JP2000259064A - Heat discharging device and image forming device provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat discharging device making the convection in a duct satisfactorily accelerated, without particularly adopting a fan or the like. SOLUTION: The heat discharging device is provided with the duct 3 penetrating through between a heat source part 1 discharging the heat and a part to be affected by the heat 2. The exhausting port 3a of the duct 3 is opened on the device upper part, and intake ports 3b and 3c is respectively opened in the part below thereof, and on the both side of the heat source part 1. Moreover, on the outer casing section of the heat source 1, a heat insulating member 4 is disposed in the position on the side facing the object part 2, and a communicative hole 5 letting the inside space of the duct 3 on the side opposite thereto, and the ambient space of the heat source 1 in the route of the duct 3 communicated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-dissipating device for preventing heat from being applied to a target portion by removing heat from a heat source portion by utilizing natural convection, and an image provided with the same. The present invention relates to a forming apparatus.

[0002]

2. Description of the Related Art In general, among various electronic equipments, there are many electronic equipments in which a heat source part for discharging heat and a target part affected by the heat are provided in a mixed manner. For example, in an image forming apparatus such as an electrophotographic copying machine or a printer, a fixing unit as a main heat source and a cleaner unit (or a developing unit or the like) affected by heat are provided in a mixed manner in the apparatus. .

In an electronic apparatus having such a structure, for example, the above-described image forming apparatus, the influence of heat discharged from the fixing unit is reduced by arranging the fixing unit and a cleaner unit as far as possible in the apparatus. Consideration is given not to reach departments.

[0004]

However, in recent years, the space and the size of the machine have been reduced, and the positional relationship between the fixing device and the cleaner has been getting closer. As a result, the fixing unit and the cleaner unit cannot be sufficiently separated from each other as in the past, and there is a problem that the toner in the cleaner unit coagulates due to the heat discharged from the fixing unit. It has occurred.

[0005] To solve this problem, conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 5-142911, "a shielding plate forming a ventilation line is provided, and a heat-dissipating fan is used efficiently to use a cleaner unit. Forced air cooling "has been proposed. However, in this remedy, since a fan is used to cool the cleaner portion, other problems such as an increase in power consumption and generation of noise when the fan rotates are caused.

As another prior art, for example, Japanese Patent Publication No. 2626031 discloses an exhaust duct provided so as to pass near the upper portion of a heat fixing device, and an exhaust fan provided at an exhaust port of the exhaust duct. The air inlet of the exhaust duct is located near the image forming process mechanism, and the heat convection and chimney effects obtained when the exhaust duct is partially heated by the heat generated by the heat fixing device, and the air flow effect by the exhaust fan In this case, heat is exhausted to suppress the influence of heat on the image forming process mechanism. Further, in the technique disclosed in the publication, the exhaust fan is operated only at the time of executing image formation, thereby reducing power consumption and exhaust noise.

However, the above-mentioned Japanese Patent No. 2626031
In the technology disclosed in Japanese Patent Application Laid-Open Publication No. H10-209, a part (outer wall) of an exhaust duct is heated from the outside using heat discharged from a heat fixing device, thereby indirectly warming air in the duct. Therefore, there is a problem that natural convection in the duct caused by the temperature difference cannot be sufficiently promoted.

That is, as shown in FIGS. 11 and 12, a duct 54 is disposed between a heat source 51 such as a heat fixing device and two target parts 52 and 53 affected by heat. Is heated by the exhaust heat from the heat source 51 (step), the air in the duct 54 is gradually warmed at that portion. Thus, when the temperature inside the duct 54 gradually increases (step), a certain temperature difference occurs in the duct (near the exhaust port 54a and near the intake port 54b of the duct 54). Due to this temperature difference, the duct 54
In the inside, natural convection is slightly promoted (step).

At this time, in the system in which the air in the duct 54 is indirectly warmed through the air layer in the vicinity and the outer wall of the duct as described above, a sufficient temperature difference cannot be obtained in the duct 54. The natural convection inside is not sufficiently promoted. Therefore, the exhaust heat from the heat source unit 51 stays in the space near the duct 54 and the heat source unit 51, whereby the heat source unit 51
Then, the ambient temperature near the duct 54 starts to rise (step). When the retention of the exhaust heat further progresses, the target portion 5 is finally reached.
The influence of the temperature rise will affect 2 and 53 (step).

Therefore, according to the technique disclosed in Japanese Patent Publication No. 2626031, the exhaust fan is an essential component in order to sufficiently promote the convection in the duct, and the exhaust fan is required to obtain a sufficient heat exhaust effect. It is necessary to rotate at some high speed. Therefore, the increase in power consumption and the problem of noise have not been sufficiently solved.

Further, in addition to the technology disclosed in the above publication, for example, as disclosed in Japanese Patent Application Laid-Open No. 5-2308, "a heat shut-off shutter is provided between a heat fixing device and an image carrier so as to be openable and closable. Specifically, FIG.
As shown in FIGS. 3 (a) and 3 (b), the solenoid 55 is turned on / off.
Partition plate 5 that opens and closes when turned off (ON / OFF)
6 is provided between the photoreceptor unit 57 and the heat fixing device 58, and when the solenoid 55 is off (OFF), the partition plate 56 is closed, and the sheet is conveyed from the photoreceptor unit 57 to the heat fixing device 58. Only when the solenoid 55 is turned ON, the partition plate 56 is opened, so that the heat discharged from the heat fixing device 58 is prevented from being transmitted to the photoconductor unit 57 side.

However, according to the technique disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 5-2308, even when the solenoid 55 is turned off and the partition plate 56 is closed while the heat fixing device 58 is energized and in a standby state, The temperature of the partition plate 56 itself rises with time due to the heat discharged from the heat fixing device 58, and as a result, the radiation heat from the partition plate 56 adversely affects the photoconductor unit 57. Also, while the partition plate 56 is closed, the temperature in the vicinity of the heat fixing device 58 rises excessively, so that the retained heat flows into the photoreceptor unit 57 when the partition plate 56 is opened, and exerts an adverse effect. I will.

[0013]

In the heat exhaust device according to the present invention, the heat exhaust device is provided between the heat source portion for discharging heat and the target portion affected by the heat, and the exhaust port thereof is higher than the intake port. And a heat insulating member disposed on an outer portion of the heat source portion located on a side facing the target portion, and a duct of the duct on a side opposite to a position where the heat insulating member is disposed. A configuration is adopted in which a communication port for communicating the internal space and the space near the heat source section is provided in the path of the duct.

According to the heat discharging device having the above-described structure, the heat discharged from the heat source portion is guided to the side opposite to the target portion by the heat discharge suppressing action of the heat insulating member provided at the outer portion. Further, the heat thus induced is taken into the duct directly from the communication port in the duct path together with the air near the heat source. Thus, heat transfer from the heat source to the target portion is suppressed, and natural convection in the duct is promoted by taking in heat induced by the heat insulating member.

In another heat exhaust device according to the present invention, the heat exhaust device is provided between the heat source portion for discharging heat and the target portion affected by the heat, and the exhaust port is disposed higher than the intake port. Duct, and a heat insulating member disposed on the outer portion of the heat source portion located on the side facing the target portion, and in the vicinity of the heat source portion and on the side opposite to the disposition position of the heat insulating member. And a heat recovery means having high thermal conductivity disposed on one side facing the inside of the duct and on the other side facing the heat source portion.

According to the heat discharging device having the above-described structure, the heat discharged from the heat source portion is guided to the opposite side of the target portion by the heat discharge suppressing action of the heat insulating member provided at the outer portion. Further, the heat thus induced is recovered by the heat recovery means, and the recovered heat is supplied into the duct by the high thermal conductivity of the heat recovery means. This allows
Heat transfer from the heat source to the target is suppressed,
Recovery of heat induced by the heat insulating member promotes natural convection in the duct.

Further, in another heat exhaust device according to the present invention, the heat exhaust device is provided between the heat source portion for discharging heat and the target portion affected by the heat, and the exhaust port is disposed higher than the intake port. And a shutter mechanism for shutting off the space between the heat source unit and the target unit by closing the partition plate, having a closed duct, and a shutter plate that can be opened and closed. And a configuration in which an intake port of the duct is arranged near the partition plate.

According to the heat exhaust device having the above configuration, by closing the partition plate of the shutter mechanism, heat transfer from the heat source to the target portion is blocked, and the heat blocked there is divided by the partition. It is taken in from the air inlet of the duct together with the air near the plate. As a result, natural convection in the duct is promoted, and a rise in the temperature of the partition plate itself and a rise in the temperature of the space in the vicinity thereof are prevented.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a first embodiment of a heat exhaust device according to the present invention. In FIG. 1, a heat source unit 1 discharges (discharges) heat, such as a unit having a heat source such as a heater therein, a unit having heat generation during operation, or a unit generating heat itself. It is. On the other hand, the target portion 2 may be affected by heat, such as a component that may malfunction due to heat received from the outside, a component that handles a material that is weak to heat, or a component that has a component that is deteriorated by heat. Is to receive.

A duct 3 is provided between the heat source 1 and the object 2.
Has been passed. This duct 3 is arranged so as to block between the heat source unit 1 and the target unit 2 in the depth direction of the drawing. Further, one end of the duct 3 is disposed so as to extend substantially vertically, and the extended end is opened as an exhaust port 3a in the upper part of the apparatus. On the other hand, the other end of the duct 3 is arranged and formed in a substantially gate shape, and each end is opened as intake ports 3b and 3c on both sides of the heat source unit 1. Thereby, the duct 3
Is disposed higher than the two intake ports 3b and 3c.

Further, a heat insulating member 4 such as urethane foam is provided on an outer portion of the heat source section 1. The heat insulating member 4 is disposed on the side facing the target portion 2 and outside the outer periphery of the heat source portion 1 so as to have a substantially L-shaped cross section.

On the other hand, a communication port 5 is provided in the path of the duct 3. The communication port 5 is formed in a part of the duct 3 so as to communicate the internal space of the duct 3 with the space near the heat source 1. The communication port 5 is provided on the opposite side of the position where the heat insulating member 4 is provided. The communication port 5 may be formed in a slit shape continuous in the depth direction of the drawing, or may be formed in a plurality at predetermined intervals along the same direction. In addition,
The dashed line in the figure indicates the outer part of the heat exhaust device, and the heat source unit 1
Arrows in the vicinity and in the duct 3 indicate the flow of air (heat). Reference numerals 13a and 13b in the drawing denote a transport roller and a transport guide that form a paper transport path when the target section 2 is an image forming unit and the heat source section 1 is a fixing device.

In the heat exhaust device having the above structure, the heat exhausted from the heat source section 1 is guided to the opposite side of the target section 2 by the heat exhausting action of the heat insulating member 4 provided on the outer portion thereof. . Further, the heat thus induced is taken into the duct 3 directly from the communication port 5 in the duct 3 along with the air near the heat source 1. Thereby, the heat source unit 1
The heat transfer from the heat transfer member to the target portion 2 is suppressed, and the air in the duct 3 is efficiently heated by taking in the heat induced by the heat insulating member 4. Therefore, a sufficient temperature difference can be provided in the duct 3 to promote natural convection. As a result, it is possible to efficiently release the heat discharged from the heat source unit 1 to the outside of the device while preventing the heat discharged from the heat source unit 1 from staying in the vicinity thereof while preventing the direct heat from the heat source unit 1 from being affected by the heat insulating member 4. .

In the first embodiment, the heat insulating member 4 is provided on the outer side of the heat source section 1. However, as shown in FIG. 4 may be provided.

FIG. 3 is a schematic configuration diagram showing a second embodiment of the heat exhaust device according to the present invention. In the second embodiment, the communication port 5 is different from the first embodiment.
Instead of heat sinks 6a and 6b as heat recovery means
The feature is that it is provided. Each heat sink 6a, 6
b has a high thermal conductivity at least as compared to the duct body in terms of material, structure, or material and structure.

Specifically, for example, when the duct 3 is made of iron, the heat sinks 6a and 6b are made of aluminum, copper or the like having a thermal conductivity several times higher than that of the iron. , 6b are made of the same material, the heat sinks 6a, 6b are formed into a fin structure to increase the surface area (heat transfer area) so that the heat conductivity of the heat sinks 6a, 6b is higher than that of the duct body. I do.

The heat sinks 6a and 6b are arranged in a substantially L-shape near the heat source 1 and on the side opposite to the position where the heat insulating member 4 is provided. In addition, the heat sinks 6a, 6
b is incorporated in an opening provided in a part of the duct 3 on the side facing the heat source 1. Further, each of the heat sinks 6 a and 6 b is arranged so that one of them faces the inside of the duct 3 and the other faces the heat source unit 1.
That is, each of the heat sinks 6 a and 6 b is in a state where one of the heat sinks 6 a and 6 b contacts the internal space of the duct 3 and the other contacts the space between the heat sources 1.

In the heat-dissipating device having the above-described structure, heat discharged from the heat source unit 1 is guided to the opposite side of the target unit 2 by the heat-dissipating effect of the heat-insulating member 4 provided on the outer part. . In addition, the heat thus induced is recovered (absorbed) by the heat sinks 6a and 6b, and the recovered heat is supplied into the duct 3 by the high heat conductivity of the heat sinks 6a and 6b themselves. Thereby, heat transfer from the heat source unit 1 to the target unit 2 is suppressed, and
The heat in the duct 3 is efficiently heated by the heat guided by the heat insulating member 4 and recovered by the heat sinks 6a and 6b. Therefore, a sufficient temperature difference can be provided in the duct 3 to promote natural convection. as a result,
The heat discharged from the heat source unit 1 can be efficiently released to the outside of the apparatus without staying in the vicinity of the heat source unit 1 while preventing the influence of the direct heat from the heat source unit 1 by the heat insulating member 4.

In the second embodiment, the heat recovery means (heat sinks 6a and 6b) are provided separately from the duct 3. However, other than this, for example, the heat recovery means of the duct 3 facing the heat source unit 1 may be provided. It is also possible to form heat recovery means integrally with the duct 3 by shaping the surface into a corrugated shape and giving a high thermal conductivity to a part of the duct 3 by increasing the surface area (heat transfer area) accompanying this. It is.

FIG. 4 is a schematic configuration diagram showing a third embodiment of the heat exhaust device according to the present invention. The third embodiment is characterized in that the first embodiment and the second embodiment are combined. That is, the heat insulating member 4 is provided on the outer surface of the heat source unit 1 (outer surface of the outer surface in the illustrated example) on the side facing the target unit 2. Further, a communication port 5 is provided in the path of the duct 3 as in the first embodiment,
In the vicinity, heat sinks 6a and 6b as heat recovery means are provided similarly to the second embodiment.

In the heat exhaust device having the above-described structure, the heat exhausted from the heat source unit 1 is guided to the opposite side of the target unit 2 by the heat exhausting action of the heat insulating member 4 provided at the outer part thereof. . In addition, the heat thus induced is efficiently taken into the duct 3 by the synergistic effect of taking in air from the communication port 5 in the duct 3 and heat recovery by the heat sinks 6a and 6b. As a result, a larger temperature difference is generated inside the duct 3, so that natural convection in the duct 3 can be further promoted.

In the third embodiment, the communication port 5 is provided with a part of the duct 3 being opened. In addition, a part of the heat sinks 6a and 6b is opened. The communication port may be provided in the state.

FIG. 5 is a schematic configuration diagram showing a fourth embodiment of the heat exhaust device according to the present invention. In FIG. 5, a duct 3 is provided between a heat source unit 1 that discharges heat and a target unit 2 that is affected by heat. The exhaust port 3a of the duct 3 is open at the top of the apparatus, and the intake ports 3b and 3c are open on both sides of the heat source unit 1. Such a configuration is the same as the device configuration of the first embodiment. In addition, in the fourth embodiment, a shutter mechanism 7 is provided between the heat source unit 1 and the target unit 2.

The shutter mechanism 7 has a solenoid (preferably a keep solenoid) 8 serving as a drive source, and a partition plate 9 which opens and closes according to the drive state of the solenoid 8. The upper end of the partition plate 9 is connected to the plunger of the solenoid 8, and is supported so as to be movable in the vertical direction in the figure by the reciprocating operation of the plunger. On the other hand, of the two intake ports 3 b and 3 c of the duct 3, one (the right side in the figure) of the intake port 3 c is arranged near the partition plate 9.

In the heat exhaust device having the above configuration, the shutter mechanism 7 operates as follows. That is, when the solenoid 8 is turned off (OFF), the partition plate 9 is closed as shown in the figure, thereby blocking the space between the heat source unit 1 and the target unit 2. When the solenoid 8 is turned on (ON) in this state, the partition plate 9 is turned on.
Is opened, whereby the space between the heat source unit 1 and the target unit 2 is opened.

Here, by closing the partition plate 9 as described above, the heat transfer from the heat source unit 1 to the target unit 2 is blocked, and the heat blocked there is reduced to the vicinity of the partition plate 9. It is taken into the duct 3 through the air inlet 3 together with the air. Thereby, since the air in the duct 3 is efficiently heated, a sufficient temperature difference is generated in the duct 3 and natural convection is promoted. Further, the promotion of natural convection in the duct 3 prevents the temperature of the partition plate 9 itself and the temperature of the space near the partition plate 9 from rising, so that the radiant heat from the partition plate 9 adversely affects the target portion 2 and the partition. An adverse effect on the target portion 2 due to the flow of heat when the plate 9 is opened can be avoided.

FIG. 6 is a schematic configuration diagram showing a fifth embodiment of the heat exhaust device according to the present invention. The fifth embodiment is characterized in that the first embodiment and the fourth embodiment are combined. That is, the heat insulating member 4 is provided on the outer surface of the heat source unit 1 (outer surface of the outer surface in the illustrated example) on the side facing the target unit 2. A communication port 5 is provided in the path of the duct 3 as in the first embodiment.
Further, a shutter mechanism 7 having a partition plate 9 is provided between the heat source unit 1 and the target unit 2, and an intake port 3 c of the duct 3 is arranged near the partition plate 9.

In the heat exhaust device having the above configuration, in addition to the same operation and effect as the first embodiment and the same operation and effect as the fourth embodiment, the intake of air from the communication port 5 and the intake port 3c Due to the synergistic effect of taking in air from the air, a larger temperature difference occurs in the duct 3, so that natural convection in the duct 3 can be further promoted.

FIG. 7 is a schematic configuration diagram showing a sixth embodiment of the heat exhaust device according to the present invention. The sixth embodiment is characterized in that the second embodiment and the fourth embodiment are combined. That is, the heat insulating member 4 is provided on the outer surface of the heat source unit 1 (outer surface of the outer surface in the illustrated example) on the side facing the target unit 2. Further, heat sinks 6a and 6b as heat recovery means are provided near the heat source unit 1 and on the side opposite to the position where the heat insulating member 4 is provided. further,
A shutter mechanism 7 having a partition plate 9 is provided between the heat source unit 1 and the target unit 2, and an intake port 3 c of the duct 3 is arranged near the partition plate 9.

In the heat exhaust device having the above-described configuration, in addition to the same operation and effect as the first embodiment and the same operation and effect as the fourth embodiment, heat recovery by the heat sinks 6a and 6b and the heat from the intake port 3c are performed. Due to the synergistic effect of taking in the air (air near the partition plate 9), a larger temperature difference occurs in the duct 3, so that natural convection in the duct 3 can be further promoted.

Further, in the heat discharging device shown in FIG. 7, a communication port 5 similar to the second embodiment is added to the path of the duct 3, that is, the third embodiment and the fourth embodiment are combined. If the configuration is adopted, the heat sink 6
In addition to the synergistic effect of heat recovery by the a and 6b and the intake of air from the intake port 3c, the exhaust heat effect by the intake of air from the communication port 5 is also obtained, so that natural convection in the duct 3 is further promoted. be able to.

FIG. 8 is a schematic configuration diagram showing a seventh embodiment of the heat exhaust device according to the present invention. In the seventh embodiment, in comparison with the fifth embodiment, the lower end portion of the partition plate 9 comes into contact with the outside air in a state where the partition plate 9 of the shutter mechanism 7 is closed (the solenoid 8 is turned off). There is a feature in that the configuration is made as described above.

More specifically, a partition receiving cover 10 having an inverted concave cross section is provided at the lower part of the apparatus. The partition receiving cover 10 is arranged at a position facing the shutter mechanism 7 in the vertical direction in the figure. In addition, a slit-like hole through which the partition plate 9 can be freely inserted and removed is formed at the upper end of the partition receiving cover 10, and the lower end of the partition plate 9 is inserted into the hole when the partition plate 9 is closed. It has become. Furthermore, one end (opening) of the second duct 11 is arranged in the lower space of the partition receiving cover 10 so as to face this. The other end (not shown) of the second duct 11 is arranged so as to face the outside of the device.

In the heat exhaust device having the above structure, the internal space of the partition receiving cover 10 always communicates with the outside air (normal temperature air outside the device) through the second duct 11 facing the partition receiving cover 10. 8 drives the partition 9
Is closed, the lower end of the partition plate 9 is inserted into the hole of the partition receiving cover 10 and directly comes into contact with the outside air. This allows the partition plate 9 itself to be cooled by contact with the outside air in a state where heat transfer from the heat source unit 1 to the target unit 2 is blocked by the partition plate 9, so that the temperature rise of the partition plate 9 is further reduced. It can be effectively prevented.

In the seventh embodiment, the characteristic portion has been described in comparison with the fifth embodiment. However, such a characteristic portion is described in any of the fourth to sixth embodiments. Applicable.

FIG. 9 is a schematic configuration diagram showing an eighth embodiment of the heat exhaust device according to the present invention. The eighth embodiment is characterized in that a fan 12 is provided inside the duct 3 in comparison with the first embodiment (FIG. 1).

The fan 12 is a very small, for example, axial fan. The fan 12 is incorporated downstream of the junction of the air taken in from the intake ports 3b and 3c and in the middle of the duct 3 leading to the exhaust port 3a. As a specific assembling procedure, for example, the duct 3 is divided corresponding to the mounting position of the fan 12, and the fan 12 is mounted on a hollow connecting member capable of connecting each divided portion. The fan 12 can be accommodated in the duct 3 by connecting and integrating the fan 12 with the connecting member.

In the heat exhaust device having the above structure, the convection in the duct 3 is greatly promoted by the rotation of the fan 12 provided in the duct 3. At this time,
Since natural convection in the duct 3 is promoted by heat induction by the heat insulating member 4 and intake of air from the communication port 8, convection in the duct 3 is necessary and sufficient even when the fan 12 is rotated at an extremely low speed. Can be promoted. Also,
Since the fan 12 is provided in the duct 3, the fan 12
Exhaust noise is hardly leaked out, and a sufficient heat exhausting effect can be obtained only by rotating the fan 12 at an extremely low speed. This makes it possible to simultaneously reduce power consumption and exhaust noise when the fan 12 is rotated.

In the eighth embodiment, the characteristic portions have been described in comparison with the first embodiment. However, such characteristic portions are not described in any of the first to seventh embodiments. Applicable.

FIG. 10 is a schematic view showing an example of the configuration of an image forming apparatus provided with a heat discharging device according to the present invention. Here, the configuration of the image forming apparatus provided with the heat discharging device of the fifth embodiment is exemplified. are doing. The illustrated image forming apparatus has a fixing device 14 as a heat source for discharging heat. Also,
The target section affected by the heat includes a control board (printed circuit board or the like) 15 constituting various control circuits, and an image forming unit (photosensitive unit) 18 including a developing unit 16 and a photosensitive body 17. ing.

The fixing unit 14 fixes (fixes) the toner image transferred to the sheet by the image forming unit 18 on the sheet by melting the sheet by a heating and pressing action using a roller. A heater or the like serving as a heat source is provided inside. In addition, various electronic components are mounted on the control board 15, including electronic components that are vulnerable to heat and electronic devices that may malfunction due to heat. On the other hand, the developing device 16 of the image forming unit 18 contains toner that is easily solidified by heat. When the toner in the developing device 16 solidifies, uneven development occurs, which causes deterioration in the quality of an output image. Although not shown in the drawings, the cleaner unit that cleans the toner remaining in the image forming unit 18 at the time of image transfer handles the toner.

By providing the heat insulating member 4 and the communication port 5 to such an image forming apparatus (for example, an electrophotographic copying machine, a printer, etc.) as in the fifth embodiment, a fan or the like can be used. However, natural convection in the duct 3 can be promoted, and by providing the shutter mechanism 7 in combination with the duct 3, heat transfer from the fixing device 14 to the image forming unit 18 can be suppressed while the partition plate 9
And an increase in the temperature of the space in the vicinity thereof can be prevented.

As a result, it is possible to effectively prevent the influence of the heat discharged from the fixing unit 14 from affecting the control board 15 and the developing unit 16 and the like. Can be avoided.
As a result, the operation reliability of the image forming apparatus can be improved.

[0054]

As described above, according to the heat discharging device of the present invention, the heat discharged from the heat source portion is opposed to the target portion by the heat discharging suppressing action of the heat insulating member provided at the outer portion. Side, and the induced heat is taken into the duct directly from the communication port in the duct path together with the air near the heat source, thereby suppressing heat transfer from the heat source to the target part. In addition, natural convection in the duct is promoted by taking in heat induced by the heat insulating member. Thus, the heat discharged from the heat source unit can be released from the exhaust port of the duct without staying in the space near the heat source unit while preventing the effect of the direct heat from the heat source unit by the heat insulating member. As a result, even without using a fan or the like, it is possible to effectively prevent the thermal influence on the target portion.

Further, according to another heat discharging device of the present invention, the heat discharged from the heat source portion is guided to the opposite side of the target portion by the heat discharging suppressing action of the heat insulating member provided on the outer portion. Further, the induced heat is recovered by the heat recovery means and efficiently supplied into the duct, so that the heat transfer from the heat source portion to the target portion is suppressed, and the heat induced by the heat insulating member. The natural convection in the duct is promoted by the recovery. Thus, the heat discharged from the heat source unit can be released from the exhaust port of the duct without staying in the space near the heat source unit while preventing the effect of the direct heat from the heat source unit by the heat insulating member. As a result, even without using a fan or the like, it is possible to effectively prevent the thermal influence on the target portion.

Further, according to another heat discharging device of the present invention, by closing the partition plate of the shutter mechanism, heat transfer from the heat source to the target portion is blocked, and the heat blocked there is blocked. Is taken in from the air inlet of the duct together with the air near the partition plate, thereby promoting natural convection in the duct. As a result, it is possible to prevent a temperature rise of the partition plate itself and a temperature rise of a space in the vicinity thereof,
It is possible to avoid the adverse effect on the target portion due to the radiant heat from the partition plate and the negative effect on the target portion due to the flow of heat when the partition plate is opened.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of a heat exhaust device according to the present invention.

FIG. 2 is a schematic configuration diagram illustrating a modification of the first embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing a second embodiment of a heat exhaust device according to the present invention.

FIG. 4 is a schematic configuration diagram illustrating a third embodiment of a heat exhaust device according to the present invention.

FIG. 5 is a schematic configuration diagram showing a fourth embodiment of a heat exhaust device according to the present invention.

FIG. 6 is a schematic configuration diagram showing a fifth embodiment of a heat exhaust device according to the present invention.

FIG. 7 is a schematic configuration diagram showing a sixth embodiment of a heat exhaust device according to the present invention.

FIG. 8 is a schematic configuration diagram showing a seventh embodiment of a heat exhaust device according to the present invention.

FIG. 9 is a schematic configuration diagram showing an eighth embodiment of a heat exhaust device according to the present invention.

FIG. 10 is a schematic diagram illustrating a configuration example of an image forming apparatus including a heat exhaust device according to the present invention.

FIG. 11 is a schematic diagram illustrating a conventional technique.

FIG. 12 is a flowchart showing a flow of exhaust heat according to the related art.

FIG. 13 is a diagram illustrating another conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Heat source part, 2 ... Target part, 3 ... Duct, 4 ... Heat insulation member, 5 ... Communication port, 6a, 6b ... Heat sink (heat recovery means), 7 ... Shutter mechanism, 9 ... Partition plate, 10 ... Partition receiver Cover, 11: second duct, 12: fan, 1
4: fixing device, 15: control board, 16: developing device, 17: photoconductor, 18: image forming unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H027 JA11 JB12 JB14 JB15 JB16 JB27 JB29 JC06 JC08 2H071 EA00 9A001 BB06 JZ35

Claims (10)

[Claims] 1. A duct provided between a heat source part for discharging heat and a target part affected by the heat, and an exhaust port thereof is disposed higher than an intake port, and a duct and a surface thereof. And a heat insulating member disposed on the outer side of the heat source portion, which is located on the side where the heat source portion is provided. The internal space of the duct communicates with the space near the heat source portion on the side opposite to the position where the heat insulating member is disposed. A heat exhaust device characterized in that a communication port is provided in a path of the duct. 2. A duct which is provided between a heat source part for discharging heat and a target part affected by the heat and whose exhaust port is arranged higher than an intake port, A heat insulating member disposed on an outer side of the heat source portion and located near the heat source portion, and provided near the heat source portion and on a side opposite to the position where the heat insulating member is disposed, and one of the surfaces is provided in the duct. And a heat recovery unit having a high thermal conductivity disposed on the other side facing the heat source unit. 3. A communication port for communicating an internal space of the duct with a space in the vicinity of the heat source portion on a side opposite to a position where the heat insulating member is provided, is provided in a path of the duct. The heat removal device according to claim 2. 4. A duct, which is provided between a heat source part for discharging heat and a target part affected by heat, and whose exhaust port is disposed higher than an intake port, comprises a partition plate which can be opened and closed. A shutter mechanism that shuts off a space between the heat source unit and the target portion by closing the partition plate, and a shutter near the partition plate of the shutter mechanism. A heat exhaust device comprising an intake port. 5. An internal space of the duct, comprising: a heat insulating member disposed on a side facing the target portion and disposed on an outer portion of the heat source portion; and an opposite space from a position where the heat insulating member is disposed. The heat exhaust device according to claim 4, wherein a communication port that communicates with a space near the heat source unit is provided in a path of the duct. 6. A heat insulating member disposed on an outer portion of the heat source portion located on a side facing the target portion, and in a vicinity of the heat source portion and on a side opposite to a position where the heat insulating member is disposed. The heat exhaust device according to claim 4, further comprising: a heat recovery means having high thermal conductivity, one of which is provided inside the duct, and the other is provided facing the heat source portion. . 7. A communication port for communicating between an internal space of the duct and a space in the vicinity of the heat source on a side opposite to a position where the heat insulating member is provided, is provided in a path of the duct. The heat removal device according to claim 6. 8. The shutter mechanism according to claim 4, wherein a part of the partition plate comes into contact with outside air when the partition plate of the shutter mechanism is closed. A heat removal device according to item 1. 9. The heat exhaust device according to claim 1, wherein a fan is provided inside the duct. 10. The heat discharging device according to claim 1, wherein the heat source unit is a fixing unit, and the target unit is an image forming unit including at least a developing unit. An image forming apparatus comprising: