JPH02253270A - Image forming device - Google Patents

Abstract

PURPOSE:To simplify a carrying path of a recording paper for face down paper ejecting, to miniaturize the device main body, and to lighten the device by providing a transferring means in the side as well as on a mobile body side of a photosensitive body, and at the same time providing an ejecting part of the recording paper in the bottom part of the device. CONSTITUTION:In the immobile body 1 of the device main body which contains an image forming structure, the paper ejecting opening 3 which ejects the recording paper from a paper ejecting roller 2 and the mobile body 4 which is attached openable/closable by a hinge are attached to the bottom part on the side which becomes the front when mounted. Further, on both sides of the interior, side plates which support various units, and in a part further up, a cut sheet feeder 6 able to travel by guiding constructions 7 and 7 are provided. Further, separated by the side plate in the side of the immobile body 1, a controlling circuit substrate and an exterior recording medium reading device are made containable by providing an openable/closable space by a lid 8, and at the same time, in the front side surface a controlling panel 11 consisting of operation switches, etc., and an exterior recording medium inserting opening 12 are provided.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a laser beam that irradiates a photoreceptor with a light beam controlled by an image information signal and records characters or patterns on recording paper using an electrophotographic method. The present invention relates to image forming apparatuses such as printers, LCS printers, LED printers, and facsimile machines.

[Conventional technology]

Image formation in printers, copiers, etc., using a process in which an electrostatic latent image, formed on an electrophotographic photoreceptor through a charging and light exposure process, is visualized on recording paper through a development, transfer, and fixing process. The device is known.

An example of an image forming apparatus according to the prior art described above will be described below with reference to the drawings. FIG. 4 is a sectional view schematically showing the main parts of a conventional electrophotographic laser beam printer. In the figure, reference numeral 24 denotes a photosensitive drum in which a photoconductor is formed into a drum shape. When the photosensitive drum 24 is rotationally driven in the direction of arrow B, the drum surface is uniformly charged by the charging device 38. Next, an electrostatic latent image is formed by scanning image exposure with a laser beam modulated by an image signal, and when the electrostatic latent image passes through a developing device 130, it is converted into a CR image by toner. The toner image formed in this manner is transferred by the transfer device [51 onto a recording sheet that is fed from the paper feeding device 70 to the transfer position in synchronization with the toner image on the photoreceptor drum 24. After the transfer, the recording paper is separated from the drum and transferred to the fixing device f44.
After being fed into the recording paper, the conveying path of the recording paper is changed by approximately 180@, and the paper is discharged in a so-called face-down state to a paper discharge section 78 provided at the top of the main body of the apparatus. The conveyance route is shown by a broken line.

[Problem to be solved by the invention]

However, in the conventional image forming apparatus with the above configuration,
In order to achieve face-down paper ejection, the conveyance path after fusing is complicated and mechanical parts are required for that purpose. On the other hand, since the recording paper is suddenly bent and conveyed, the jam rate is high, especially for thick paper and envelopes. It was difficult to transport the paper, which caused the paper to wrinkle.

Furthermore, since the recording paper is bent in a preheated state immediately after passing through both the heating and pressure rollers that constitute the fixing device, paper curling occurs, which is particularly noticeable in cardboard and envelopes.

On the other hand, in the image forming apparatus according to the prior art, when the movable body part of the apparatus is expanded with respect to the stationary body as shown in FIG. 5 during maintenance such as processing of jammed paper and replacing consumables, The developing device 30 and the cleaning device 74, which are disposed at the front, are in a greatly tilted posture. For this reason, the toner in the developing device 30 and the cleaning device 74 moves and there is an unavoidable risk of leakage and scattering.

In addition, since the stock portion of the cassette, tray, etc. that stores the recording paper protrudes from the main body of the apparatus, there is a problem in that when the apparatus is installed on a desk or the like, the area occupied on the desk increases.

The present invention has been developed to solve these problems.The purpose of the present invention is to improve reliability by simplifying the paper conveyance path, reduce the desk space occupied by the device, and reduce paper jams and curls. It is an object of the present invention to provide an image forming apparatus which can easily handle paper even if it becomes jammed in a conveyance path.

[Means to solve the problem]

In order to solve the above-mentioned problems, the image forming apparatus of the present invention includes: a photoreceptor; an exposure means for forming image information as a latent image on the photoreceptor; a developing means for making the latent image visible;
An image forming apparatus that includes a transfer means for transferring the developed image onto recording paper and a fixing means for fixing the transferred developed image, and is expandable into at least two bodies, a stationary body and a movable body, The apparatus is characterized in that the transfer means is disposed laterally with respect to the photoreceptor and on the side of the movable body, and the recording paper discharge section is disposed at the bottom of the apparatus.

[For production]

With the above configuration, the present invention allows the conveyance path of the recording paper to be arranged substantially vertically.
It can be formed in a vertical direction, and by simplifying the path and downsizing the device, it is possible to reduce the area occupied on the desk, and even if recording paper becomes jammed in the machine, it can be easily removed.

Moreover, high accuracy can be maintained by arranging the photoreceptor, which requires positioning accuracy, and the image exposure device on the side of the stationary body of the main body.

(Example) The details of the present invention will be explained below based on the illustrated example.

Figures 1.2.3 are a perspective view and a cross-sectional view showing one embodiment of the present invention, and reference numeral 1 in the figure is a stationary body for the main body of the apparatus that houses the image forming mechanism, and when installed, it , a paper discharge port 3 for discharging the recording paper 73 from the paper discharge roller 2 is attached to the bottom of the side, and a movable body 4 is attached to the hinge so that it can be opened and closed, and side plates for supporting various units are installed on both sides of the interior. Furthermore, a cut sheet feeder 6 movable by guide mechanisms 7, 7 is provided at the upper part. Also, on the side of the stationary body 1,
In this embodiment, a space is provided on the right side as viewed from the front, which is separated by a side plate, and which can be opened and closed by a lid 8 to accommodate a control circuit board and an external recording medium reader. A control panel 11 and an external storage medium insertion slot 12 are provided.

On the front side of the stationary body 1, a recording paper guide plate 15 is disposed which is connected to a recording paper receptacle 14 whose upper end is expanded upward, and a gate roller 17 and a photoreceptor drum unit 18 are disposed in this order from above. Furthermore, a fixing device 44 is installed across a separating plate 43, which will be described later.
is installed.

A developing device 30 is disposed on the back side of the recording paper guide plate 15.

Around the photosensitive drum 24, a magnetic brush on the surface of the magnetic sleeve 35 of the developing device 3o is in contact with the photosensitive drum 24, and a charging device 38 is arranged at a constant interval from the bottom surface of the developing device 30 in the circumferential direction. Further, a static elimination lamp 39 is disposed upstream of this in the rotational direction.

Reference numeral 40 denotes an image exposure device, which is disposed in a rear space whose front and rear sides are shielded by a partition wall 41, and uses an optical system to pass a laser beam from the image exposure device through the window 41a1 of the partition wall 41 and the gap between the developing device 30 and the charging device 38 to the photosensitive drum. It is configured to irradiate the surfaces of 24.

A shielding plate 43 is provided below the photoconductor drum unit I 18, which slopes downward from the front side to the rear side and is integrated with the rear partition wall 41, dividing the main body space into two vertically. In the lower space, a fixing device 44 including a heating roller 45 and a pressure roller 47 and an exhaust fan 46 are arranged.

A heating roller 45 and a pressure roller 4 that constitute the fixing device 44
7 is disposed at a position where a line connecting these axes is substantially perpendicular to the leading edge of the recording paper discharged from the guide member 48.

A recording paper guide 48 is provided on the discharge side of the fixing device 44 to form a path for transporting the vertically moving recording paper 73 to the paper discharge port 3 via the paper discharge roller 2.

On the other hand, on the inner surface of the movable body 4, there is a recording paper detection lever 16 that operates a paper detector (not shown) from above, a pinch roller 50 that comes into contact with the gate roller 17, and a pinch roller 50 that faces the photosensitive drum 24 on the downstream side of the magnetic sleeve 35. In addition to disposing the transfer device 51, a guide member 52 consisting of a plurality of ribs with a concave center arranged in the width direction of the recording paper 73 is provided on the path from the photoconductor drum 24 to the fixing device 44. The recording paper 73 discharged from the body drum 24 is configured so that the movable body 4 side is convex.

6 is the above-mentioned cut sheet feeder installed on the upper part of the stationary body 1 by the parallel link machine $17, and the cut sheet feeder 6 is placed in front on the base 60 which can be set in two positions: the paper feeding position and the retracted position in an upright state. A recording paper hopper 63.6 is provided with a plurality of paper feed rollers 61.62 in parallel so as to be front and back, and the lower end of the recording paper 73 is brought into elastic contact with the paper feed rollers 61.62.
4 are erected, and guide members 65 and 66 extend from the lower ends of paper feed rollers 61 and 62 to the opening 14 on the main body side. Further, the receiver is provided with a manual feed port 68 at a position substantially above the port 14 by attaching guide members 67, 67 so as to be movable in the width direction. Note that reference numeral 69 in the figure indicates a locking member for fixing the base 60 to the stationary body 1.

In this embodiment, when the size of the recording paper 73 on which an image is to be formed is selected, one of the corresponding paper feed rollers 61 and 62, for example 62, rotates to feed one recording paper from the recording paper hopper 64. 73 is taken out and transferred to the stationary body 1 side by the guide 66. When the leading edge of the recording paper reaches the upper surface of the stationary body 1, the upwardly expanded receiver enters the opening 14, is guided by the guide plate 15, moves the stationary body 1 downward, and comes into contact with the gate roller 17. . At this stage, the recording paper 73 is further fed and bent, so that the recording paper detection lever 16 is pressed. As a result, a signal is output from the recording paper detector, and the gate roller 17 rotates to bring out the reference position of the recording paper 73, and then moves the recording paper 73 further downward.

On the other hand, data to be formed into an image is manually inputted to a control circuit board to control the image exposure device 40, and a latent image is formed on the photoreceptor drum 24 in accordance with the data. This latent image is formed on the photoreceptor drum 24.
As the toner rotates, toner is applied by the developing sleeve 35 and visualized.

This image development is performed by the transfer device 5 by rotation of the photoreceptor drum 24.
1, and the recording paper 7 located here
Transferred to 3.

The leading edge of the recording paper 73 that has exited the transfer device 51 is moved to the movable body 4.
as the image forming area expands, the back surface moves further downward along the guide member 52. In this manner, the toner enters the fixing device 44 while maintaining its curved state, and the toner adhering to the surface is fixed. As a result, the recording paper 73 is transferred to the fixing device 73 with the surface to which the unfixed toner is attached maintaining a gap from the side of the stationary body.
4, the toner is transferred to the fixing device 44 and fixed without rubbing the toner attached to the surface. The recording sheets 73 that have come out of the fixing device 44 are guided by a guide member 48 and are discharged and stacked face down from the paper discharge port 3 by the paper discharge roller 2 with the image forming surface facing downward.

As described above, in the paper conveyance path from feeding to paper ejection of the recording paper 73 according to this embodiment, the transfer position to the recording paper 73 is provided on the side of the photoreceptor drum 24, and the recording paper 73 is transferred to the side of the photoreceptor drum 24. The toner image is fed from above, transferred and fixed, and is ejected as printed pages onto a paper ejection tray 72 arranged in the direction of gravity through an ejection port provided at the bottom of the apparatus main body without bending the conveyance direction. Since it is a stacked path, face-down paper ejection is achieved without the need for complicated conveyance means or paths, and the space occupied by the desk for installing the device is reduced.

On the other hand, the exhaust heat of the fixing device 44 during the fixing process is absorbed by the shielding plate 4
3 prevents it from moving upward, and the fan 46 discharges it to the outside.

Also, among the toner that adhered to the photoreceptor drum 24 during the development process, the toner that was not transferred to the recording paper 73 is scraped off by the blade 25 located almost below the photoreceptor drum 24 and is transferred to the waste toner tank 26 directly below by gravity. be accommodated.

On the other hand, if a paper jam occurs during image formation, when the movable body 4 is opened, paper holding members such as the pinch roller 50, transfer device 51, recording paper guide member 52, etc. are removed from the stationary body 1 together with the movable body 4. Because of this, the recording paper conveyance path is opened at the front of the apparatus, and the recording paper 73 that is stopped midway through the conveyance path can be easily taken out.

When the removal of the recording paper 73 is completed, the movable body 4 is lightly returned to the stationary body 1 to enable the next image forming step J. Of course, when opening and closing this movable body, since the image exposure device 40 and the photosensitive drum 24 are stationary on the stationary body 1 side, the image exposure device 40 and the photosensitive drum 24 require precise positioning. This will not cause any positional deviation between the two.

In addition, when performing maintenance or adjustment of electrical devices such as control circuits, the electrical devices can be exposed simply by opening the side cover 8, making it possible to perform adjustment work while the image forming operation is being performed. This improves the efficiency of maintenance and inspection work.

Note that when forming an image on recording paper other than the recording paper stored in the recording paper hopper, set the guide members 67 and 67 to the width of the recording paper 73, and insert the lower end of the recording paper 73 into the manual feed slot 68. When inserted vertically, the recording paper 73 will be inserted into the recording paper tray
4, the recording paper detection lever 28 is actuated, and image formation is performed through the steps described above.

In this embodiment, the cut sheet feeder is connected to the stationary body of the main body by the fin, but the same effect can be achieved even if a guide groove or the like extending in the front and back direction is provided and guided by this. It is clear that it will play.

In addition, in this embodiment, a space is formed on the side of the stationary body of the main body, and the control section is housed in this space, but electrical devices such as the control section are housed in a separate case. It is clear that the same effect can be obtained even if this is attached to the side of the main body.

〔Effect of the invention〕

As described above, according to the present invention, there is provided a photoreceptor, an exposure means for forming image information as a latent image on the photoreceptor, a developing means for making the latent image visible, and a recording paper for producing the developed image. In an image forming apparatus that includes a transfer means for transferring the transferred image to a photosensitive member and a fixing means for fixing the transferred developed image, the image forming apparatus can be expanded into at least two bodies, a stationary body and a movable body. By arranging the recording paper on the side of the body and on the side of the movable body, and arranging the recording paper ejection section at the bottom of the apparatus, the recording paper conveyance path for face-down paper ejection can be simplified, and the mechanism By reducing the number of parts, the main body of the device can be made smaller and lighter, and the space it occupies on a desk when installed can be reduced.

Furthermore, since the paper path is not bent significantly, the occurrence of paper wrinkles, curls, etc. in cardboard, envelopes, etc. is suppressed, and the jam rate is reduced. Furthermore, even if recording paper should become jammed inside the machine, the interior can be opened by expanding the movable body relative to the stationary body, and the jammed paper can be easily removed.

A further advantage of the present invention is that the number of mechanical parts disposed on the movable body side is small, so the weight is reduced, and the swing support fulcrum of the movable body is provided at the bottom of the device. There is also no need for the Okawa-like damper mechanism that sometimes maintains that posture.

Furthermore, since the photoreceptor drum, developing device, cleaning device, and image exposure means are arranged on the stationary body side of the apparatus main body, a predetermined optical positional relationship is maintained, and the movable body can be expanded during maintenance and inspection. Even in this case, the developing device and cleaning device do not change their postures, so there is no fear of toner leaking and scattering. Moreover, as mentioned above, the movable body is lightweight and the image exposure means is disposed on the stationary body side.
Shocks and vibrations generated during engagement are minimal, reducing the risk of adverse effects on the imaging optical system, optical positional relationships, etc., resulting in good image formation with stable reliability and excellent operability over time. This has the effect that the device can be configured.

[Brief explanation of drawings]

FIG. 1 is a perspective view for explaining the appearance of an embodiment of the image forming apparatus of the present invention. FIG. 2 is a sectional view for explaining the image forming apparatus of the present invention. FIG. 3 is a sectional view for explaining a state in which the movable body of the image forming apparatus of the present invention is expanded with respect to the stationary body. FIG. 4 is a sectional view for explaining the prior art. FIG. 5 is a sectional view for explaining an expanded state of an image forming apparatus according to the prior art. 1... Stationary body 2... Paper ejection roller 4... Movable body 61゜70 ・ 71 ・ 72 ・ 73 ・ ・ ・ ・ ・ ・ Side plate ・ eφ・-Cut sheet feeder...External storage medium insertion slot -...Gate roller...Photoconductor drum unit...Photoconductor drum...Case cleaning blade ...Developing device...Charging device...Image exposure device...Partition wall...Shielding plate...Fixing device... - Fist Φ exhaust fan ... Transfer device 62 ... Paper feed roller ... Paper feed device ... Paper ejection section ... Paper ejection tray ... Recording Paper Figure 4 Figure 3 Figure 5

Claims (1)

[Claims] (1) A photoreceptor, an exposure means for forming image information as a latent image on the photoreceptor, a developing means for making the latent image visible, a transfer means for transferring the developed image onto recording paper, and a transfer means for making the latent image visible. A fixing means for fixing the developed image, and an image forming apparatus that can be expanded into at least two bodies, a stationary body and a movable body, wherein the transfer means is placed laterally with respect to the photoreceptor and An image forming apparatus characterized in that the recording paper ejecting section is disposed on the movable body side and the recording paper ejection section is disposed on the bottom of the apparatus.