JP2000259065A - Image forming device - Google Patents

Abstract

(57) Abstract: An object of the present invention is to enable efficient cooling or exhaustion in a wide range in an image forming apparatus that transmits drive by a drive belt. In order to solve the above problem, an image forming apparatus according to the present invention is an image forming apparatus having a drive belt for transmitting a drive, wherein the case substantially covers an entire drive system formed by the drive belt. The member 43 and the case member
And a blower fan 44 for cooling the inside of the drive belt 36, wherein the blower fan 44 is configured to cool the vicinity of the track of the drive belt 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for transmitting a drive by using a drive belt, and more particularly, to solving a problem caused by a temperature rise in the apparatus.

[0002]

2. Description of the Related Art An electrophotographic image forming apparatus will be described as an example of an image forming apparatus having a drive belt for transmitting a drive. Generally, conventionally, in an electrophotographic image forming apparatus, a sheet conveying unit that supplies and conveys a sheet from a sheet stacking unit, a photosensitive drum that holds an electrostatic latent image, a re-feeding unit for performing double-sided recording, and the like, It has a plurality of means that require driving. Of these, those which mainly drive at a constant speed are usually provided with a common drive source by a drive belt to simplify the configuration.

FIG. 11 is a schematic rear view of a conventional image forming apparatus.
FIG. 12 shows a schematic side view of the image forming apparatus. The image forming apparatus shown in the figure has a drive transmission mechanism using a drive belt 102 between a main body rear frame 100 and a rear cover 101. That is, the driving pulley 1 is
A drive belt 102 is stretched between the drive pulley 104 and the drive input pulleys 105, 106, and 107 of each section. The drive belt 102 includes tensioners 108 and 10
9 keeps the right tension. Motor 103
When the image forming operation is started, the driving belt 102 is driven to rotate in the direction of the arrow in the figure, and the driving force is transmitted to each unit.

[0004]

In such an image forming apparatus, the number of components used in recent years has been increasing along with its high image quality and high speed, and the heat source that causes the temperature inside the machine to be increased is also the electric component. With the increase, it is becoming scattered in each part. Especially the rear frame 100 and the rear cover 101
Many components such as each drive mechanism, an electric board, and a power supply are mounted at high density in the space between them, and it is difficult to construct an overall cooling airflow. For this reason, even if a cooling mechanism is provided, it often has only a local cooling effect, and it is difficult to efficiently cool the entire apparatus.

When an exhaust mechanism is provided as a cooling mechanism for discharging air inside the apparatus to the outside of the apparatus, toner dust and an ozone layer generated in the apparatus are not discharged to the outside of the apparatus. It is necessary to provide a filter, and providing many exhaust mechanisms is not desirable in terms of cost and maintenance load.

Accordingly, the present invention provides an image forming apparatus in which drive is transmitted by a drive belt, which provides efficient cooling over a wide range.
Alternatively, the purpose is to enable exhaust.

[0007]

In order to solve the above-mentioned problems, an image forming apparatus according to the present invention is directed to an image forming apparatus having a drive belt for transmitting a drive, wherein an entire drive system formed by the drive belt is used. It is characterized by having a case member that covers substantially, and cooling means for cooling the inside of the case member, wherein the air blowing means is configured to cool the vicinity of the track of the drive belt.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment of an image forming apparatus according to the present invention will be described with reference to the drawings. 1 is an overall configuration diagram of the image forming apparatus according to the present embodiment, FIG. 2 is a schematic rear view of the image forming apparatus, FIG. 3 is a schematic side view of the image forming apparatus, FIG. FIG. 5 is a side view illustrating the vicinity of the cooling means, and FIG. 6 is a rear view illustrating the cooling airflow.

The image forming apparatus shown in FIG. 1 transmits a signal to a plurality of means by using a drive belt as described later.
An electrophotographic color image forming apparatus that forms a full-color image by forming an electrostatic latent image on an image carrier made of a photoreceptor, developing the latent image and transferring the latent image to a sheet.

An image reading section 2 is provided on an upper portion of the apparatus main body 1, and an original S placed on an original table glass 10 is exposed by an exposure lamp.
Exposure scanning by 11 causes the reflected light image from the document to be condensed on the full color sensor 14 by mirrors 12a, 12b, 12c and lens 13 to obtain a color separation image signal.

The color-separated image signal is processed by a video processing unit via an amplifying circuit (not shown) and sent to an image forming unit. In the image forming unit, when a signal for starting image formation is input, first, a photosensitive drum serving as an image carrier
15 is driven to rotate in the direction of arrow A by driving means (not shown). Around the photosensitive drum 15, a pre-exposure lamp 16, a corona charger 17, a laser exposure optical system 18 as an exposure means, a potential sensor 19, and four developing units 20y, 20c, 20m, 20 of different colors.
Bk, on-drum light amount detecting means 21, transfer device 3, and cleaning device 22 are arranged.

After the rotation of the photosensitive drum 15 starts, the transfer drum 23 of the transfer device 3 is pressed against the photosensitive drum 15 by the transfer drum pressing cam 34, and is driven by the photosensitive drum 15 to rotate at a constant speed. To start. When the rotation of the photosensitive drum 15 is stabilized and preparation for sheet conveyance is completed, the photosensitive drum 15
Starts an image forming operation.

In the laser exposure optical system 18, an image signal from an image reading section is converted into an optical signal by a laser output section (not shown), and the converted laser light is reflected by a rotary polygon mirror 18a, and a lens 18b and a mirror are provided. 18c through photosensitive drum
Projected on 15 cylindrical surfaces. During image formation, the photosensitive drum 15
Is rotated in the direction of arrow A, and the photosensitive drum 15 after the charge is eliminated by the pre-exposure lamp 16 is uniformly charged by the corona charger 17 to irradiate a light image for each separation color to form an electrostatic latent image. I do.

Next, by operating a predetermined developing device, the latent image on the photosensitive drum 15 is developed, and a toner image is formed on the photosensitive drum 15 using a resin as a base. The developer is an eccentric cam 25y,
With the operations of 25c, 25m, and 25Bk, the photosensitive drum 15 is selectively approached in accordance with each separation color. The toner image formed on the photosensitive drum 15 in this manner is
The image is transferred from the sheet cassette 4 to a sheet supplied to a position facing the photosensitive drum 15 via the transfer system and the transfer drum 23.

The transfer drum 23 has therein a transfer charger 26, an attraction charger 27 for electrostatically attracting a sheet, and an inner static elimination charger 28, and as a whole, the photosensitive drum as described above.
15 is pressed against. The transfer drum 23 to which the sheet is electrostatically attracted transfers the toner image on the photosensitive drum 15 onto the sheet by the transfer charger 26 according to the rotation.

In this manner, a desired number of color images are transferred to the sheet attracted and conveyed to the transfer drum 23, and a full-color image is formed when the transfer of the four color toner images is completed.
When the transfer is completed, the sheet is separated from the separation claw 29,
After being separated from the transfer drum 23 by the action of the toner 30 and the toner is fixed via the heat roller fixing device 31, the toner is discharged to the discharge tray 32. When image formation is continuously performed on a plurality of sheets, the next sheet is subsequently conveyed to the transfer drum 23, and the image forming operation on the photosensitive drum 15 and the transfer operation on the sheet are repeated.

After the final sheet is separated, the transfer drum 23 is pressed by the photosensitive drum 15 as it is and is driven to rotate.
The transfer drum cleaner 33 cleans the surface.
The cleaning operation is performed for at least one rotation of the transfer drum 23. When the cleaning is completed, the transfer drum pressing cam 34 rotates, and the transfer drum 23 is separated from the photosensitive drum 15. The rotation of the photosensitive drum 15 is stopped after the transfer drum 23 is separated.

As shown in FIGS. 2 and 3, a drive transmission mechanism by a drive belt 36 is provided between the rear frame 1a and the rear cover 1b on the rear surface of the apparatus. That is, a drive pulley 37 is attached to an output shaft of a motor 35 as a drive source, and a drive belt 36 is stretched between the drive pulley 37 and the drive input pulleys 38, 39, and 40 of each unit. . The drive belt 36 is maintained at an appropriate tension by the tensioners 41 and 42.

Here, the drive input pulley 38 is a waste toner conveying mechanism of the cleaning device 22, and the drive input pulley 39 is a developing device.
The drive input pulley 40 transmits the drive to the development sleep rotation mechanism 20 and the suction input roller rotation mechanism facing the lower right of the transfer drum 23. As described above, when the image forming operation is started, the motor 35 rotates, and the driving belt
36 is driven in the direction of arrow B in the figure, and the driving force is transmitted to each part.

The entire drive system by the drive belt 36 is substantially covered by a case member 43 formed of a metal plate. As shown in FIGS. 4 and 5, the case member 43 is provided with an intake port 43a at a position corresponding to the trajectory of the drive belt 36, and a blower fan 44 serving as a cooling means is provided corresponding to the intake port 43a. Duct 45 is supported. Duct 45
Of the rear cover 1b is provided with a sealing member on the opening louver 1c.
It engages via 46 (see FIG. 5) and vents out of the device.

When the drive belt 36 is driven, the blower fan
Cooling air supplied from outside of the apparatus by 44 is fed into the inside of the case member 43 from the intake port 43a as indicated by a dashed arrow C in FIG. The cooling air clings to the drive belt 36 as shown by an arrow D in FIG.
It is transported to each part in 43 and used for cooling each part.

With this configuration, in the image forming apparatus according to the present invention, a wide range can be efficiently cooled with an extremely simple configuration, and a problem caused by a temperature rise in the apparatus can be prevented. Can be.

[Second Embodiment] Next, a second embodiment of the image forming apparatus according to the present invention will be described with reference to the drawings.
7 is a schematic rear view of the image forming apparatus according to the present embodiment, FIG. 8 is a schematic side view of the image forming apparatus, FIG. 9 is a side view illustrating the vicinity of the cooling unit, and FIG. 10 is a rear view illustrating the cooling airflow. is there.

In this embodiment, similarly to the first embodiment,
A drive transmission mechanism by a drive belt 36 is provided between the main body rear frame 1a and the rear cover 1b on the rear surface of the apparatus, and a drive input pulley 38 of each part is provided from a drive pulley 37 attached to the motor 35.
Drive is transmitted to the driving belts 39 and 40 by the driving belt 36.

The entire drive system by the drive belt 36 is substantially covered by a case member 47 formed of a metal plate. As shown in FIG. 9, a duct 48 is provided at a position corresponding to the track of the drive belt 36, which is a part of the case member 47, and the duct 48 is provided with an intake port 48a and an exhaust port 48b. . Each of the intake port 48a and the exhaust port 48b is engaged with a louver of the rear cover 1b via a seal member 46 so as to open to the outside of the apparatus (see FIG. 9), and a blower fan 44 is attached to the duct 48. To generate an air flow in the duct. The inside of the duct 48 is sealed from other spaces in the apparatus, so that air outside the apparatus is sucked and discharged outside the apparatus as it is.

When the drive belt 36 is driven, FIGS.
As shown in (1), the air heated from each part is conveyed to the position of the duct 48 in the form of being attached to the drive belt 36. The heated air radiates heat into the duct 48 via the case member 47, which is a metal plate, while passing through the position of the duct 48, is cooled, and is conveyed to the respective parts by the drive belt 36 as it is. On the other hand, the temperature of the airflow in the duct 48 rises due to heat radiation from the case member 47, but the airflow is quickly discharged out of the apparatus by the operation of the blower fan 44. Here, the reason why the case member 47 is formed of metal is to make the thermal conductivity good. This not only facilitates the transfer of heat from the inside of the device into the duct 48, but also can function as a heat sink.

Therefore, the air flow in the duct 48 is always kept in a cooled form, and the efficiency of heat radiation from the case member 47 can always be kept good. In addition, since the air exhausted from the duct 48 is shut off from the inside of the apparatus and only obtains heat, there is no possibility that toner dust, ozone, etc. are released to the outside, and the air can be exhausted without using a filter or the like. it can.

As described above, in the image forming apparatus according to the present embodiment, a wide range can be efficiently cooled with a simple configuration without using a filter or the like, and the problem caused by the temperature rise in the apparatus is obviated. Can be prevented.

In each of the above embodiments, the blower fan 44, which is a cooling means, is configured to suck airflow into the apparatus. However, the present embodiment is not limited to this. The same effect can be obtained even with an object that generates an airflow.

[0030]

As described above, in the image forming apparatus according to the present invention, the driving belt driven in the case member conveys the surrounding air while entraining the surrounding air. It is possible to efficiently cool a wide range, and it is possible to prevent a problem caused by a temperature rise in the apparatus.

Further, since the air flow in the vicinity of the drive belt is indirectly cooled via the case member, the cooled air flow can be circulated over a wide area in the apparatus, and the toner generated in the apparatus can be circulated. There is no possibility of discharging dust, ozone, and the like to the outside, and the configuration such as a filter can be omitted to achieve a simple configuration.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an image forming apparatus according to a first embodiment.

FIG. 2 is a schematic rear view of the image forming apparatus.

FIG. 3 is a schematic side view of the image forming apparatus.

FIG. 4 is a rear view illustrating the vicinity of a cooling unit.

FIG. 5 is a side view illustrating the vicinity of a cooling unit.

FIG. 6 is a rear view illustrating a cooling airflow.

FIG. 7 is a schematic rear view of the image forming apparatus according to the second embodiment.

FIG. 8 is a schematic side view of the image forming apparatus.

FIG. 9 is a side view illustrating the vicinity of a cooling unit.

FIG. 10 is a rear view illustrating a cooling airflow.

FIG. 11 is a schematic rear view of an image forming apparatus according to a conventional example.

FIG. 12 is a schematic side view of an image forming apparatus according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Device main body 1a ... Main body rear frame 1b ... Rear cover 1c ... Opening louver 2 ... Image reading part 3 ... Transfer device 4 ... Sheet cassette 10 ... Original platen glass 11 ... Exposure lamp 12a ... Mirror 13 ... Lens 14 ... Full color sensor 15 ... Photosensitive drum 16 ... Pre-exposure lamp 17 ... Corona charger 18 ... Laser exposure optical system 18a ... Rotating polygon mirror 18b ... Lens 18c ... Mirror 19 ... Potential sensor 20 ... Developing device 21 ... Drum on-drum light detecting means 22 ... Cleaning device 23 … Transfer drum 25… Eccentric cam 26… Transfer charger 27… Adsorption charger 28… Inside static eliminator 29… Separation claw 30… Separation pushing roller 31… Heat roller fuser 32… Discharge tray 33… Transfer drum cleaner 34… Transfer Drum pressure cam 35… Motor 36… Drive belt 37… Drive pulley 38… Drive input pulley 39… Drive input pulley 40… Drive input pulley 41… Tension Over 42 ... tensioner 43 ... case member 43a ... suction port 44 ... blower fan 45 ... duct 46 ... sealing member 47 ... case member 48 ... duct 48a ... suction port 48b ... outlet

Claims (7)

[Claims] 1. An image forming apparatus having a drive belt for transmitting drive, comprising: a case member that substantially covers an entire drive system formed by the drive belt; and a cooling unit that cools the inside of the case member. An image forming apparatus, wherein the blower cools the vicinity of the track of the drive belt. 2. The image forming apparatus according to claim 1, wherein the cooling unit is a blowing unit that generates an airflow, and is configured to suck or exhaust the airflow near a track of the drive belt. 3. The image forming apparatus according to claim 1, wherein the cooling unit cools the case member so as to indirectly cool an airflow near a track of the drive belt. 4. The image forming apparatus according to claim 3, wherein the case member has at least a portion related to the cooling unit formed of a material having high thermal conductivity. 5. The image forming apparatus according to claim 3, wherein the cooling unit is a duct provided at a position corresponding to a vicinity of a track of the drive belt of the case member. 6. The image forming apparatus according to claim 5, wherein both the intake port and the exhaust port of the duct are open to the outside of the apparatus, and the duct is sealed inside the apparatus. 7. The cooling device according to claim 5, wherein the cooling device includes a blowing device for generating an air flow in the duct.
The image forming apparatus as described in the above.