JP4738644B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a copying machine or a laser beam printer.
[0002]
[Prior art]
Generally, in image forming apparatuses such as copying machines, printers, and facsimiles that form an image on a recording material using toner, the recording material such as paper or an OHP sheet is made by using electrostatic powder or chemical dispersion force. To form an unfixed image. Since this unfixed image adheres to the recording material only with a weak force, it is necessary to prevent the recording material image from changing or moving. Therefore, such an image forming apparatus is provided with a fixing process for fixing an unfixed image made of powder onto a recording material. In this fixing process, the fixing device melts and presses a powder such as toner on the recording material to firmly fix the powder and the recording material.
[0003]
FIG. 3 shows an example of a conventional fixing device.
[0004]
As shown in FIG. 3, the fixing device 10 includes a fixing roller 11 that includes a heat source therein, a pressure roller 13 that is disposed facing the fixing roller 11 and presses the recording material P against the fixing roller 11 to fix the recording material P. It has.
[0005]
The fixing roller 11 has a halogen rod lamp 12 disposed therein as a heat source.
[0006]
Through a process section (hereinafter collectively referred to as an image forming process section 1) that has a process such as development and transfer and attaches toner to the recording material P to form an unfixed image on the recording material P, the surface of the toner The recording material P attached to the toner passes through the conveyance path 4 and is heated and pressed by the fixing device 10.
[0007]
As a result, the toner image is fixed on the surface, and then the recording material P is discharged to the outside of the image forming apparatus main body to complete the image formation.
[0008]
[Problems to be solved by the invention]
Incidentally, the fixing roller 11 is naturally deprived of heat by the passage of the recording material P. For this reason, the fixing roller 11 must be kept at a temperature so as not to fall below the fixable temperature before the next recording material P passes.
[0009]
In addition, with the recent increase in output and production of image forming apparatuses, the time for the recording material P to pass through the fixing roller 11 is shortened, and the interval until the next recording material P passes through the fixing roller 11 is increased. It is getting shorter. This means that the fixing roller 11 must be kept at a high temperature for a long time.
[0010]
If the fixing roller 11 is held at a high temperature for a long time, the temperature of the fixing device 10 rises. When the temperature of the fixing device 10 rises, the units (hereinafter, the surrounding units 2 and 3) that are devices around are also affected and the temperature rises. In particular, when a developing device is arranged as the peripheral unit 2, the developing performance deteriorates when the developing device becomes high temperature.
[0011]
Conventionally, the surrounding air 6 around the fixing device is blown by using a blower (not shown) such as a fan in order to avoid the high temperature of the surrounding units 2 and 3 due to the temperature rise of the fixing device 10. .
[0012]
However, when the ambient air 6 around the fixing device 10 is blown, the fixing roller 11 itself loses its temperature, and the fixing possible temperature cannot be maintained, or excessive power is required to maintain the temperature.
[0013]
SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of reducing the temperature increase of surrounding units due to the temperature increase of the fixing device and suppressing power consumption required by the fixing device.
[0014]
[Means for Solving the Problems]
In order to solve the above problems, the present invention has the following configuration. That is, an image forming process unit that forms an unfixed image on a recording material, and a fixing device that fixes the unfixed image on the recording material by heating, at least a part of the image forming process unit is In the image forming apparatus which is a peripheral unit arranged around the fixing device,
A first cover that covers a part of the fixing device and is formed over the entire length of the fixing device, and a gap that covers the first cover and is formed over the entire length of the first cover. , A second cover in which a sealed air layer is formed in the gap, and an air inlet for forming the air outside the apparatus main body and the outside of the apparatus main body formed between the second cover and the surrounding unit. And an air passage provided with an exhaust port for exhausting air, and a partition member provided in the second cover for confining air in the air passage between the second cover and the surrounding unit.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0019]
(First embodiment)
First, a first embodiment of the present invention will be described.
[0020]
FIG. 1 is a diagram showing a schematic configuration of an image forming apparatus to which the present invention is applied.
[0021]
In such an image forming apparatus, the image forming process unit 1 forms an unfixed image on the recording material P, and the fixing device 10 heats the recording material P carrying the unfixed image to determine the unfixed image. The image is fixed on the recording material P.
[0022]
The image forming process unit 1 has a peripheral unit 2 as a unit. Further, as an apparatus for an image forming process disposed around the fixing device 10, the image forming device has a peripheral unit 3 as a unit above the fixing device 10.
[0023]
Although not shown in the present embodiment, the image forming process unit 1 includes a latent image carrier such as a photosensitive drum carrying a latent image, a charging unit such as a charger for charging the latent image carrier, Exposure means such as a laser scanner unit for performing exposure processing on the latent image carrier, development means such as a developing device for visualizing the latent image as a developer image, and a developer image on the latent image carrier by the development means It has process equipment such as transfer means for transferring to the recording material P. In the present embodiment, the peripheral unit 2 corresponds to a developing unit.
[0024]
Here, features of the present embodiment will be described.
[0025]
As shown in FIG. 1, the image forming apparatus according to the present exemplary embodiment includes a first cover 15 that covers an upper portion of the fixing device 10.
[0026]
The second cover 14 is disposed so as to cover the first cover 15, and the two covers are sealed so that an air layer 16 is formed between the first cover 15 and the second cover 14. In the present embodiment, the first cover and the second cover cover the entire longitudinal direction of the fixing device 10.
[0027]
Further, the second cover 14 is disposed in the vicinity of the peripheral unit 2 and the main body frame 5, and partition ribs 17 and 18 are disposed as partition members for confining the ambient air 7 between the second cover 14 and the peripheral unit 2. Yes.
[0028]
The partition ribs 17 and 18 described above are arranged in the entire longitudinal direction of the fixing device 10 so that the ambient air 7 does not escape to other parts.
[0029]
The frame 5 is provided with an exhaust port 19 for discharging the ambient air 7 out of the main body of the image forming apparatus. The exhaust port 19 has at least one or more openings.
[0030]
Further, an intake port 20 is disposed on the front frame (not shown) of the unit so as to correspond to the exhaust port 19. The intake port 20 has at least one or more openings and is disposed at a position where only the ambient air 7 flows.
[0031]
By providing the first cover 15, the second cover 14, and the air layer 16 having a low thermal conductivity, the surrounding units 2 and 3 do not directly receive the temperature rise in the fixing device 10.
[0032]
The heat from the fixing device 10 transmitted to the second cover heats the ambient air 7, but is discharged out of the machine through the exhaust port 19, thereby preventing the ambient unit 2 and 3 from rising in temperature due to the ambient air 7. be able to.
[0033]
(Second embodiment)
Next, a second embodiment of the present invention will be described. In addition, about the structure similar to 1st embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
[0034]
In the present embodiment, even when the temperature rise of the surrounding units 2 and 3 exceeds the target value even by the configuration of the first embodiment described above, the surrounding ribs are confined by the partition ribs 17 and 18, as shown in FIG. In order to flow the ambient air 7 positively, a blower means 21 such as a fan is provided.
[0035]
In this way, by causing the ambient air 7 to flow positively by the air blowing means 21, the temperature rise of the surrounding units 2 and 3 can be prevented.
[0036]
Here, heat from the surface of the second cover 14 is taken away by the air blowing means 21. However, the heat transfer can be delayed by the heat insulating effect of the second cover, the air layer 16, and the first cover 15, and the fixing device 10 is hardly affected by the blowing of the blowing unit 21.
[0037]
Further, since the surrounding air 7 is confined by arranging the partition ribs 17 and 18, the flow of the surrounding air 7 can be generated at a position where the fixing device 10 is not affected by the blowing means 21. It is hardly affected by the air blow of the air blowing means 21.
[0038]
As described above, the temperature reduction of the fixing device 10 by the blower unit 21, that is, the temperature of the fixing roller 11 is not lost, and the increase in power consumption due to the provision of the blower unit 21 can be minimized.
[0039]
In this embodiment, this air layer was made into the heat insulation layer by providing an air layer between the 1st cover and the 2nd cover. An individual heat insulator is conceivable as the heat insulating layer, but the cost increases accordingly, and therefore air without cost is the best.
[0040]
Therefore, as described above, in this embodiment, it is possible to solve the problem that the temperature increase of the surrounding units 2 and 3 exceeds the target value.
[0041]
In the present embodiment, the materials of the first cover and the second cover are not mentioned, but the material of each cover may be metal or plastic, and is not specified. However, it is clear that the one with low thermal conductivity is good, and the material should be determined in consideration of the cost balance.
[0042]
In the first embodiment or the second embodiment, the partition ribs 17 and 18 are disposed on the second cover as shown in FIGS. 1 and 2, but the ambient air 7 does not cool the fixing device 10. Since it suffices to be confined at the position, a partition rib for the purpose of confining the ambient air 7 may be provided in the peripheral unit.
[0043]
Furthermore, the material of the partition ribs 17 and 18 is not specified, and may be, for example, an elastic body.
[0044]
In the first embodiment or the second embodiment, as shown in FIGS. 1 and 2, the exhaust port 19 is disposed in the frame 5 and the intake port 20 is disposed in the front frame (not shown). As long as the enclosed ambient air 7 flows, it may be disposed anywhere.
[0045]
Furthermore, in the first embodiment or the second embodiment, the roller fixing device is exemplified as the fixing device, but the present invention is not limited to this, and may be, for example, a belt-type fixing device. The same effect can be obtained by applying the present invention to the fixing device.
[0046]
In the first embodiment or the second embodiment, the halogen rod heater is exemplified as the heat source of the fixing device. However, the present invention is not limited to this. For example, the heater uses a nichrome wire. The same effect can be obtained by applying the present invention to various heating type fixing devices.
[0047]
【The invention's effect】
As described above, according to the first invention of the present application, a predetermined gap is provided between the first cover and the second cover, and the first cover and the second cover are sealed to The air layer formed in the gap cuts off heat from the fixing device to the devices around the fixing device, so that the temperature rise of the surrounding units due to the temperature rise of the fixing device is reduced, and the fixing device Power consumption required can be suppressed, and an inexpensive device can be provided by using an air layer.
[0048]
According to the fourth invention of the present application, a predetermined gap is provided between the first cover and the second cover, and the gap is formed by sealing the first cover and the second cover. The air layer shields heat from the fixing device to the devices around the fixing device, and in the space between the second cover and the devices arranged around the second cover. Since air from the outside of the image forming apparatus is sucked from the air inlet and air in the space is exhausted to the outside from the air outlet, the temperature of the surrounding units is effectively increased due to the temperature rise of the fixing device. As well as reducing the rise, it is possible to suppress the power consumption required by the fixing device.
[0049]
Further, according to the fifth invention of the present application, a predetermined gap is provided between the first cover and the second cover, and the gap is formed by sealing the first cover and the second cover. The air layer shields heat from the fixing device to the devices around the fixing device, and in the space between the second cover and the devices arranged around the second cover. Air from the outside of the image forming apparatus is sucked from the air inlet through the air passage by the partition member, and the air in the space is exhausted from the air outlet to the outside through the air passage. While reducing the temperature rise of the surrounding units due to the temperature rise of the fixing device, it is possible to suppress the power consumption required by the fixing device.
[0050]
Further, according to the sixth invention of the present application, a predetermined gap is provided between the first cover and the second cover, and the gap is formed by sealing the first cover and the second cover. The air layer shields heat from the fixing device to the equipment around the fixing device, and is forcibly disposed by the blowing means around the second cover and the second cover. Air from the outside of the image forming apparatus is sucked into the space between the devices through the air passage by the partition member from the air inlet, and the air in the space is exhausted from the air outlet to the outside through the air passage. Therefore, it is possible to effectively reduce the temperature rise of the surrounding units due to the temperature rise of the fixing device, and to suppress the power consumption required by the fixing device.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a second embodiment of the present invention.
FIG. 3 is a cross-sectional view illustrating a schematic configuration of a conventional image forming apparatus.
[Explanation of symbols]
2,3 Peripheral unit ( unit )
DESCRIPTION OF SYMBOLS 10 Fixing device 14 Second cover 15 First cover 16 Air layer 17, 18 Partition rib (partition member)
19 Exhaust port 20 Intake port 21 Blowing means P Recording material

Claims (2)

And an image forming process unit for forming an unfixed image onto the recording material, anda fixing device for fixing on the recording material by heating the unfixed image, at least a portion of the image forming process unit is the fixing device in the image forming apparatus surrounding units der Ru which is arranged around the,
Some have covering of the fixing device, and the first cover formed lengthwise end of the fixing device, covers the first cover, a gap formed lengthwise end between the first cover A second cover in which a hermetically sealed air layer is formed in the gap, and an air inlet formed between the second cover and the surrounding unit for sucking air outside the apparatus body and the outside of the apparatus body An air passage provided with an exhaust port for exhausting air to the air, and a partition member provided in the second cover and confining the air in the air passage between the second cover and the surrounding unit. An image forming apparatus. The image forming apparatus according to claim 1 , further comprising a blowing unit that blows air from the intake port to the exhaust port.

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