JPH1165403A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the cooling efficiency and the exhausting efficiency of a dust without increasing the number of parts in an image forming device constituted so that the duct is cooled by passing outdoor air through it and the fixing heat of a fixing unit is cut off. SOLUTION: The duct 34 extended in the back-and-forth direction of a machine main body (device main body) 10 is arranged between the fixing unit and the cleaning unit 15 of an image forming part 16 in the main body 10. The armor cover 42 of the main body 10 is provided with a cylindrical part 42a facing inside by integral molding so as to form an air intake 42b. Then, the intake 42b is made to communicate with the inside of the duct 34. Namely, the front end of the duct 34 is made to abut on the tip of the part 42a through a seal member 43 and coupled to the cover 42. Thus, when a fan 35 is actuated, the air is taken in from the intake 42b and passed through the inside of the duct 34 so as to remove heat around the duct 34. As the result, the fixing heat of the fixing unit is cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can be applied to an image forming apparatus such as a copying machine, a printer, a facsimile, and a multifunction peripheral thereof. More specifically, the present invention can be applied particularly to an image forming apparatus of a type in which a fixing unit applies heat together with pressure, for example, to thermally fix a transferred image on a recording medium. More specifically, the present invention relates to an image forming apparatus in which a duct extending in the front-rear direction of the apparatus main body is provided adjacent to such a fixing unit, the duct is cooled by passing outside air, and the fixing heat of the fixing unit is cut off.

[0002]

2. Description of the Related Art In recent years, for example, in a copying machine, the space between each unit in the main body of the copying machine has become narrower and the space between the units has become narrower. For this reason, when the fixing unit receives the fixing heat, for example, the temperature of the developer in the developing unit may rise and the toner may be scattered, or the toner in the cleaning unit may be solidified and the toner collecting mechanism may be locked. .

Therefore, in a conventional copying machine, a heat shield plate is provided between the fixing unit and the image forming unit, thereby blocking the fixing heat of the fixing unit and affecting the cleaning unit and the developing unit of the image forming unit. Had no effect. However, the heat shielding plate has a small heat capacity and does not have a sufficient heat shielding effect. For this reason, there has been a case where a duct is provided around the fixing unit. For example, as shown in FIG.
A duct 3 having a higher heat shielding property than a heat shield plate is provided between the fixing unit 1 and the image forming unit 2, and the fixing heat of the fixing unit 1 is changed by the cleaning unit 4 and the developing unit (not shown) of the image forming unit 2.
There was something that was not affected.

The duct 3 extends in the front-rear direction of the apparatus main body A, and has a front end supported by a front plate 5a and a rear end supported by a rear plate 5b. The inner end of the extension duct 7 is connected to the front end via a seal member 6. The outer end side opening of the extension duct 7 faces the outside air intake port a of the exterior cover 8a on the front side of the apparatus main body A. On the other hand, an exhaust fan 9 is provided on the rear end side of the duct 3. The rear side of the exhaust fan 9 was opposed to the exhaust port b of the exterior cover 8b on the rear side of the apparatus main body A.

Then, for example, when the apparatus main body A is driven,
The exhaust fan 9 is actuated to take in outside air from the outside air intake port a, exhaust through the duct 3 and exhaust from the exhaust port b. At this time, heat around the duct 3 is cooled and the fixing heat of the fixing unit 1 is cut off. The fixing heat does not affect the cleaning unit 4 and the developing unit (not shown) of the image forming unit 2.

[0006]

However, in this type of conventional copying machine, since there is a gap s between the extension duct 7 and the outer cover 8a, when the exhaust fan 9 is operated,
The air in the apparatus main body A is also sucked into the duct 3. Then, since the air in the apparatus main body A is warm, there is a problem that the cooling efficiency of the duct 3 is reduced.

Further, since air in the apparatus main body A contains ozone and dust, the air is exhausted through an ozone filter or a dustproof filter, and there is a problem that the exhaust efficiency is reduced. For this reason, when the gap s is closed by the seal member, the number of parts increases correspondingly, and there is a problem that the cost increases.

Accordingly, an object of the present invention is to increase the cooling efficiency of a duct without increasing the number of parts in an image forming apparatus which cools a fixing unit by passing outside air and cools the fixing unit as described above. In addition, it is to improve the exhaust efficiency.

[0009]

Therefore, according to the present invention, a duct extending in a front-rear direction of an apparatus main body such as an apparatus main body 10 as described in an embodiment shown in FIGS. In an image forming apparatus such as a copying machine, a printer, a facsimile, or a multifunction machine thereof, which cools the fixing heat of the fixing unit 18 by passing outside air through the duct 34, the fixing unit 18 is integrated with the outer cover 42 of the apparatus main body. An outside air inlet 42b is formed by forming an inward cylindrical portion 42a by molding, and the outside air inlet 42b and the duct 3 are formed.
4, and one end of the duct 34 is connected to the outer cover 42 so as to communicate with the inside of the casing.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, for example, one end of the duct is connected to one end as described in the embodiment shown in FIG.
It is characterized in that it is connected to the outer cover 42 by abutting on the tip of the cylindrical portion 42a via a sealing member 43.

The invention according to claim 3 is the same as in claim 1
2, one end of the duct 34 is inserted into the cylindrical portion 42a and the outer cover 42 is inserted as described in an embodiment shown in FIG.
Characterized by being connected to

When the apparatus body is driven, for example, outside air is taken in only from the outside air inlet 42b of the outer cover 42, and discharged outside the apparatus body through the duct 34. At this time, the outside air passing through the duct 34 takes heat around the duct 34 to cool it.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 4 shows a schematic configuration of an internal mechanism of a copying machine according to the present invention. Reference numeral 10 in the figure
Denotes a machine body (apparatus body).

A drum-shaped image carrier 1 is provided in a main body 10 of the machine.
1, a charging unit 12, a developing unit 13, a transfer / transport unit 14, a cleaning unit 15, and the like are arranged therearound to form an image forming unit 16. And
A writing unit 17 is provided above the image forming unit 16.

A fixing unit 18 is provided on the left side of the image forming section 16 in the drawing. The fixing unit 18 includes a fixing roller 19 having a built-in heater and a pressure roller 20 pressed against the fixing roller 19.

A reading optical system 21 is provided on the image forming section 16 and the fixing unit 18. On the other hand, below the image forming unit 16 and the fixing unit 18, a double-sided unit 22 and a paper feed cassette 23 are provided in two upper and lower stages. A paper feed path 24 is formed from the duplex unit 22 and the paper feed cassette 23 toward the lower side of the image carrier 11,
Further, a reversing path 26 is formed branching from the middle of the sheet discharging path 25 extending from the exit of the fixing unit 18 toward the duplex unit 21.

A contact glass 27 is mounted on the upper surface of the machine body 10. The contact glass 2
An automatic document supply unit 28 is mounted on the main body 10 so as to be openable and closable so as to cover the cover 7.

A manual tray 2 for guiding manual paper (recording medium) to a paper feed path 24 is provided on the right side of the machine body 10.
9 is provided to be freely opened and closed. Although illustration is omitted on the left side,
A paper discharge tray for receiving the paper discharged through the paper discharge path 25 is detachably attached.

When making a copy using this copying machine, a document is set on the automatic document supply unit 28 or the document is directly opened on the contact glass 27 by opening the automatic document supply unit 28 as is well known. set.
Then, a start switch (not shown) is pressed to drive the automatic document supply unit 28 to drive the original conveyed onto the contact glass 27 or the contact glass 27 in advance.
The original set above is read by the reading optical system 21.

At the same time, the paper feed roller 30 is rotated, and the paper (recording medium) in the paper feed cassette 23 is sent out to the paper feed path 24 and is transported by a plurality of transport rollers 31. It is fed below the image carrier 11 in synchronization with the rotation of. Or, the paper feed roller 33
Is rotated, the manual paper set on the opened manual feed tray 29 is inserted into the paper feed path 24, and the registration rollers 3
In 2, the sheet is fed below the image carrier 11 in synchronization with the rotation of the image carrier 11.

On the other hand, the image carrier 11 is rotated clockwise in the figure, first the surface is uniformly charged by the charging unit 12, and then a laser beam is irradiated according to the read content read by the above-mentioned reading optical system 21. Then, writing is performed by the writing unit 17, an electrostatic latent image is formed on the surface of the image carrier 11, and then the toner is adhered by the developing unit 13 to visualize the electrostatic latent image.

Then, the visible image is transferred by the transfer / transport unit 14 to the sheet fed below the image carrier 11 as described above. The residual toner on the image carrier 11 after the image transfer is removed by the cleaning unit 15 and cleaned to prepare for the next similar image formation.

On the other hand, the sheet after the image transfer is conveyed by the transfer / conveyance unit 14 and is fixed by the fixing roller 1 of the fixing unit 18.
9 and the pressure roller 20, and heat and pressure are applied between them to fix the transferred image. Thereafter, the paper is discharged onto a paper discharge tray (not shown) through the paper discharge path 25.

When recording is performed on the back side of a sheet using this copying machine, after recording on one side, the recording sheet is put into the double-sided unit 22 through the reversing path 26, where it is reversed and again moved below the image carrier 11. The image is sent, the image separately formed on the image carrier 11 is similarly transferred to the back surface, and then discharged onto the paper discharge tray.

FIG. 3 schematically shows an enlarged view of a main part of an internal mechanism of the above-described copying machine. As can be seen from the drawing, in this copying machine, a duct 34 extending in the front-rear direction of the machine body 10 is provided between the fixing unit 18 and the cleaning unit 15 of the image forming unit 16. The duct 34 is made of resin, metal, or a combination thereof, and has an appropriate shape in consideration of heat shielding properties, the shape of the space between the fixing unit 18 and the image forming unit 16, and the like. A fan 35 is provided behind the duct 34.

FIG. 1 is a sectional view showing the vicinity of the duct portion. As can be seen from this figure, the duct 34 is provided so as to bridge between the front side plate 40 and the rear side plate 41 of the machine body 10, and also functions as a stay for firmly connecting them.

Reference numeral 42 in FIG. 1 denotes a resin outer cover on the front side of the machine body 10. The exterior cover 42 is integrally formed with an inwardly directed cylindrical portion 42a to form an outside air intake 42b. The outside air inlet 42 b communicates with the inside of the duct 34, and the front end of the duct 34 abuts on the tip of the cylindrical portion 42 a via a seal member 43, and is connected to the exterior cover 42.

Reference numeral 44 in FIG. 1 denotes a resin outer cover on the back side of the machine body 10. The exterior cover 44 is provided with an exhaust port 44a. The above-described fan 35 is arranged inside the exhaust port 44a.

Then, for example, when the machine body 10 is driven,
The fan 35 is operated, and the outside air intake 4
The outside air is taken in from 2b and discharged from the exhaust port 44a through the duct 34. At this time, the heat around the duct 34 is taken away by the air passing through the duct 34 to cool it, and the fixing heat of the fixing unit 18 is cut off, and the fixing heat affects the cleaning unit 15 and the developing unit 13 of the image forming unit 16. Not to affect.

In the example shown in FIG. 1, the seal member 43 is provided between the front end of the duct 34 and the tip of the cylindrical portion 42a. However, as shown in FIG. 2, the front end of the duct 34 is inserted into the cylindrical portion 42a. Alternatively, it may be connected to the exterior cover 42. In this way, the duct 34 and the cylindrical portion 42a overlap, and it is possible to prevent the air in the machine body 10 from entering the duct 34 without using the seal member 43.

[0031]

Therefore, according to the first to third aspects of the present invention, the gap between the duct and the outer cover is eliminated, only the outside air is introduced into the duct, and the warm air inside the apparatus body does not enter. With such a configuration, the cooling efficiency of the duct can be increased and the heat shielding effect can be enhanced.

Further, since air in the apparatus main body is prevented from entering the duct, ozone and dust generated around the image carrier in the apparatus main body are prevented from being discharged outside the apparatus main body through the duct. There is no need to attach an ozone filter or a dustproof filter to the exhaust port, so that the number of parts can be reduced and exhaust efficiency can be improved.

According to the third aspect of the present invention, in addition to the above effects, one end of the duct is inserted into the cylindrical portion and connected to the exterior cover, so that a seal member provided between the duct and the exterior cover is provided. It is not necessary, and the number of parts can be reduced to reduce the cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the vicinity of a duct portion of a copying machine according to the present invention.

FIG. 2 is a cross-sectional view of a vicinity of a duct portion of another example.

FIG. 3 is an enlarged perspective view schematically showing a main part of an internal mechanism of the copying machine.

FIG. 4 is a schematic configuration diagram of an internal mechanism of the copying machine.

FIG. 5 is a cross-sectional view of the vicinity of a duct portion of a conventional copier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Machine main body (apparatus main body) 18 Fixing unit 34 Duct 42 Exterior cover 42a Cylindrical part 42b Outside air intake 43 Seal member

Claims (3)

[Claims] 1. An image forming apparatus comprising: a duct extending in a front-rear direction of an apparatus main body; cooling the fixing heat of a fixing unit by passing outside air through the duct; An image forming apparatus comprising: a tubular portion provided with an outside air intake; a communication between the outside air intake and the duct; and one end of the duct connected to the exterior cover. 2. The image forming apparatus according to claim 1, wherein one end of the duct is connected to the outer cover by abutting a distal end of the cylindrical portion via a seal member. 3. The image forming apparatus according to claim 1, wherein one end of the duct is inserted into the cylindrical portion and connected to the exterior cover.