JP2009042276A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus having structure which does not hinder attaching/detaching operation of a drawer part even when jamming occurs near a resist part. <P>SOLUTION: The image forming apparatus provided with the drawer part where a resist roller, a secondary transfer part, a conveyance part, a fixing device and a paper output roller can be integrally attached/detached is provided with notched parts 24a and 25a functioning as a guide on a front side plate 24 of a manual paper feeding unit part and a front side plate 25 of an image forming apparatus body. The apparatus is provided with the notched parts 24a and 25a, thereby preventing failure that paper (P') projecting from the area of an elastic sheet part in the vicinity of the resist part is caught by the side plate 24 on the front side of the manual paper feeding unit part and the front side plate 25 of the image forming apparatus body and then the operation of the drawer part can not be performed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and more particularly to an improved sheet conveying system.

  In Patent Document 1, the apparatus can be installed near the wall, and despite the fact that the apparatus can be installed near the wall, the entire apparatus can be downsized, the sheet can be smoothly conveyed, and the removal work can be easily performed when a jam occurs. In order to provide a highly reliable image forming apparatus capable of stably forming a high-quality image without sacrificing downsizing or jam processing efficiency, the first conveying means, the resist And a unit for pulling out a unit in which the unit and the main transport unit are integrated from the apparatus main body to the front of the apparatus main body, and the unit includes a first transport unit, a resist unit and a main transport unit provided on the frame. The drawer means is a rail provided on the apparatus main body and the frame, and slides the frame in the front-rear direction with respect to the housing of the apparatus main body. The positioning of the registration means and the photosensitive member is provided on the unit. And pins, the image forming apparatus for positioning in fitting the holes also provided in the housing of the apparatus main body is disclosed.

JP 2006-293397 A

  In a conventional image forming apparatus as disclosed in Patent Document 1, a registration unit, a secondary transfer unit, a conveyance unit, a fixing device, and a paper discharge unit can be integrally attached and detached, and a manual paper feed unit unit. In the configuration, when a jam occurs near the registration portion, the relay guide portion is automatically opened by the force of the solenoid, and the transfer paper is accommodated in the opened portion.

  However, when the transfer paper is large or thick, such transfer paper cannot be accommodated by the transfer paper storage unit alone, and the transfer paper that protrudes from the elastic sheet portion in the vicinity of the resist portion is a manual feed unit. The front side plate of the image forming apparatus and the front side plate of the main body of the image forming apparatus may be caught so that the operation of the drawer portion may not be performed.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a structure that does not hinder the attaching / detaching operation of the drawer portion even if a jam occurs near the resist portion.

  In the image forming apparatus according to the first aspect of the present invention, in the image forming apparatus in which at least the resist unit is configured to be detachable from the apparatus main body in a direction orthogonal to the sheet conveyance direction, the resist unit is clogged. A sheet shielding member for preventing the sheet from entering the apparatus main body is provided.

  According to a second aspect of the present invention, in the image forming apparatus of the first aspect, the paper shielding member is provided on the apparatus main body side.

  According to a third aspect of the present invention, in the image forming apparatus of the first aspect, the sheet shielding member is provided in the vicinity of the resist portion and is attached and detached together with the resist portion.

  According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects, the paper shielding member is provided in the vicinity of a paper conveyance guide of a paper feeding unit provided in the vicinity of the registration portion. It is characterized by that.

  According to a fifth aspect of the present invention, in the image forming apparatus according to the fourth aspect, the sheet shielding member and the sheet conveyance guide of the sheet feeding unit are formed of the same member.

  According to a sixth aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects, the sheet shielding member is made of metal.

  According to the seventh aspect of the present invention, in the image forming apparatus according to the sixth aspect, the sheet shielding member is composed of a plate-like member, and the thickness of the plate-like member is set to 0.6 to 1.6 mm. Features.

  According to the eighth aspect of the present invention, in the image forming apparatus according to any one of the first to seventh aspects, when the paper jammed in the registration unit is pulled out from the main body of the apparatus together with the registration unit, A notch for alleviating the interference is provided on the apparatus main body side of the portion where the interference occurs.

  According to the present invention, in an image forming apparatus having a configuration in which a registration unit, a secondary transfer unit, a conveyance unit, a fixing device, and a paper discharge unit are integrally removable, and a manual paper feed unit unit, Since the guide member is provided on the front plate of the adjacent image forming apparatus main body, the transfer paper that protrudes from the region of the elastic sheet portion in the vicinity of the resist portion is transferred to the front side plate and the main body front plate of the manual sheet feeding unit. It is possible to prevent a trouble that the user cannot catch the drawer and operate the drawer.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings.

  FIG. 1 is a schematic cross-sectional view showing a color image forming apparatus which is an example of an image forming apparatus which is an object of the present invention. In this apparatus, the image forming apparatus 1 is disposed substantially at the center, and the paper feeding section 2 is disposed immediately below the image forming section 1. The sheet feeding unit 2 includes a sheet feeding cassette 21 in each stage, but another sheet feeding device 22 can be added as necessary. Above the image forming unit 1, a reading unit 3 for reading a document is disposed. A recording medium (hereinafter referred to as paper) formed as a paper discharge storage section 4 on the left side of the image forming section 1 is discharged and stored.

  In the image forming unit 1, two image forming units 6... Are arranged around the belt-like intermediate transfer belt 5. In each image forming unit 6, a charging device 62 that charges the surface of the photosensitive member 61 around the drum-shaped photosensitive member 61, an exposure device 7 that irradiates the photosensitive member surface with image information with laser light, and a photosensitive member. Two developing devices 63 for visualizing the electrostatic latent image formed by exposure on the surface of the body 61 and a cleaning device 64 for removing and collecting the remaining toner on the photoconductor 61 are arranged. The intermediate transfer belt 5 rotates to form one color image.

  In this apparatus, first, development is performed with yellow (Y) toner in a yellow (Y) image forming unit, and the image is transferred to an intermediate transfer belt. Next, in the image forming portion of magenta (M), development is performed with magenta toner, and the image is transferred to the intermediate transfer belt. Next, in the cyan (C) image forming unit, the toner is developed with cyan toner, transferred to the intermediate transfer belt, and finally developed with black (BK) toner, and transferred to the intermediate transfer belt.

  A transfer device is provided for transferring the four color toner images transferred onto the intermediate transfer belt 5 to a sheet, and an intermediate transfer cleaning device is provided for removing and collecting toner remaining on the surface of the intermediate transfer belt 5 after transfer. Has been.

  A fixing device 8 for fixing the toner on the paper on which the toner image has been obtained is disposed on the downstream side of the image forming means (on the downstream side of the paper conveyance path). Then, the sheet that has passed through the fixing device 8 is discharged and stored in the discharge storage unit 4 by the discharge roller 41.

  At the time of double-sided printing, the paper conveyance path is branched by the branching unit 92, the paper is reversed via the double-sided device 93, the paper skew is corrected by the registration rollers 23 constituting the registration unit, and the back side image forming operation is performed. To.

  In the paper feed unit 2, unused paper is stored in the paper feed cassette 22, and the bottom plate that is rotatably supported raises the uppermost paper to a position where the pickup roller can contact. Due to the rotation of the paper feed roller, the uppermost paper is sent out from the paper feed cassette and conveyed to the registration roller 23. The registration roller 23 is controlled so as to start rotation at a timing so that the conveyance of the sheet is temporarily stopped and the positional relationship between the toner image on the surface of the photosensitive member 61 and the leading edge of the sheet becomes a predetermined position.

  In the reading unit 3, in order to perform reading scanning of a document (not shown) placed on the contact glass 31, reading traveling bodies 32 and 33 including a document illumination light source and a mirror reciprocate. Image information scanned by the reading traveling bodies 32 and 33 is read as an image signal into a CCD 35 installed behind the lens 34. The read image signal is digitized and subjected to image processing. Based on the image-processed signal, an electrostatic latent image is formed on the surface of the photoreceptor 61 by light emission of a laser diode LD (not shown) in the exposure device 7. The optical signal from the laser diode LD reaches the surface of the photoreceptor 61 via a known polygon mirror or lens. An automatic document feeder 3 for automatically feeding a document onto the contact glass 31 is attached above the reading unit 3.

  As described above, the color image forming apparatus of this example scans and reads a document, digitizes it, and copies it on a sheet of paper. The image forming apparatus can be configured as a multifunctional image forming apparatus having a facsimile function for exchanging information with a remote place and a so-called printer function for printing image information handled by a computer on paper. In that case, all the images formed by any function are discharged and stored in one discharge storage unit 4.

  In addition, when the paper is branched by the branching unit 92 and reversed through the double-sided device 93 and discharged from the paper discharge roller 41 through the reverse paper discharge roller, the paper stacked in the paper discharge storage unit 4 Is the state where the image surface is the bottom side, and even if the processing order of documents handled by copying, facsimile, and printer is performed from the first page, the first page is the top when taken out from the paper discharge storage section 4 It is freed from work such as aligning pages anew.

  As described above, an object of the present invention is to prevent an obstacle in the attaching / detaching operation of the drawer portion (H in FIG. 2) even when a jam occurs in the vicinity of the registration roller 23. In other words, the registration roller 23, the secondary transfer unit 51, the conveyance unit 52, the fixing device 8, and the paper discharge roller 41 can be integrated and removed as a drawer unit (indicated by symbol H in FIG. 2), and a manual paper feed unit unit (see FIG. In the configuration having the reference numeral A in FIG. 1, when a jam occurs in the vicinity of the registration roller 23, the relay guide portion (indicated by the reference symbol X in FIG. 3), the hatched portion in FIG. Is automatically opened by the power of the solenoid. As described above, the sheet is accommodated in this open portion (indicated by symbol P in FIG. 4). However, if the sheet is large or thick, it cannot be accommodated by the transfer sheet accommodating portion alone. Further, the sheet that protrudes from the region of the elastic sheet portion near the resist portion and sticks out to the front side plate of the manual sheet feeding unit and the front side plate of the image forming apparatus main body may be unable to operate the drawer portion H. (As shown in FIG. 5, indicated by the symbol P ′, the paper protrudes to the right side of the figure as shown).

  Therefore, as shown in FIG. 6 and FIG. 7, in the first embodiment of the present invention, in order to prevent damage to the cardboard when the jam occurs in the vicinity of the resist portion, and to prevent the drawer portion from being attached or detached. In addition, in the image forming apparatus in which the registration roller 23, the secondary transfer unit 51, the conveyance unit 53, the fixing device 8, and the paper discharge roller 41 are integrally attached and detachable, a front side plate of the manual sheet feeding unit A is provided. 24 and the front side plate 25 of the image forming apparatus main body are provided with notches 24a and 25a as guides. In FIG. 7, the front side plate 24 of the manual sheet feeding unit A is already cut out, and the front side plate 25 of the image forming apparatus main body is shown with hatched portions.

  The shape of the cutout portion 24a of the front side plate 24 of the manual feed unit A is preferably as large as possible, but is preferably determined in consideration of the balance of the strength of the manual feed unit A. The shape of the cutout portion 25a of the front side plate 25 of the image forming apparatus main body is preferably as large as possible as a countermeasure against catching, but due to the balance with other mechanical parts provided on the front side plate 25 of the image forming apparatus main body. It is preferable to determine.

  The operation of this embodiment will be described. By providing the notches 24a and 25a and extending the conveyance guide 28, the jammed paper is prevented from entering the space below the conveyance guide 28 and protrudes from the elastic sheet portion near the registration roller 23. This prevents the sheet (shown by P ′ in FIG. 5) from being caught on the front side plate 24 of the manual sheet feeding unit A and the front side plate 25 of the image forming apparatus main body, thereby making it impossible to operate the drawer H. It is. In the example of FIG. 7, the conveyance guide 28 extends downward from the notch 24a of the front plate 24 and serves as a shielding member. However, even if the conveyance guide 28 and the shielding member are attacked by separate members, Of course it is good.

  For comparison, FIG. 8 shows a perspective view of a conventional example corresponding to FIG. The sheet (P ′) protruding from the area of the elastic sheet near the registration roller 23 is caught on the front side plate 24 of the manual sheet feeding unit A and the front side plate 25 of the image forming apparatus main body, and the operation of the drawer H is performed. You can see how it can't be done.

  FIG. 9 shows a second embodiment of the present invention. The object of the present embodiment is to prevent troubles in the attaching / detaching operation of the drawer portion even if a jam occurs in the vicinity of the resist portion even in a large size paper. Therefore, in the manual feed unit portion A, the transfer paper shielding member 26 is provided below the conveyance guide portion.

  The operation of this embodiment will be described. Since the transfer paper shielding member 26 is provided in the lower part of the conveyance guide portion, even if the loop of the paper that protrudes from the region of the elastic sheet portion near the resist portion becomes large (indicated by P in FIG. 9), The paper P can be escaped in the direction of the arrow due to the influence of the shielding object 26, and can be prevented from being caught on the front side plate of the manual feed and by the operation of the drawer H. As the transfer paper shielding member 26, polyethylene terephthalate (PET) Mylar (trademark) having a thickness of 0.188 mm is attached to the manual feed unit. “Myla” is well known as a trade name of polyethylene terephthalate film manufactured by DuPont, USA, and is a very thin film material, which is transparent and non-flammable. It has characteristics such as good electrical insulation and resistance to acid. In this specification, “mylar” includes not only polyethylene terephthalate film manufactured by DuPont of the United States but also those having equivalent performance and properties. "

  In this embodiment, since the transfer paper shielding member 26 is provided, even if the loop of the paper P that protrudes from the area of the elastic sheet near the resist portion becomes large, the paper P is caught by the influence of the shielding. Can be prevented.

  FIG. 10 shows a third embodiment of the present invention. The object of the present embodiment is to prevent troubles in the attaching / detaching operation of the drawer H even if the paper is thick and a jam occurs in the vicinity of the resist portion.

  Therefore, a metal member having a thickness of 0.6 mm or more is used for the transfer material shielding member 26 described above. For this reason, even if the thickness of the paper increases and the catching force increases, the transfer material shielding member 26 has high rigidity, so that the transfer material shielding member 26 does not bend and a failure due to catching of the paper can be prevented.

  The transfer material shielding member 26 of this embodiment can be configured by caulking a SECC sheet metal having a plate thickness of 1.0 mm and a conveyance guide plate with burring caulking, for example.

  FIG. 11 shows a second embodiment of the present invention. The object of the present embodiment is to provide a structure that does not interfere with the attaching / detaching operation of the drawer portion H with an inexpensive configuration. For this reason, in this embodiment, the transport guide portion is provided with a portion (transfer paper shielding object) 27 that also functions as the transfer paper shielding portion 26. Therefore, the number of parts and the caulking process can be reduced, and the cost can be reduced. In addition, the hatching part of FIG. 11 is a shape part which integrated the conveyance guide and the transfer shielding part. The portion 27a indicated by the alternate long and short dash line has a conventional conveyance guide shape, and the portion below it has the shape of the shielding portion added in the present embodiment.

  If the transfer shield member is a metal member having a thickness of 0.6 mm or more, the transfer paper shield 27 has high rigidity even if the paper thickness increases and the hooking force increases. It is possible to prevent the trouble caused by the catching of the sheet 27 without bending.

  Although not shown in the drawings, when the present invention is applied to an electrophotographic copying machine, a laser beam printer, and a facsimile machine, the electrophotographic copying machine prevents an obstacle caused by catching of a sheet from the area of the elastic sheet portion near the resist portion. Thus, it is possible to prevent a failure due to catching of paper.

1 is a schematic cross-sectional view showing a color image forming apparatus that is an example of an image forming apparatus that is an object of the present invention The perspective view which shows the attachment or detachment operation | movement of a drawer part Side view showing the normal drawer state of the drawer Side view when the jam occurs Side view of the drawer with the same size paper or cardboard The side view which shows Example 1 of this invention The perspective view which shows Example 1 of this invention A perspective view showing a conventional example for comparison Side view showing Embodiment 2 of the present invention Side view showing Embodiment 3 of the present invention A perspective view showing Example 4 of the present invention.

Explanation of symbols

1: Image forming unit 2: Paper feeding unit 3: Reading unit 4: Paper discharge storage unit 5: Intermediate transfer belt 6: Image forming unit 7: Exposure device 8: Fixing device 21: Paper feeding cassette 22: Paper feeding device 23: Registration roller 24: Front plate of manual sheet feeding unit 24a: Notch 25: Front plate of image forming apparatus main body 25a: Notch 26: Transfer paper shielding member 27: Transfer paper shield 28: Conveyance guide 31: Contact glass 32, 33: Reading body 34: Lens 35: CCD
41: paper discharge roller 51: secondary transfer unit 52: transport unit 61: photoconductor 62: charging device 63: developing device 64: cleaning device 92: branching unit 93: double-sided device A: manual paper feed unit H: drawer unit LD: Laser diode X: Relay guide part P, P ': Paper

Claims (8)

  In an image forming apparatus configured to be attachable to and detachable from the apparatus main body at least in a direction perpendicular to the paper conveyance direction, a paper shielding member for preventing paper jammed in the registration section from entering the apparatus main body side. An image forming apparatus provided.   The image forming apparatus according to claim 1, wherein the sheet shielding member is provided on the apparatus main body side.   The image forming apparatus according to claim 1, wherein the sheet shielding member is provided in the vicinity of the resist portion and is attached and detached together with the resist portion.   4. The image forming apparatus according to claim 1, wherein the sheet shielding member is provided in the vicinity of a sheet conveyance guide of a sheet feeding unit provided in the vicinity of the registration portion. .   5. The image forming apparatus according to claim 4, wherein the sheet shielding member and the sheet conveyance guide of the sheet feeding unit are formed of the same member.   6. The image forming apparatus according to claim 1, wherein the sheet shielding member is made of metal.   The image forming apparatus according to claim 6, wherein the sheet shielding member is formed of a plate-like member, and a plate thickness of the plate-like member is set to 0.6 to 1.6 mm. 8. The image forming apparatus according to claim 1, wherein when the paper jammed in the registration unit is pulled out from the apparatus main body together with the registration unit, the part where the paper and the apparatus main body interfere with each other on the apparatus main body side. An image forming apparatus comprising a notch for reducing the interference.