed is almost closed by the upper parts of the process unit 7 and the fixing unit 8 as shown in FIG. This prevents the air from being directly guided to the second fan 36 without passing through. Therefore, it is possible to prevent the outside air taken into the main body case 2 from being directly guided to the second fan 36 without passing through the space 34. Therefore,
Each part can be appropriately cooled by the outside air taken into the inside of the main body case 2, and the taken-in outside air can be cooled effectively without stagnation.

As shown in FIG. 2, on the left side wall of the case 2 main body facing the first fan 35 with the process unit 7 and the fixing unit 8 interposed therebetween, a second side connecting the inside and the outside of the main body case 2 is provided. A first intake / exhaust port 39 as an opening
Is provided. By providing the first intake / exhaust port 39,
A flow of outside air (a flow as indicated by an arrow 42 in FIG. 2) can be formed between the first intake / exhaust port 39 and the first fan 35. For this reason, outside air can flow more efficiently between the process unit 7 and the fixing unit 8. Therefore, heat generated in the fixing unit 8 can be extremely efficiently discharged from the inside of the main body case 2.

Further, as shown in FIG. 2 and FIG. 3, a second opening for communicating the inside and the outside of the main body case 2 is formed in the rear wall of the main body case 2 facing the power supply substrate 32 on the side close to the power supply substrate 32. The second intake / exhaust port 40 is provided. By providing the second intake / exhaust port 40, a flow of outside air (a flow indicated by an arrow 43 in FIG. 2) can be formed between the second intake / exhaust port 40 and the second fan 36. For this reason, the heat generated in the power supply substrate 32 can be more efficiently removed from the main body case 2.
Can be exhausted from inside.

Next, the configuration of the control board 33 will be described. As shown in FIG. 3, the control board 33 can be taken out of the main body case 2 by removing a screw 53 fixing the interface cover 51. On the upper surface of the control board 33, various elements 55 including a CPU 71 and the like described later, an optional board interface 57 on which the user can mount the optional board 60 as desired, And a memory interface 59 to which a memory board 70 (FIG. 6) as an additional memory can be attached. The interface cover 51 is provided with a parallel interface 75 to which parallel data is input.

The option board 60 exemplified in FIG. 4 is a board for receiving serial data in addition to parallel data, and sets a serial interface 61 to which serial data is input, a data input mode and the like. Switches 63 and 65 to perform various kinds of elements 66 such as an IC for performing a process of receiving data input to the interface 61;
And an interface 67 detachably connected to the option board interface 57. Such an option board 60 is connected to the option board interface 57.
When the control board 33 is mounted on the main body case 2 by retightening the screws 53, the serial interface 61, the switch 63, and the switch 63, as shown in FIG. 65 is exposed. Therefore, serial data can be input to the laser printer 1.

Next, the configuration of the control board 33 will be further described with reference to the block diagram of FIG. The control board 33 receives a CPU 71 executing various calculations, a ROM 72 storing various control programs, and parallel data or serial data transmitted from an external data transmission device PC such as a personal computer or a host computer. And a RAM 73 provided with various memories such as a receiving buffer for storing.

The control board 33 includes a timing control circuit (TC) 7 for generating a timing signal for timing of writing / reading the reception data to / from the reception buffer.
4, an interface (I / F) 75 for receiving transmitted parallel data, and a video interface (VI / I / F) having a scan buffer and sequentially outputting print data converted to bit image data to the DC controller circuit 82. F) 76, a sensor interface (S / I / F) 77 for receiving detection signals from other sensors including a toner sensor 83 for detecting the presence or absence of toner in the toner cartridge 23, and a surface of the laser printer 1. The user can select various control modes from the operation panel 1c provided in the control panel 1c, and receives a panel interface (P / I / F) 78 for receiving the switched signal, the optional board interface (OP / I / F) 57 and the memory interface (M (I / F) 59, which are connected to the CPU via the bus 81. 1, ROM72, and RAM73
It is connected to the.

The DC controller circuit 82 includes a pickup roller 9, a registration roller 10, a developing roller 18,
Supply roller 19, photosensitive drum 17, transfer roller 21, cleaning roller 22, heating roller 28, pressing roller 2
9 and a main motor 84 for driving the discharge roller 30 and the like.
Drive circuit 87, a drive circuit 89 for a laser diode 85 constituting the laser emitting section, a drive circuit 90 for a scanner motor 86 for driving the polygon mirror 11, and a drive circuit 90 for the fixing heater 28a. Drive circuit 9
1, a photosensitive drum 17, a transfer roller 21, a charger 20,
A predetermined voltage is applied to the developing roller 18 and the cleaning roller 22, and a high-voltage board 92 for turning on a discharge lamp 88 for discharging the photosensitive drum 17, and a drive for a first fan motor 35 a for driving the first fan 35. Circuit 93
And a second fan motor 36a for driving the second fan 36
And a driving circuit 94 for each.

The ROM 72 has various control programs as an ordinary laser printer, a program of a flowchart described later, a font memory storing printing dot pattern data relating to a large number of characters such as characters and symbols, and a RAM 73. A memory management program that manages the memory capacity and the start address of each memory such as a reception data buffer and a print image memory provided in advance is stored in advance.

The optional board interface 57
As shown in FIG. 7, a grounded electrode 57a and D
And an electrode 57b connected to the C controller circuit 82. Further, a reference voltage of 5 V is applied to the electrode 57b via the resistor 99. For this reason, CP
By reading the signal input to the DC controller circuit 82 from the electrode 57b, the U71 can detect the presence or absence of the option board 60 as follows. That is, when the optional board 60 is mounted, the electrodes 57
a and 57b are short-circuited, and a low-level signal is input to the DC controller circuit 82 from the electrode 57b. When the option board 60 is not mounted, the electrode 57b is opened, and a high-level signal is input to the DC controller circuit 82 from the electrode 57b. The CPU 71 can determine the presence or absence of the option board 60 by reading this state.

Here, in addition to the image forming mode set at the time of image formation, the CPU 71 has the following sleep mode and standby mode as processing modes in order to save power consumption other than at the time of image formation. Sleep mode refers to CP
U71 reads a signal from the operation panel 1c and supplies power to the control board 33.
Drive circuits 87 to 91 to each part except 6 or high-voltage board 9
This is a processing mode in which the energization via 2 is completely suspended.
The standby mode is a processing mode in which the temperature of the fixing heater 28a is maintained at a predetermined temperature (for example, 180 ° C.) lower than the temperature (for example, 200 ° C.) set at the time of image formation. The temperature is different, and
The image forming mode is the same as the image forming mode except that the driving modes of the fans 35 and 36 are different as described later.

The amount of heat generated by the fixing unit 8, the power supply substrate 32, and the like differs depending on whether the CPU 71 is in the sleep mode, the standby mode, or the image forming mode. Therefore, the CPU 71 controls the driving amounts of the first fan 35 and the second fan 36 in accordance with the state of the laser printer 1 as follows.

FIG. 8 is a flowchart showing a process related to the above-mentioned mode switching executed by the CPU 71.
After turning on the power, the CPU 71 repeatedly executes this processing. As shown in FIG. 8, when power is turned on, S0 (S0
Represents a step: the same applies to the following).
Is preheated, and the temperature is raised to 180 ° C. corresponding to the standby mode. In the following S1, the standby mode is set and the fixing heater 2 is set.
8a is maintained at 180 ° C., and each section is controlled similarly to the image forming mode. In this standby mode, the first
The fan 35 is driven at half speed, and the second fan 36 is stopped. That is, during normal image formation, the CPU 7
1 is a first fan motor 3 via drive circuits 93 and 94
5a, a voltage of 24 V is applied to the second fan motor 36a, and the fans 35, 36 are driven at about 4000 rpm (full speed). However, in this standby mode, the driving circuit 93
, A voltage of 16V is applied to the first fan motor 35a, and only the first fan 35 is driven at about 2500 rpm (half speed).

In the following S2, a predetermined time (for example, 2
Start a timer to count 0 minutes). Subsequently, it is determined in S3 whether or not data has been received, and if not (S3: NO), it is determined whether or not the operation panel 1c has been operated (S4). If the operation panel 1c is not operated (S4: NO), the timer starts (S4).
It is determined whether or not the predetermined time has elapsed from 2) (S
5) If it has not elapsed (S5: NO), the process directly proceeds to S3, and if it has elapsed (S5: YES), the process proceeds to S6.
Migrate each. As described later, when the process proceeds to the processing after S6, the sleep mode is set. That is,
When the power is turned on, the standby mode is set once (S1), and no data is received or the operation of the operation panel 1c is not performed (S1).
3, S4: NO) When the predetermined time has elapsed (S
5: YES), the standby mode is switched to the sleep mode.

If the data is received (S3: YES) or the operation of the operation panel 1c (S4: YES) is performed before the predetermined time elapses, the process proceeds to S7 and the image forming mode is performed. , And waits until the image forming process by another routine is completed (S8). When the image forming mode is set, the first fan 35 and the second fan 36 are driven at full speed as described above. When the image forming process is completed (S8: YES), the process proceeds to S1, the standby mode is set, and the above process is repeated.

After the power is turned on (S0) or after the end of the image forming process (S8: YES), neither the data reception (S3) nor the operation of the operation panel 1c (S4) is performed during the predetermined time. (S5: YES), and proceeds to S6 to determine whether or not the option board 60 is present. And
Option board 60 is option board interface 5
If it is not mounted on the camera 7 (S6: NO), the sleep mode 1 is set in S9, and the process proceeds to S3. Sleep mode 1 means that the CPU 71 operates the operation panel 1
c, and supplies power also to the control board 33. However, by completely stopping the power supply to each part via the drive circuits 87 to 94 or the high-voltage board 92, the first fan 35 and the second fan In this mode, the fan 36 is also stopped.

On the other hand, when the option board 60 is mounted on the option board interface 57 (S6:
YES), after setting sleep mode 2 in S10,
The process proceeds to S3 described above. The sleep mode 2 is a mode similar to the sleep mode 1 except that the second fan 36 is intermittently driven at half speed. In this case, the second fan 3
No. 6, for example, is driven at a half speed for one minute, and then stopped for 30 minutes, so that driving and stopping are repeated. Therefore, even if the amount of heat generated by the power supply board 32 increases due to the mounting of the option board 60, the power supply board 32
Overheating can be satisfactorily prevented. Further, even after the sleep mode 1 or 2 is set, S3, S4, and S3
6 is repeatedly executed, so that the data is received while the sleep mode 1 or 2 is set (S3: YE
If the operation S) or the operation of the operation panel 1c (S4: YES) is performed, the mode can be shifted to the image forming mode (S7). Switching can be performed.

The first fan 35 and the second fan 35
FIG. 9 shows the manner in which the fan 36 is driven. As shown in FIG. 9, during image formation (image formation mode), the first fan 35,
The second fans 36 are both driven at full speed. Therefore, the process unit 7 and the power supply substrate 32 can be sufficiently cooled, and a good image can be formed. During the image formation, the image forming means itself such as the process unit 7 also generates noise. Therefore, even if the fans 35 and 36 are driven at full speed, the noise (wind noise, etc.) due to the drive is not a noise to the user. No problem.

After the image formation is completed, the first fan 35 is driven at a half speed for the predetermined time (for example, 20 minutes) and then stopped (standby mode). Therefore, it is possible to satisfactorily remove the residual heat of the fixing unit 8 and the like, and satisfactorily prevent the residual heat from affecting the process unit 7 and the like and hindering the next and subsequent image formation.

When the optional board 60 is mounted, the second fan 36 is intermittently driven after the image formation is completed as described above. Therefore, even if the amount of heat generated by the power supply board 32 increases due to the mounting of the option board 60, overheating of the power supply board 32 can be satisfactorily prevented. In addition, the driving amount of the second fan 36 is significantly reduced as compared with during image formation, and is a necessary and sufficient driving amount for preventing the power supply substrate 32 from overheating. For this reason, the noise of the laser printer 1 during sleep can be reduced favorably.

Further, when the option board 60 is not mounted, the second fan 36 is stopped immediately after the image formation is completed. That is, when the option substrate 60 is not mounted, the heat generation amount of the power supply substrate 32 is extremely low, and cooling is hardly required except during image formation. Therefore,
In the laser printer 1, by controlling the second fan 36 in this manner, generation of noise during sleep can be extremely effectively prevented. That is, the drive amount of the second fan 36 can be set to an appropriate value according to the heat generation amount of the power supply substrate 32. Further, in the laser printer 1, a first fan 35 for mainly cooling the process unit 7 and the like and a second fan 36 for mainly cooling the power supply substrate 32 are provided separately. Therefore, the second
In controlling the driving amount of the fan 36, there is no need to consider the amount of heat generated by the fixing unit 8 and the like.
It is possible to control the driving amount to be necessary and sufficient for cooling. Therefore, the control of the second fan 36 can be further simplified, the processing speed can be improved, and the noise can be further reduced.

Although the memory board 70 is also a kind of option board in a broad sense, the amount of heat generated by the power supply unit hardly changes even when the memory board 70 is mounted. Therefore, in the laser printer 1, the electrodes 57 a and 57 b are provided only on the option board interface 57, and are not provided on the memory interface 59. In S6, only the presence or absence of the option board 60 is referred to. That is, even if the memory board 70 is mounted, the sleep mode 1 (S9) is executed unless the option board 60 is mounted. Therefore, in the laser printer 1, the second fan 3
6 can be suppressed to a necessary minimum, and the generation of noise can be suppressed very favorably.

That is, the electrodes 57a and 57b and the processing of S6 and the storage area of the ROM 72 storing the processing correspond to the detecting means and the board determining means. In the above-described embodiment, the processing of S7, S9, and S10 and the storage area of the ROM 72 storing the processing and the drive circuit 94 serve as cooling control means, and the second fan 36 and the second fan motor 36a serve as cooling means. The first fan 35 and the first fan 35
The fan motor 35a corresponds to another cooling unit, and the second fan motor 36a corresponds to a drive motor.

It should be noted that the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the gist of the present invention. For example, in the above embodiment, the first fan 35 is stopped in both the sleep modes 1 and 2, but in each sleep mode, the first fan 35 is intermittently operated like the second fan 36 in the sleep mode 2. It may be driven. In this case, the residual heat remaining inside the main body case 2 can be more favorably removed. Further, in the above embodiment, the presence / absence (attachment / non-attachment) of the option board 60 is detected by the electrodes 57a and 57b, but this detection can be performed by other various configurations. For example, the user may operate a switch or the like when the optional board 60 is attached or detached. However, as in the above embodiment, the presence or absence of the option board 60 is automatically detected, and
When controlling the drive amount of the second fan 36 based on the detection result, the drive amount of the second fan 36 can be reliably controlled to the drive amount according to the presence or absence of the option board 60. Therefore, the noise accompanying the driving of the second fan 36 can be reduced more reliably. Alternatively, a predetermined signal may be sent to the option board interface 57, and the presence or absence of the option board 60 may be detected by a response thereto. In this case, the type of the option board 60 mounted on the option board interface 57 can be detected by analyzing the response. Therefore, even when the memory board 70 or the like can be mounted on the option board interface 57, it can be determined whether or not the mounted option board increases heat generation of the power supply board 32.

The present invention can be applied to electronic devices other than the image forming apparatus, such as a personal computer. However, in the image forming apparatus, it is particularly desired to reduce noise during sleep. In the above embodiment, the noise during sleep in the laser printer 1 as the image forming apparatus can be satisfactorily reduced.
The effect of the present invention appears particularly remarkably.

Further, in a so-called electrophotographic printer having a heat fixing device (for example, a fixing unit 8) for heating and fixing a toner image such as a laser printer 1, the outer periphery of the heat fixing device is used for image formation. Needs to be cooled, and relatively loud noise is generated, but almost no noise is generated during sleep. In the above-described embodiment, noise during sleep in the laser printer 1 as an electrophotographic printer can be reduced, so that the effects of the present invention are more remarkably exhibited.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a main part of a configuration of a laser printer according to an embodiment.

FIG. 2 is an upper sectional view of a main part showing the configuration of the laser printer.

FIG. 3 is a rear view illustrating a configuration of the laser printer.

FIG. 4 is a perspective view illustrating a configuration of a control board of the laser printer.

FIG. 5 is an explanatory diagram illustrating a back surface of the laser printer when an optional board is mounted.

FIG. 6 is a block diagram illustrating a configuration of a control system of the laser printer.

FIG. 7 is a schematic diagram illustrating a configuration for detecting the presence or absence of an option board.

FIG. 8 is a flowchart showing a mode switching process by the control system.

FIG. 9 is a time chart showing a driving mode of the fan by the processing.

[Explanation of symbols]

1: laser printer 7: process unit
8: Fixing unit 32: Power supply board 33: Control board 3
5 First fan 35a First fan motor 36 Second fan 3
6a: Second fan motor 57: Optional board interface 57a, 5
7b: electrode 60: option board 71: CPU 72: RO
M 73 RAM 82 DC controller circuit 93 94 Drive circuit

Claims (6)

[Claims] 1. An electronic device to which an optional board as a board to be mounted as required can be mounted, wherein the optional board is removably mounted, and a control unit for executing various controls is provided. A power supply unit for supplying power; cooling means for cooling the power supply unit; and cooling control means for reducing the driving amount of the cooling means when the optional board is not mounted, compared to when the optional board is mounted. Electronic equipment characterized by the above. 2. The apparatus according to claim 1, further comprising detecting means for detecting the mounting of the option board, wherein the cooling control means controls the driving amount based on a detection result of the detecting means. Electronic equipment. 3. The image forming apparatus according to claim 1, further comprising: an image forming unit configured to form an image on the recording medium, wherein the cooling control unit is configured to drive the cooling unit when the image forming unit is not driven, compared to when the image forming unit is driven. 3. The electronic apparatus according to claim 1, wherein a driving amount of the cooling unit is further reduced at least when the optional board is not mounted, at least when the optional board is not mounted, compared to when the optional board is mounted. . 4. The apparatus according to claim 1, further comprising another cooling unit for cooling the image forming unit, wherein the cooling control unit controls only the driving amount of the cooling unit for cooling the power supply unit as described above. The electronic device according to claim 3. 5. The apparatus according to claim 1, further comprising: a board determination unit configured to determine whether the option board increases heat generation of the power supply unit when the option board is mounted. Based on the judgment result of the judging means, when mounting the option board which does not increase the heat generation of the power supply section, it is preferable to reduce the driving amount of the cooling means as compared with when mounting the option board which increases the heat generation of the power supply section. The electronic device according to claim 1, wherein: 6. The cooling device according to claim 1, wherein the cooling means includes: a fan that generates cooling air by rotating the fan; and a drive motor that drives the fan to rotate. Electronics.