This document claims priority to, and contains subject matter related to, Japanese Patent Applications No. 2004-271479, filed on Sep. 17, 2004, which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an image forming apparatus such as a copier, a laser beam printer, an LED printer and a facsimile using a belt unit. The present invention relates to an image forming apparatus including an intermediate belt unit that can be attached to and detached from a main body of the image forming apparatus.
2. Discussion of the Background
The use of various transfer components, including a transfer bet, to transfer an image in an image forming apparatus using an electrophotographic method, is well-known. Because such components are expendable supplies, transfer belts and related components are preferably accessible and/or removable from an image forming apparatus. Also, as known to all users of image forming devices, paper jams are possible, thus requiring improved paper flow designs and easy access to paper flow paths.
Japanese Patent Laid-Open No. 11-73035 describes an image forming apparatus that includes an intermediate transfer belt unit, which is removable from the apparatus along a rotational axis of the intermediate transfer belt. However, additional transfer elements are not easily accessed via an access plate and are not easily removable for component repair/replacement and paper jam clearing.
Japanese Patent Laid-Open No. 11-352741 describes an image forming apparatus that includes a first side plate, a second side plate, an image support body, a developing device and an intermediate transfer component. The image support body, the developing device and the intermediate transfer component are disposed between the first side plate and the second side plate and removable respectively. The image support body and the developing device are removable in a direction perpendicular to the side plates. The intermediate transfer component is removable in a direction perpendicular from a rotational axis of the intermediate transfer belt. However, the intermediate transfer component is not removable along a rotational axis of the intermediate transfer component. Also, additional transfer elements are not easily accessed via an access plate and are not easily removable for component repair/replacement and paper jam clearing.
Japanese Patent Laid-Open No. 2000-231321 describes an image forming apparatus that includes a transfer roller within an access component. However, this reference does not include an intermediate transfer device of any sort. Thus, this device also does not include a transfer device movement mechanism configured to move the transfer roller in and out of contact with an intermediate transfer device. Also, additional transfer elements are not easily accessed via an access plate and are not easily removable for component repair/replacement and paper jam clearing. Furthermore, this apparatus is not configured for color operations.
Thus, as discovered by the present inventors, what is desired is a construction that allows for easier access and removal of intermediate and other transfer devices.
It is a general object of the present invention to provide a belt unit in which one or more of the above-mentioned problems are eliminated.
A first object of the present invention is to provide an improved image forming apparatus including an intermediate transfer body unit which can be easily attached and detached from the image forming apparatus without abutting a surface of an image support body.
A second object of the present invention is to provide an improved image forming apparatus which can easily perform jam processing as necessary.
In order to achieve the above-mentioned objects, there is provided, according to one aspect of the present invention, an image forming apparatus including a housing, an image support body, a developing member, an intermediate transferring body, a transferring member, a cover member, and a transferring member moving mechanism. The intermediate transferring body is removable from inside of the housing to outside along the rotation axis of the intermediate transferring body. A transferring member transfers the image from the intermediate transferring body to a transferring material. A cover member supports the transferring member and opens and closes in the direction that is perpendicular to the rotation axis of the intermediate transferring body. A transferring member moving mechanism moves the transferring member between a first position where the transferring member contacts with the intermediate transferring body, and a second position where the transferring member is not in contact with the intermediate transferring body.
A third object of the present invention is to provide a novel method of attaching a transferring body to a housing of an image forming apparatus in a detachable manner.
In order to achieve the above-mentioned third object, there is provided, according to one aspect of the present invention, a method and apparatus for attaching a transferring body to a housing of an image forming apparatus in a detachable manner that includes steps and devices for inserting, positioning, closing, locking. Here, the transferring body is inserted into the apparatus along the rotation axis of the transferring body through an opening of the housing. The transferring body is then positioned in the housing. The opening of the housing is covered by a plate. The transferring body is locked with a first locking mechanism.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
The best mode for carrying out the invention is explained below with reference to the figures. The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the present invention.
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
A present embodiment is constituted as a full color printer using an intermediate transferring method.
Image forming elements, such as a charging device 4 configured to charge the photoconductor 1, a developing device 5 configured to develop a latent image on the photoconductor 1 by each color toner into a toner image, a cleaning device 2 for removing toner particles remaining on the photoconductor 1, are placed around the photoconductor 1 respectively. This image-forming unit preferably can serve as a process cartridge.
Though the components of the image forming units a, b, c and d is similar, the color of toner contained in each developing device 5 is magenta, cyan, yellow, black respectively, is different from each other. An exposing device 6 is disposed in the lower part from the image-forming unit. The exposing device 6 forms a latent image by irradiating a laser beam corresponding to each color image information in a surface of the photoconductor 1. Also, it is possible to adopt an exposing device including LED array and image forming mechanisms.
The intermediate transfer belt 11 includes a resin film or rubber substratum having 50-600 μm in thickness. The intermediate transfer belt 11 has a resistance value that enables a toner to transfer from photoconductor 1. As shown in
A cleaning device 15, having cleaning blade 16 configured to clean the toner and paper powders remaining on the surface of intermediate transfer belt 11, is disposed at a position opposed to the support roller 13 in the outside of the belt loop. The cleaning device 15 with the intermediate transferring device 10 is removal from the main body of the image forming apparatus as an intermediate transferring unit 20. A mechanism and a method of attachment and detachment are described below. In addition, of course, it is possible the cleaning unit 15 can be attached and detached from the intermediate transferring device 10 and the main body of the image forming apparatus.
In the drawings, a second transferring unit 30 is disposed in the right side of the intermediate transfer belt 11. A transfer roller 34, as a re-transfer member (second transferring member), configured to transfer the toner from the intermediate transfer belt 11 to a recording medium is disposed at the vicinity of the drive roller 12 supporting the 10 intermediate transfer belt 11 in the second transferring unit 30. When the image forming is not performed, the transfer roller 34 becomes to slightly separate from the intermediate transfer belt 11 as a normal position. On the contrary, when the image forming is performed, the transfer roller 34 is pressed to contact with the intermediate transfer belt 11 by pressing member. A mechanism of attachment and detachment of the transfer roller to the intermediate 15, transfer belt is described below.
Paper feeding cassettes 26-1, 26-2 including papers P as recording mediums are disposed in a paper supplying device at a lower part of the main body of the image forming apparatus.
A paper in the highest position of the paper feeding cassette is fed by a feeding device 20 including paper rollers 27, and guided by plural guide member 29 and 25, and transported to a resisting roller pair 28.
A fusing device 36 including a source of heat such as a heater is disposed at the upper part above the second transferring unit 30. An outputting guide 37 and an outputting roller 38 are placed behind the fusing device 36.
The second transferring cover 40 configured to support the second transferring unit 30 and to constitute a part of the main body has a structure that is possible to rotate and open around a shaft 24. When a paper jam occurs, the second transferring cover 40 is opened to remove the paper from a path of paper transportation easily.
An outputting stack portion 39 is formed on the top surface of the main body of the image forming apparatus.
A toner cartridge containing portion TS configured to contain four toner cartridges TC including supplying toner is disposed in the lower part of the outputting stack portion 39 and the upper part of the intermediate transfer belt 11. Colors of the toner of the toner cartridges TC are four colors of magenta, cyan, yellow and black, and the toner is supplied to a developing device 5 corresponding to color of the toner by a powder pump device (not shown).
A process for forming an image with the image forming apparatus constructed as above is explained below.
A signal for writing is sent by a host machine such as a computer. The exposing device 6 is driven based on a received image signal. A light from a laser light source (not shown) of the exposing device is scanned by a polygon mirror rotationally driven by a motor, and is irradiated to a photoconductor drum 1 uniformly charged with electricity with the charging device 4, through mirrors, to form a latent image corresponding to a writing information on the photoconductor drum 1.
The latent image formed on the photoconductor drum 1 is developed with the toner of the developing device 5, then, the toner image is formed and held on the surface of the photoconductor drum 1. The toner image is transferred from the photoconductor drum 1 to the surface of the intermediate transfer belt 11, which moves to synchronize with the photoconductor drum 1, by the first transferring roller 17.
After toner image transferring, the toner remaining on the surface of the photoconductor drum 1 is cleaned by the cleaning device 2. After that, the photoconductor drum 1 is neutralized by a charging neutralization device 3, and entered a standby state for next image producing cycle.
The intermediate transfer belt 11 moves to a direction shown in
When the toner image on the intermediate transfer belt 11 moves to a predetermined place, paper feeding is started. Paper rollers 27 rotate in the direction of the arrow. The paper in the highest position of the paper feeding cassette 26-1 or 26-2 is drawn by the feeding device including paper rollers 27, and the paper is transported to the resisting roller pair 28. The paper is fed from the resisting roller pair 28 so that a four-color overlaid toner image on the intermediate transfer belt 11 is transferred to a side of the paper P sent between the intermediate transfer belt 11 and the secondary transcription roller 34. An operation of the resisting roller pair 28 is controlled and/or timed so that the transfer media (e.g., paper) is presented to a nip position at roller 34 at the appropriate time.
In this embodiment, polarity of an electrostatic latent image formed in the surface of the photoconductor drum 1 is positive, and polarity of the toner formed on the photoconductor 1 is negative. The toner held on the photoconductor 1 is transferred to the intermediate transfer belt 11 by giving an electric charge larger than that of the latent image of the photoconductor 1 to the first transferring roller 17. In addition, the toner held on the intermediate transfer belt 11 is transferred to the paper P by giving an electric plus charge to the second transferring roller 34.
The paper P holding the toner image on the surface of itself as above is transported to the fixing device 36 and fixed. Then, the paper is transported through the outputting guide 37, and outputted to the outputting stack portion 39 by the outputting roller 38.
When the outputting stack portion 39 is constituted as
In this embodiment, the image is formed on only one side of the paper, but it is possible to constitute an image forming apparatus to form images on both sides of the paper by configuring the second transferring unit 30 as a second intermediate transfer belt. When images are formed in both sides of paper P, a four-color overlaid toner image formed as the first image carried on the surface of the intermediate transfer belt 11 is transferred to the second intermediate transfer belt 30 by the second transferring roller 34.
After that, while another four-color overlaid toner image is being formed as the second image on the intermediate transfer belt 11, the first image is transported to a transfer point by the second intermediate transfer belt 30.
The first image and the second image are transferred to the both sides of paper at the same time by taking timing of the intermediate transfer belt 11, the second intermediate transfer belt and the resisting roller pair 28.
The paper P holding the toner image on the both sides of surface of itself is transported to the fixing device 36 and the both images are fixed at the same time. Then, the paper is transported through the outputting guide 37, and outputted to the outputting stack portion 39 by the outputting roller 38.
In this embodiment, an image forming apparatus forms a color toner image by using a plurality of toner, but it is possible to constitute an image forming apparatus to form a monochrome image by using a black toner.
A way of attachment and detachment of the intermediate-transferring unit 20 from the main body of the image forming apparatus is explained as follows.
As shown in this figure, the frame of the main body includes a front faceplate 41, a rear faceplate 42, a side plate 43 configured to connect the front faceplate 41 and the rear faceplate 42, and a bottom plate 44.
In addition, a left guide rail 45 and a right guide rail 46 configured to support the intermediate transferring device 10 detachable are fixed between the front faceplate 41 and the rear faceplate 42. An upper opening 41a and a lower opening 41b are placed in the front faceplate 41.
The intermediate transferring unit 20 including the intermediate transferring device 10 and the cleaning unit 15, and each image forming unit SU can be attached to and detached from the main body of the image forming apparatus through the upper opening 41a.
A photoconductor fixing plate 47 configured to open and close the upper opening 41a is fixed to the front faceplate 41 and rotates around an axis. The paper feeding cassette 26-1, 26-2 can be attached to and detached from the main body of the image forming apparatus through the lower opening 41b.
A driving device 48 is attached to the rear faceplate 42. The driving device 48 includes motors and gear alignments configured to drive driving rollers of the photoconductor drum 1, the developing device 5 in the image forming unit SU and the intermediate transfer belt 11.
In this Figure, the frame of the main body is omitted for illustration purposes. The intermediate transferring unit 20 including the intermediate transferring device 10 and the cleaning unit 15 is supported by the guide rails 45, 46 in right and left, and is removable from the main body of the apparatus together. A pair of handles 23 is disposed on the top surface of the intermediate-transferring device 10. These handles 23 are capable of being folded. When the intermediate transferring device 10 or the intermediate transferring unit 20 is drawn from the main body of the image forming apparatus, the handles 23 can be held by hands by drawing them as shown in the
As mentioned before, the intermediate transferring device 10 (the intermediate transferring unit 20) is supported by the guide rails 45, 46 in right and left, and is removable from the main body of the image forming apparatus.
As shown in
As shown in
When the locking lever 52 is turned as shown in
In this state, the intermediate transferring device 10 (the intermediate transferring unit 20) can not be withdrawn from the main body of the image forming apparatus, because the triangle-shaped protruding portion 53a of the locking member 53 is locked in the rear faceplate 42.
In addition, when the locking lever 52 is in the locking released state as shown in
When the photoconductor fixing plate 47 is closed and the locking lever 52 is in the locked condition (so that the locking lever 52 is disposed in lengthwise direction as shown in
A rear protruding portion 53b of the locking member 53 and a sensor 54 are constituted to be able to detect that the intermediate transferring device 10 (the intermediate transferring unit 20) is inserted to the depths of the main body of the image forming apparatus, and it is locked. For example, a photo-interrupter having a light emitting member and a light receiving member can be used as the sensor 54.
In this example, the rear-protruding portion 53b of the locking member 53 is formed in the shape of a plate. In the locking released state as shown in
In addition to the constitution explained above, a microswitch and other sensing mechanisms could be adopted as the sensor.
In addition, a front cover (not shown) is installed in an outer casing of the image forming apparatus. When the front cover is opened, a front portion of the frame of the device is exposed, and operation of the locking lever 52 and opening of the photoconductor fixing plate 47 are enabled. In addition, exclusive doors can be provided with the outer casing corresponding to the locking lever 52 and the photoconductor fixing plate 47.
In this example, as mentioned before, the intermediate transferring device 10 and the cleaning unit 15 can be attached to and detached from the main body of the image forming apparatus together as the intermediate transferring unit 20. It is possible to constitute the cleaning unit 15 that can be removal from the main body of the image forming apparatus separately while the intermediate transferring device 10 is remaining in the main body of image forming apparatus. When the cleaning unit 15 can be detachable from the main body of the image forming apparatus independently of the intermediate transferring device 10, maintenance work becomes easier because a plurality of devices can be easily attached to and detached from the main body of the image forming apparatus. Often, the life of the cleaning member (for example, cleaning blade 16) is shorter than that of an intermediate transfer belt. Thus, with this embodiment, when the cleaning unit 15 reaches its life, it is not necessary to change the intermediate transferring unit 20 or the intermediate transferring device 10. When the cleaning unit 15 can be removed from the intermediate transferring device 10 after removing the intermediate transferring unit 20 from the main body of the image forming apparatus, the cleaning unit 15 is easily removed from the intermediate transferring device 10 by adopting the rail mechanism. In addition, because the attachment and detachment direction of the intermediate transferring unit 20 is parallel to a rotation shaft of the intermediate transfer belt 11, the constitution detachably supporting the intermediate transferring unit 20 (e.g., the guide rail) is simplified.
A mechanism of attachment and detachment of the second transferring unit 30 (the transfer roller 34) is explained next. As shown in
The mechanism for placing the second transferring unit 30 in and out of contact with the intermediate transferring unit 20 when the second transferring cover 40 is closed with cam member 60 and the second transferring unit removing lever 61 is shown in more detail in
It is also possible to adopt a reverse constitution that the motor 70 is energized in the non-image forming state and then the cam member 60 turns in a half round to remove the second transferring roller 34 from the intermediate transfer belt 11.
The construction of the present invention is not limited to the previously described and illustrated embodiments. For example, a tensioned shape of the intermediate transfer belt or the transportation belt (a transfer belt) may be used, with the constitution of the guide rail set appropriately. In addition, the cleaning device is not limited to a cleaning blade but may also include a cleaning roller or a cleaning brush. Also, alternative types of image forming units or fusing devices may be used.
The preceding apparatus may be a printer, a facsimile, a copier or another type of image forming apparatus.
Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.
Number | Date | Country | Kind |
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2004-271479 | Sep 2004 | JP | national |