JPH11190967A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a image forming device which restricts rise in the temperature of a box allowing air to be flowed around the box needed to be cooled, which makes in possible to obtain a satisfactory image and operation, and which can be miniaturized. SOLUTION: The image forming device is provided with a through ventilation passage K3 connected to a hole 8a (inlet port) in an upper cover 8 (outer covering member) and piercing through the optical box 2 (box), and ventilation passage K1 and K2 connected to the through ventilation passage K3 and provided along the optical box 2. The device is also provided with a cooling means equipped with a fan 5 (blowing means) for discharging air in the ventilation passage K1 and K2 to the outside of the device.

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 forming an image on a sheet material, and more particularly to a technique for cooling an internal unit of the image forming apparatus.

[0002]

2. Description of the Related Art FIG. 6 shows a laser printer equipped with a process cartridge as a specific example of a conventional image forming apparatus.

FIG. 6 is an explanatory view of a cross-sectional structure of a laser printer.
1, an image is formed by an electrophotographic method, and the image is recorded on a recording material.

In the process cartridge 101, a photosensitive drum 102 serving as an image carrier is rotatably provided in a frame, and charging means for uniformly charging the surface of the photosensitive drum 102 around the photosensitive drum 102, Charged photosensitive drum 10
Developing means for developing a latent image formed by irradiating a light image corresponding to the image information with a developer (hereinafter, referred to as toner) to visualize the toner image as a toner image, and recording the toner image Cleaning means for removing toner remaining on the surface of the photosensitive drum 102 after transfer to the material P is provided;
These are integrated into a cartridge by a frame.

Incidentally, the laser printer has a mounting means for mounting the process cartridge 101 in the apparatus main body.

On the other hand, an optical system 103 for irradiating the photosensitive drum 102 with an optical image corresponding to image information is provided at an upper portion in the apparatus main body.

The recording material P stored in the paper feed cassette 104 is fed by a paper feed roller 105 and a separation claw 10 which are operated by a print signal from a host computer (not shown).
6, the sheets are separated and fed one by one.

The recording material P is conveyed after being turned upside down through a paper feeding reversing section including a conveying roller 107, a first roller 108, a second roller 109, and a third roller 110 (FIG. 6). Left). Then, the recording material P is guided by a transfer guide 111 and is conveyed to a pressure nip portion between the photosensitive drum 102 and the transfer roller 112.

On the other hand, image information from a host computer (not shown) is irradiated as an optical image from an optical system 103 onto a photosensitive drum 102 in a process cartridge 101 to form a latent image on the photosensitive drum 102 in accordance with the image information. The latent image is developed by toner and visualized.

The transfer material P is conveyed at a timing synchronized with image information developed as a toner image, and a voltage having a polarity opposite to that of the toner image formed on the photosensitive drum 102 is applied to the transfer roller 112 so as to be pressed. In the nip portion, the toner image on the photosensitive drum 102 is transferred to the recording material P.

Immediately after passing through the transfer section, the recording material P to which the toner image has been transferred passes immediately above a static elimination needle (not shown) and a static elimination needle holder 113 which guides the static elimination needle. The toner image is fixed by being conveyed to a fixing unit through a conveying path 115 provided in the fixing unit and passing through a fixing nip portion between a fixing film 116 of the fixing unit and a pressure roller 117.

The recording material P that has passed through the fixing section is again turned upside down through the rear portion of the apparatus main body behind the fixing section, and is discharged by a discharge roller 118 onto a discharge tray 119 provided at the top of the apparatus main body. You.

[0013]

The above-described conventional image forming apparatus (laser printer) suppresses heat generation by creating a flow of air around an optical box 120 accommodating an optical system 3 serving as a heat generating portion. When other units are in contact with the front, rear, left and right of the optical box 120, the outside air taken in from the upper surface or the lower surface of the main body can flow only on one of the upper and lower surfaces of the optical box 120 or indirectly. The effect may not be obtained. Therefore, the temperature inside the device may increase.

Further, in the configuration of the image forming apparatus having the conveyance path 115 for the recording material P above and below the optical box 120, if air is directly blown to the optical box 120 for cooling, the recording material P in the conveyance path 115 There is a problem that transportation becomes unstable.

In addition, the provision of a vent or a ventilation path beside the optical box 120 has a problem that the width of the optical box 120 or the main body becomes large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object the purpose of suppressing the temperature rise of a box by flowing air around the box that needs to be cooled, thereby achieving good image and operation. It is another object of the present invention to provide an image forming apparatus which can be obtained and can be reduced in size.

[0017]

In order to achieve the above object, according to the present invention, there is provided a transport path and transport means for transporting a sheet material, and a sheet disposed and transported in the middle of the transport path. An image forming unit for forming an image on a material, and a box including at least one of the units constituting the image forming unit therein and covering the unit so as to isolate the unit from the outside are arranged inside an exterior member of the apparatus. And, by the air sucked from outside the device through the exterior member,
In an image forming apparatus provided with a cooling unit that cools the inside of the apparatus and exhausts the air, the cooling unit is connected to an intake port provided in the exterior member, and penetrates through the box to ventilate. A ventilation path connected to the passage, the through-ventilation path, and provided through the ventilation path provided along the box; and an exhaust port provided in the exterior member, for discharging air in the ventilation path to the outside of the device. And the following.

Further, the ventilation path of the cooling means includes a first ventilation path between the inner surface of the exterior member and the box formed by disposing the box away from the inner surface of the exterior member; And a second ventilation path provided on the side opposite to the first ventilation path.

It is also preferable that the box is provided with an exposure scanning means for exposing a photosensitive member with a light image corresponding to image information formed therein.

It is also preferable that the transport path is arranged above or below the box.

Further, inside the box, there are provided a laser beam irradiating means which blinks in accordance with image information, and a deflecting means for deflecting the laser light, and the through-ventilation path is provided near the deflecting means of the box. And it is also preferred that it is located on the side opposite to the blowing means.

Therefore, it is possible to efficiently cool a box that requires cooling, and to stably convey the sheet material by suppressing the flow of air in the conveyance path, thereby reducing the size of the apparatus. It is also possible.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a perspective view of the periphery of an optical box 2 of a laser beam printer as an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of a laser beam printer as an image forming apparatus according to the embodiment of the present invention.

1 and 2, reference numeral 1 denotes a main body frame,
Reference numeral 2 denotes an optical box (hereinafter, referred to as an optical box 2) having a scanner unit (exposure scanning means) as a box for irradiating the photosensitive drum with an optical image corresponding to image information. It is a ventilation duct that constitutes a ventilation path K2 as a second ventilation path attached.

Reference numeral 4 denotes a recording material P as a transferred sheet material
Is a fixing device for applying temperature-controlled heat to the apparatus, 5 is a fan as a blower for flowing air in the main body to the outside, and 6 is a drive side plate for fixing a drive gear and the like provided in the transfer means.

Reference numeral 7 denotes a cassette for accommodating a recording material before transfer, 8 denotes an upper cover as an exterior member also serving as a paper discharge tray, and 9 denotes laser light irradiation means in the optical box 2 according to image information. This is a rotation axis for rotating a deflector (polygon mirror) as a deflecting means for deflecting the laser beam that blinks.

One side of the optical box 2 (the side opposite to the fan 5)
Then, a hole 2a that penetrates up and down to form a through-air passage K3 is formed. Further, a hole 8a as an air inlet for taking air into the upper cover 8 above the hole 2a opened in the optical box 2.
(Louver shape).

The arrangement of the optical box 2 depends on the inner surface 8 b of the upper cover 8.
, And a ventilation path K1 as a first ventilation path is also formed between the inner surface 8b and the upper surface of the optical box 2.

Accordingly, the cooling means for cooling the optical box 2 includes the hole 8a of the upper cover 8, the hole 2a provided in the optical box 2, the ventilation path K1 and the duct 3, the fan 5, and the exhaust part 5a. Will be prepared.

As a result, when the fan 5 is turned, the air entering through the hole 8 a of the upper cover 8 passes through the ventilation path K 1 and the duct 3 while contacting both the upper and lower surfaces of the optical box 2, and is exhausted by the fan 5. Since the air is exhausted from the portion 5a to the outside of the main body, when the air around the optical box 2 is operated,
It always flows in the direction of the fan 5 and the temperature rise of the optical box 2 can be prevented.

On the other hand, from the holes penetrating the optical box 2 above and below,
Motor rotating shaft 9 located on the lower surface of optical box 2 as a heat source
(Or bearing) through the duct 3 to the fan 5
Is provided.

As a result, the air entering from outside the main body flows through the duct 3 to the fan 5, so that a high temperature near the heat generating portion (the motor rotating shaft 9 and the laser beam irradiating means and the deflector). It is possible to prevent the air from staying.

Further, by adjusting the width of the duct 3 near the heat generating portion, it is possible to change the speed of the air flow, so that efficient cooling can be performed.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a longitudinal sectional view of a laser beam printer which is an image forming apparatus according to a second embodiment of the present invention.

Since the basic structure of the main body in this embodiment is the same as that of the first embodiment, the same reference numerals in FIG. 3 denote the same parts as those shown in FIGS. In the following, description thereof will be omitted.

Reference numeral 10 denotes a cartridge constituting a part of an image forming means for transferring to the recording material P, 11 denotes an electric board on which electric components are mounted, and 12 denotes a paper discharge unit on which the fixed recording material P is stacked. is there.

In this embodiment, a transfer path H for the transferred recording material P is provided below the optical box 2, and a paper discharge section 12 for the fixed recording material P is provided above the optical box 2. ing.

The flow of air from the upper cover 8 to the fan 5 is performed only on the upper side of the optical box 2, the duct 3 below the optical box 2, and the electrical unit 11. There is no recording material P on the upper part of the optical box 2 (above the upper cover 8 not including the area of the ventilation path K1) or the lower part.
Recording material P due to the flow of air
There is no adverse effect such as turning over.

A similar duct shape is used for the cartridge 10.
Of course, it may be formed by a rib or the like on the upper surface.

At this time, as shown in FIG. 4, it is possible to simultaneously ensure a sufficient flow of air on the upper surface of the cartridge 10.

Here, 10a is the cartridge body, 10a
b is a scanner, 10c is a rib on the upper surface of the cartridge 10 forming a duct (second ventilation path), and 10d is a scanner motor bearing.

(Embodiment 3) A third embodiment of the present invention will be described with reference to FIG. FIG. 5 shows a third embodiment of the present invention.
FIG. 2 is a perspective view of the vicinity of an optical box 2 of the laser beam printer as the image forming apparatus according to the embodiment.

Since the basic structure of the main body in this embodiment is the same as that of the first embodiment, the same reference numerals in FIG. 5 denote the same elements as those shown in FIGS. In the following, a description thereof will be omitted.

In FIG. 5, 13 is a folding mirror for sending image information to a drum, 14 is an optical lens for projecting image information to a polygon mirror which is a deflector, and 15 is a deflector for laser light (hereinafter referred to as an optical motor). .

Since the optical box 2 contains the folding mirror 13, the optical lens 14, the optical motor 15, and the like, the optical box has a fan-like shape, and wasteful areas are formed on both sides of the optical motor 15. . A hole 2 a is provided on the opposite side of the fan 5 in the two areas. As a result, the width (W) of the optical box 2 becomes substantially the same as the length of the folding mirror 13, and can be minimized, so that the size of the apparatus can be reduced.

[0047]

As described in the embodiment of the present invention, a box requiring cooling can be efficiently cooled, and a stable sheet can be obtained by suppressing the flow of air in a conveying path. The material is conveyed, and a good image can be formed.

Further, since the through-air passage is provided in the empty space of the box, the width of the apparatus main body can be minimized and the size can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view around an optical box of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a cross-sectional configuration of an optical box of the image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a cross-sectional configuration of an image forming apparatus according to a second embodiment of the present invention.

FIG. 4 is a diagram illustrating a cross-sectional configuration of an image forming apparatus according to a second embodiment of the present invention.

FIG. 5 is a perspective view around an optical box of an image forming apparatus according to a third embodiment of the present invention.

FIG. 6 is an explanatory view of a longitudinal configuration of an image forming apparatus according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body frame 2 Optical box (box) 2a hole 3 Duct 4 Fixing device 5 Fan (blowing means) 6 Drive side plate 7 Cassette 8 Upper cover (exterior member) 8a Hole (intake port) 8b Inner surface 9 Rotating shaft 10 Cartridge 11 Electrical equipment Unit 12 paper discharge unit 13 folding mirror 14 optical lens 15 optical motor K1 ventilation path (first ventilation path) K2 ventilation path (second ventilation path) K3 through ventilation path P recording material (sheet material)

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Taku Goto 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (5)

[Claims] 1. A transport path and transport means for transporting a sheet material, an image forming means disposed in the middle of the transport path and forming an image on the transported sheet material, and the image forming means. A box that includes at least one of the units therein and covers the unit so as to isolate the unit from the outside; and disposing a box inside the exterior member of the device, and by air that is sucked in from the outside of the device via the exterior member, In an image forming apparatus including a cooling unit that cools the inside of the apparatus and performs exhaust, the cooling unit is connected to an intake port provided in the exterior member,
A through-ventilation path through which the box is ventilated, a ventilating path connected to the through-venting path and provided along the box, and an exhaust port provided in the exterior member, An image forming apparatus, comprising: a blower that exhausts air to the outside of the apparatus. 2. A ventilation path of the cooling means, wherein: a first ventilation path between the inner surface of the exterior member and the box formed by disposing the box away from the inner surface of the exterior member; The image forming apparatus according to claim 1, further comprising: a second ventilation path provided on a side opposite to the first ventilation path. 3. The image forming apparatus according to claim 1, wherein the box includes an exposure scanning unit that exposes a photoconductor with a light image corresponding to image information to be formed in the box. 4. The image forming apparatus according to claim 1, wherein the transport path is arranged above or below the box. 5. Inside the box, there are provided a laser beam irradiating unit which blinks according to image information, and a deflecting unit which deflects the laser beam, wherein the through-ventilation path is near the deflecting unit of the box. And
The image forming apparatus according to any one of claims 1 to 4, wherein the image forming apparatus is located on a side opposite to the blowing unit.