JP2008000852A - Punching device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely drop punch chips to the lower part of a storage container, to be accumulated by eliminating static electricity directly from the punch chips that are generated by punching. <P>SOLUTION: In this punching device, a static eliminating member 160 made of a conductive member eliminating the static electricity charged in the punch chips that occur by punching is arranged in the movable region of a punch 64 for punching. The static eliminating member 160 consists of a ring body part 162 with an opening 161 in the central part, and a plurality of static eliminating needles 163 extended in prescribed length at prescribed intervals from the body part 162 towards the central part of the opening 161. The body part 162 of the static eliminating member 160 is fixed on the lower face side of a lower paper guide 62b in a state where the opening 161 is brought into line with through-holes 62a1, 62b1 of both paper guides 62a, 62b, and is grounded via a device frame. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a punch processing apparatus that is disposed as a paper post-processing step in the middle of a transport process for transporting printed paper to a stacking position of a discharge unit.

  In a conventional image forming apparatus, an image printing process on a conveyance sheet is performed by visualizing an electrostatic latent image formed on an electrostatic latent image carrier (photosensitive drum) using a developer (toner). By transferring the sheet to the transfer process at a timing when the leading end matches the leading end of the image information on the photosensitive drum, the image information is transferred onto the sheet by the transfer unit.

  In recent years, with the development of a color image forming apparatus and the increase in the printing processing speed of the image forming apparatus, an efficient transfer method is also required in the transfer process. Currently, there are methods such as “Corona charger”, “Roller transfer”, “Brush transfer”, “Belt transfer”, etc., which are widely used in the transfer process. A method is used in which a transfer electric field (approximately 1 to 3 kV) having a different polarity from the charged polarity of (toner) is applied, and a toner image electrically adsorbed on the surface of the photosensitive drum is transferred onto a sheet. . The paper to which such a transfer electric field is applied is charged by the electric field for transferring the toner image on the photosensitive drum onto the paper.

  Further, the conveyance paper is frictionally charged by rubbing with a plurality of conveyance rollers, paper guides and the like arranged from the paper feeding process to the discharge process, and the paper discharged after the printing process is finished is approximately 1 to 2 kV. It is common to have a level of static electricity. In addition, when a plurality of such electrostatically charged sheets are discharged to the discharge tray section, a repulsive electric field is generated between the sheets, which may cause a stacking defect in the discharge tray section.

  In order to solve such a problem, it has been proposed to dispose a static elimination brush composed of a conductive brush in the vicinity of the paper discharge roller (see, for example, Patent Document 1).

  In recent years, in order to reliably transport the transported paper to the transfer section in the transfer process, many apparatuses adopt a “belt transfer” system using a transfer belt. In the belt transfer method, an endless belt having a predetermined resistance value is bridged by a plurality of rollers, and a transfer area called a transfer nip is formed on the photosensitive drum between one of the bridged rollers or between the bridged rollers. is doing.

 In the belt transfer method for performing such a transfer process, the applied electric field applied to the transfer belt is larger than the conventional methods such as “corona charger”, “roller transfer”, and “brush transfer”. In other words, the “adsorption electric field” that attracts the conveyance paper to the transfer belt, the “transfer electric field” that is indispensable for the transfer process, and the paper that is peeled off from the transfer belt in order to smoothly convey the adsorbed and transferred paper to the next process. “Peeling electric field” is required.

  As described above, in the image forming apparatus adopting the belt transfer method in the transfer process, the transfer process is affected by the plurality of electric fields as described above, and receives frictional charge from the transport roller or the like in the transport path. Further, in the printing process mode (that is, the color printing process mode) in which two or more passes are required instead of one pass through the printing process, the influence of various electric fields as described above is affected by the transfer process and the transport. You will receive as many times as you pass the road.

  Table 1 shows the result of measuring the charge amount when the transported paper has finished the print processing step in such various print processing modes.

表１からも分かる通り、白印字やモノクロ印字に比べ、カラー印字では比較にならないほど多量の静電気が用紙中に蓄積されている。

As can be seen from Table 1, compared to white printing and monochrome printing, a larger amount of static electricity is accumulated in the paper than is possible with color printing.

  With respect to paper discharged in such a state, recent image forming apparatuses have many apparatuses that provide a post-processing step for printing paper as a multifunctional apparatus. In the post-processing step, stapling and punching, saddle stitching such as bookbinding, and filing are performed.

  Here, when the electrostatically charged paper is punched in the post-processing step as described above, punch scraps of the punched paper are generated. In this case, when the punch scraps are not charged with static electricity, the punch scraps fall naturally to the punch scrap storage container placed underneath due to their own weight, etc. It does not fall spontaneously inside and is adsorbed on the wall of the container by static electricity.

  FIG. 15 shows the state at this time. As shown in FIG. 15, when the punch scraps 130 are attracted to the full detection sensor 102 arranged on the container wall surface or the like, the full detection sensor 102 detects fullness even though the storage amount of the storage container 63 is not full. Such false detections frequently occur. Further, when the punch scraps 130 adsorbed to the container wall surface come into contact with each other, a blocking phenomenon (crosslinking phenomenon) may occur, and a void 150 may be generated in the storage container 63. In this case, there arises a problem that the fullness detection sensor 102 detects fullness before the proper storage amount (fullness) is reached due to the punch scraps 130 deposited thereon. In addition, there is a possibility that when the storage container is taken in and out, the punch scraps 130 charged with static electricity are scattered outside the container and adsorbed inside the apparatus.

  Therefore, techniques for solving such problems have been proposed (see, for example, Patent Documents 2 and 3).

Patent Document 2 describes that a punch waste container is vibrated by a punch waste vibration device to flatten mountain-shaped punch waste. Japanese Patent Application Laid-Open No. 2004-228688 also discloses a support means for supporting punch scrap stacking means for receiving punch scraps so as to move up and down, and detection for detecting a lowered position of the punch scrap stacking means that descends as the stack weight of punch scraps increases. And detecting that the punch scrap stacking means is full of punch scraps when the punch scrap stacking means is lowered to a predetermined position.
Japanese Patent Laid-Open No. 02-23384 Japanese Patent Laid-Open No. 11-255417 JP 2003-232671

  The techniques described in Patent Documents 1 and 2 and the like are effective techniques when the amount of frictional charge on the transport sheet is small, such as when the image forming apparatus is a low-speed machine or when the print processing mode is monochrome printing. That is, as described in the above prior art, a reasonable effect can be expected as a countermeasure when the triboelectric charge amount is about 1 to 2 kV.

  However, recent image forming apparatuses have been increased in speed as described above, and when the belt transfer method is adopted in the transfer process, as shown in Table 1, the electrostatic charge amount of the paper increases. Therefore, even if the punch waste storage container is vibrated as described in Patent Document 2, it is impossible to completely drop the punch waste adsorbed on the wall surface of the container.

  Further, according to the technique described in Patent Document 1, since the static eliminating brush is arranged on the downstream side of the paper discharge roller, the static electricity of the paper is removed when the paper is discharged to the paper discharge tray. However, when a post-processing step is added, the punch scraps are frictionally charged due to the strong shearing force generated by punching with a punch for punching. The problem of false positive detection remains.

  Further, according to the technique described in Patent Document 3, even if static electricity is charged to the punch scraps and adsorbed to the wall surface of the container, the weight of the punch scrap stacking means (punch scrap storage container) itself is substantially detected. Therefore, the false detection of fullness is eliminated. However, for that purpose, apart from the conventional full detection sensor, it is necessary to newly install a mechanism part that enables the punch scrap stacking means to move up and down, a detection sensor that detects the lowering of the punch scrap stacking means, The structure of the punching process is complicated, and there is a problem that the cost of parts is increased. Further, since the structure becomes complicated, there is a problem that there is a limit to downsizing of the apparatus.

  The present invention was devised to solve such problems, and the purpose of the present invention is to remove the static electricity directly from the punch waste generated by the punching process, thereby reliably dropping the punch waste to the lower part of the storage container. It is to provide a punch processing apparatus that can be deposited.

  In order to solve the above problems, the punch processing apparatus of the present invention is disposed in the middle of a transport process for transporting printed paper to the stacking position of the discharge unit, and performs punch processing on the transport paper using a punch for punching. In the punch processing apparatus to be performed, a neutralizing member for neutralizing static electricity charged in punch scrap generated by the punching process is disposed in a movable region of the punch for punching.

  More specifically, the static elimination member is composed of a main body having an opening, and a number of static elimination needles extending from the main body toward the center of the opening. The punch punch passes through the opening while pushing punch scraps after punching, so that the punch scraps, the punch for punch and the static elimination needle are in contact with each other.

  That is, the punch for punching is configured to perform punching by passing through a through hole formed in a paper guide constituting the paper transport path from above and descending, and the main body portion of the static elimination member is The through hole and the opening are fixed to the lower surface side of the paper guide. As a result, when the punch for punching is lowered, both the punch scrap punched out by the punch for punch and the punch punch are in contact with the static elimination needle, and not only the punch scrap but also the punch for punch are charged with static electricity. It is possible to remove static electricity.

  Thereby, since the punch waste punched out from the paper is surely neutralized, the punch waste can be naturally dropped into the punch waste storage container disposed below. In addition, since the punch for punching is neutralized, when the punch punch after punching passes through the punch hole of the paper and rises, the paper is not pulled to the punch punch side by the influence of static electricity, Occurrence of punch hole deformation or the like can also be prevented.

  Further, in the present invention, since the static elimination needle of the static elimination member is provided so as to project within the movable region of the punch for punch, the protruding length of the static elimination needle becomes a problem.

  That is, if the protruding length is long, the tip of the static elimination needle wound around the tip of the punch punch when the punch punch is lowered enters the space formed by the punch for punch and the punch die, There is a possibility of causing damage to the static elimination needle and malfunction of the punch processing apparatus. For this reason, it is preferable that the length of the discharge needle is such that the tip of the charge removal needle does not enter the space when the punch for punch descends to the lowest end and enters the punch die.

  Similarly, if the discharge needle has a long protruding length, the tip of the charge removal needle wound around the tip of the punch punch when the punch punch is raised, that is, the upper surface side of the lower paper guide constituting the paper transport path, that is, It will enter the paper transport path, which may cause damage to the static elimination needle, damage to the paper, and malfunction of the punch processing apparatus. For this reason, the protruding length of the static elimination needle is preferably set to a length that does not enter the upper surface side of the lower paper guide, that is, the sheet conveyance path.

  Further, as a problem when the length of the discharging needle is long, it is conceivable that when the punch punch is lifted, the discharging needle is caught in the rising and bent upward. As one method for solving such a problem, in the present invention, the static elimination needle is provided in a curved shape so that the tip portion hangs downward. Alternatively, the static elimination needle is provided so as to be inclined downward. By arranging in this way, even if the length of the static elimination needle is somewhat long, the contact operation between the static elimination needle and the punch for punch becomes smooth, and there is a problem that the static elimination needle is caught in the rise of the punch for punch by the contact pressure. Does not occur.

  In addition, the said static elimination member shall be earth | grounded via an apparatus frame.

  According to the punch processing apparatus of the present invention, the static electricity can be directly removed from the punch scraps by disposing the static eliminating member that neutralizes the static electricity charged in the punch scraps generated by the punch processing in the movable region of the punch for punching. Therefore, it is possible to reliably drop and deposit to the lower part of the storage container without scattering punch scraps.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention. In addition, the following embodiment is an example which actualized this invention, Comprising: The thing of the character which limits the technical scope of this invention is not.

[General configuration of MFP 1]
In the present embodiment, a case where an image forming apparatus including a punch processing apparatus according to the present invention is applied to a multifunction machine will be described. FIG. 1 shows an outline of the internal configuration of such a multifunction machine.

  As shown in FIG. 1, the multifunction machine 1 includes a scanner unit 2 as a document reading unit, an image forming unit 3, an automatic document feeding unit 4, and a sheet post-processing unit 5 as a sheet post-processing unit. ing. In the following, for the sake of convenience, a portion of the multi-function device 1 other than the paper post-processing unit 5 and the paper discharge tray 8 is referred to as an “apparatus main body”.

  The multifunction device 1 has a copier mode, a printer mode, and a FAX mode as image forming modes for forming an image on recording paper (including recording media such as OHP), and each mode is selected by a user. Hereinafter, each part of the multifunction device 1 will be described.

  First, the scanner unit 2 will be described. The scanner unit 2 creates document image data by reading an image of a document placed on a document table 41 made of transparent glass or the like, or an image of a document fed one by one by an automatic document feeder 4. It is a part to do. The scanner unit 2 includes an exposure light source 21, a plurality of reflecting mirrors 22, 23, and 24, an imaging lens 25, and a photoelectric conversion device (CCD; Charge Coupled Device) 26.

  The exposure light source 21 emits light to a document placed on the document table 41 of the automatic document feeder 4 or a document conveyed through the automatic document feeder 4. Each reflecting mirror 22, 23, 24 reflects the reflected light from the document once in the left direction in FIG. 1 and then reflects downward as indicated by the alternate long and short dash line A in FIG. Thereafter, the light is reflected in the right direction in FIG.

  There are the following two types of document image reading operations. When a document placed on the document table 41 is read (when used as a “sheet fixing method”), the exposure light source 21 and the reflecting mirrors 22, 23, 24 are arranged horizontally along the document table 41. By scanning, the image of the entire original is read. On the other hand, when reading a document conveyed by the automatic document feeder 4 (when used as a “sheet moving method”), the exposure light source 21 and the reflecting mirrors 22, 23, 24 are positioned at the positions shown in FIG. When the document passes through a document reading unit 42 of the automatic document feeder 4 described later, the image is read.

  The light reflected by the reflecting mirrors 22, 23 and 24 and passed through the imaging lens 25 is guided to the photoelectric conversion element 26, and the reflected light is converted into an electric signal (original image data) by the photoelectric conversion element 26. It is like that.

  Next, the image forming unit 3 will be described. The image forming unit 3 includes an image forming system 31 as a printing unit and a paper transport system 32.

  The image forming system 31 includes a laser scanning unit 31a and a photosensitive drum 31b as a drum type image carrier. The laser scanning unit 31a irradiates the surface of the photosensitive drum 31b with laser light based on document image data converted by the photoelectric conversion element 26 or image data input from an external terminal device or the like. The photosensitive drum 31b rotates in a direction indicated by an arrow in FIG. 1, and an electrostatic latent image is formed on the surface of the photosensitive drum 31b by being irradiated with laser light from the laser scanning unit 31a.

  In addition to the laser scanning unit 31a, a developing unit (developing mechanism) 31c, a transfer unit (transfer mechanism) having a transfer roller 31d, a cleaning unit (cleaning mechanism) 31e, not shown, are provided around the outer periphery of the photosensitive drum 31b. A charging unit (charging mechanism) having a static eliminator and a charging roller 31f is sequentially arranged in the circumferential direction.

  The developing unit 31c develops the electrostatic latent image formed on the surface of the photosensitive drum 31b into a visible image with toner (visualizing substance). The transfer roller 31d transfers a toner image formed on the surface of the photosensitive drum 31b onto a recording sheet as a recording medium. The cleaning unit 31e removes toner remaining on the surface of the photosensitive drum 31b after toner transfer. The static eliminator removes residual charges on the surface of the photosensitive drum 31b. The charging roller 31f charges the surface of the photosensitive drum 31b before the electrostatic latent image is formed to a predetermined potential.

  When forming an image on recording paper, the surface of the photosensitive drum 31b is charged to a predetermined potential by the charging roller 31f, and the laser scanning unit 31a applies laser light based on the document image data to the surface of the photosensitive drum 31b. Irradiate. Thereafter, the developing unit 31c develops a visible image with toner on the surface of the photosensitive drum 31b, and the toner image is transferred onto the recording paper by the transfer roller 31d. Further, after that, the toner remaining on the surface of the photosensitive drum 31b is removed by the cleaning unit 31e, and the residual charge on the surface of the photosensitive drum 31b is removed by the static eliminator. Thereby, one cycle of the image forming operation (printing operation) on the recording paper is completed. By repeating this cycle, it is possible to continuously form images on a plurality of recording sheets.

  On the other hand, the paper transport system 32 transports recording paper stored in a paper cassette 33 as a paper feeding unit or recording paper placed on the manual feed tray 34 one by one to form an image by the image forming system 31. At the same time, the recording paper on which the image has been formed is discharged to a paper discharge tray 8 as a paper discharge means via a paper post-processing section 5 described later. The paper discharge tray 8 is provided above the paper cassette 33 and below the scanner unit 2. Details of the paper discharge tray 8 will be described later.

  The sheet conveyance system 32 includes a main conveyance path 36 and a reverse conveyance path 37 in the apparatus main body, and a main conveyance path 51 and a switchback conveyance path 52 in the sheet post-processing unit 5 shown in FIG. The main conveyance path 36 of the apparatus main body and the main conveyance path 51 of the paper post-processing unit 5 are connected to each other with a discharge roller 36e of the apparatus main body as a boundary. The main conveyance path 51 and the switchback conveyance path 52 of the paper post-processing unit 5 will be described later. In the multi-function device 1, the recording paper is conveyed through the paper conveyance system 32 according to a so-called center reference. That is, the recording paper is conveyed with reference to the center position in the width direction (direction orthogonal to the recording paper conveyance direction).

  One end side of the main conveyance path 36 of the apparatus main body is branched into two, one branch end faces the discharge side of the paper cassette 33 and the other branch end is the discharge side of the manual feed tray 34. Opposite to. The other end side of the main transport path 36 faces the punch unit (punch processing device) 60 of the paper post-processing section 5. The reverse conveyance path 37 is connected to the main conveyance path 36 at one end side upstream (lower side in FIG. 1) from the position where the transfer roller 31d is disposed, and at the other end side than the position where the transfer roller 31d is disposed. It is connected to the main transport path 36 on the downstream side (upper side in FIG. 1).

  A pickup roller 36 a having a semicircular cross section is disposed at one branch end of the main conveyance path 36 (a portion facing the discharge side of the paper cassette 33). With the rotation of the pickup roller 36a, the recording sheets stored in the sheet cassette 33 can be intermittently fed to the main transport path 36 one by one. Similarly, a pickup roller 36b having a semicircular cross section is disposed at the other branch end of the main conveyance path 36 (a portion facing the discharge side of the manual feed tray 34). With the rotation of the pickup roller 36b, the recording paper placed on the manual feed tray 34 can be intermittently fed to the main transport path 36 one by one.

  A registration roller 36d is disposed upstream of the position where the transfer roller 31d is disposed in the main conveyance path 36. The registration roller 36d conveys the recording paper while aligning the toner image on the surface of the photosensitive drum 31b with the recording paper.

  A fixing unit 39 provided with a pair of heating roller 39a and pressure roller 39b for fixing the toner image transferred onto the recording sheet by heating, on the downstream side of the position where the transfer roller 31d is disposed in the main conveyance path 36. Is arranged. Further, at the downstream end of the main conveyance path 36, a discharge roller 36 e for discharging the recording sheet to the sheet post-processing unit 5 is disposed at the boundary with the main conveyance path 51 of the sheet post-processing unit 5.

  A branching claw 38 is disposed at a connection position at the upstream end of the reverse conveyance path 37 with respect to the main conveyance path 36. The branch claw 38 is a first position (a position indicated by a solid line) in FIG. 1 and a second position where the reversing conveyance path 37 is opened by rotating counterclockwise in FIG. 1 from the first position. It can freely rotate around the horizontal axis. When the branch claw 38 is in the first position, the recording paper is conveyed toward the main conveyance path 51 of the paper post-processing unit 5, and when it is in the second position, the recording paper can be supplied to the reverse conveyance path 37. ing.

  A conveyance roller 37 a is disposed in the reverse conveyance path 37, and when the recording paper switched back by the switchback conveyance path 52 in the paper post-processing unit 5 is supplied to the reverse conveyance path 37, The recording paper is conveyed by the conveying roller 37a, the recording paper is introduced into the main conveying path 36 on the upstream side of the registration roller 36d, and is again conveyed through the main conveying path 36 toward the transfer roller 31d. That is, an image can be formed on the back surface of the recording paper.

  Next, the automatic document feeder 4 will be described. The automatic document feeder 4 is configured as a so-called automatic duplex document feeder. The automatic document feeder 4 can be used as a sheet moving type, and includes a document tray 43 as an original placement unit, an intermediate tray 44, a document discharge tray 45 as a document discharge unit, and trays 43 and 44. , 45 is provided with a document conveying system 46 for conveying the document.

  The document transport system 46 includes a main transport path 47 for transporting a document placed on the document tray 43 to the intermediate tray 44 or the document discharge tray 45 via the document reading unit 42, and the document on the intermediate tray 44. And a sub-transport path 48 for supplying to the main transport path 47.

  A document pick-up roller 47a and a separating roller 47b are disposed at the upstream end of the main conveyance path 47 (a portion facing the discharge side of the document tray 43). Further, a separating plate 47c is disposed below the separating roller 47b. With the rotation of the document pickup roller 47a, one of the documents on the document tray 43 passes between the separation roller 47b and the separation plate 47c and is fed to the main conveyance path 47. Yes. PS rollers 47e and 47e are disposed on the downstream side of the joining portion (B portion in FIG. 1) of the main transport path 47 and the sub transport path 48. The PS rollers 47 e and 47 e adjust the leading edge of the document and the image reading timing of the scanner unit 2 and supply the document to the document reading unit 42. In other words, the PS rollers 47e and 47e temporarily stop the conveyance of the document while the document is supplied, adjust the timing, and supply the document to the document reading unit 42.

  The document reading unit 42 includes a platen glass 42a and a document pressing plate 42b. When the document supplied from the PS rollers 47e and 47e passes between the platen glass 42a and the document pressing plate 42b, the document reading unit 42 receives from the exposure light source 21. The light passes through the platen glass 42a and is irradiated on the original. At this time, the document image data is acquired by the scanner unit 2. A biasing force by a coil spring (not shown) is applied to the back surface (upper surface) of the document pressing plate 42b. Thereby, the document pressing plate 42b comes into contact with the platen glass 42a with a predetermined pressing force, and prevents the document from floating from the platen glass 42a when passing through the document reading unit 42.

  On the downstream side of the platen glass 42a, a conveyance roller 47f and a document discharge roller 47g are provided. The document that has passed over the platen glass 42a is discharged to the intermediate tray 44 or the document discharge tray 45 via the conveyance roller 47f and the document discharge roller 47g.

  An intermediate tray swinging plate 44 a is disposed between the document discharge roller 47 g and the intermediate tray 44. The intermediate tray swinging plate 44a swings between a position 1 shown in FIG. 1 and a position 2 flipped upward from the position 1 with the end on the intermediate tray 44 side being the center of swinging. It is possible. When the intermediate tray swinging plate 44 a is at the position 2, the document discharged from the document discharge roller 47 g is collected to the document discharge tray 45. On the other hand, when the intermediate tray swinging plate 44a is at the position 1, the document discharged from the document discharge roller 47g is discharged to the intermediate tray 44. When the sheet is discharged to the intermediate tray 44, the edge of the document is sandwiched between the document discharge rollers 47g and 47g. From this state, the document discharge roller 47g rotates in the reverse direction, so that the document is It is supplied to the conveyance path 48 and is sent out again to the main conveyance path 47 through the sub-conveyance path 48. The reverse rotation operation of the document discharge roller 47g is performed by adjusting the document delivery to the main conveyance path 47 and the image reading timing. Thus, the image on the back side of the document is read by the document reading unit 42.

[Outline of Paper Post-Processing Unit 5 and Discharge Tray 8]
Next, the paper post-processing unit 5 and the paper discharge tray 8 will be described.

  The paper post-processing unit 5 enables a plurality of paper post-processing such as punch processing and stapling processing on the recording paper discharged from the apparatus main body after completion of the printing processing. As described later, the sheet post-processing in the sheet post-processing unit 5 is performed when a request for sheet post-processing is made as a print condition when a print request is made.

  In this example, the sheet post-processing unit 5 and the paper discharge tray 8 are not provided outside the apparatus main body of the multifunction machine 1 but are provided using the space C formed by the apparatus main body. Specifically, in the apparatus main body of the multifunction machine 1, the paper cassette 33, the image forming unit 3 (image forming system 31), and the scanner unit 2 are arranged in a substantially “U” shape. The paper post-processing unit 5 and the paper discharge tray 8 are provided in a space “C” -shaped inside C formed by As a result, the sheet post-processing unit 5 and the paper discharge tray 8 can be installed in a limited space in the multifunction machine 1, and a plurality of sheet post-processing can be performed on the recording sheet. In addition, it is possible to reduce the space occupied by the multifunction device 1 including the paper post-processing unit 5 and save space. Further, since the sheet post-processing unit 5 has a plurality of functions and can perform a plurality of sheet post-processing, it has a functional aspect as compared with a case where a sheet post-processing unit capable of performing only a single sheet post-processing is provided. The sheet post-processing that can be selected by the user is increased, the convenience is improved, and the range of the user is expanded. Hereinafter, the paper post-processing unit 5 and the paper discharge tray 8 will be described in detail with reference to FIGS. The recording paper conveyance direction (direction shown in FIG. 3) is referred to as “paper conveyance direction”, and the recording paper width direction (direction shown in FIG. 3) orthogonal thereto is referred to as “paper width direction”.

  As shown in FIG. 2, the sheet post-processing unit 5 is disposed on the downstream side of the discharge roller 36e of the apparatus main body. The paper post-processing unit 5 includes a punch unit 60 having a punch hole punching function and a staple unit 70 having a staple function as paper post-processing units. The front surface (front surface) of the paper post-processing unit 5 is covered with an openable / closable cover 50. In the paper post-processing unit 5, the punch unit 60 is disposed on the upstream side, and the staple unit 70 is disposed on the downstream side. A paper discharge tray 8 is provided on the downstream side of the paper post-processing unit 5. The recording paper discharged from the discharge roller 36e is discharged to the paper discharge tray 8 through the punch unit 60 and the staple unit 70.

  As described above, in the paper post-processing unit 5, the punch unit 60 is disposed on the upstream side, and the staple unit 70 is disposed on the downstream side. The punch unit 60 performs punch punching processing for each recording sheet. In contrast, the stapling unit performs punching on a plurality of recording sheets. Instead of the punch unit 60 or the staple unit 70, a dummy unit having only a recording sheet conveying function may be provided. However, instead of providing the dummy unit in place of the staple unit 70, the paper discharge tray 8 may be arranged close to the upstream side. In this case, recording sheet switchback, which will be described later, is performed by a roller disposed at the most downstream side of the punch unit 60 (a roller disposed at a position facing the paper discharge tray 8).

[About schematic configuration of punch unit 60]
The punch unit 60 performs punching processing (punch processing) on the recording paper discharged from the discharge roller 36e. The punch unit 60 includes a punch hole punching mechanism 61, a guide plate 62, a punch waste storage container 63, and the like. A main transport path 51 is formed as the above-described paper transport system 32. The punch unit 60 is provided with a transport roller 56 in the middle of the main transport path 51. Note that the punch unit 60 is fixed to the apparatus main body, unlike a staple unit 70 described later.

  In the punch unit 60, when a print request is made, if there is a request for punch processing as a print condition, the recording sheet conveyed to the punch unit 60 is stopped at the position of the guide plate 62, and a punch hole is formed for each sheet. A punch hole is made by the opening mechanism 61. At this time, punch holes are formed at positions determined based on the print paper size.

  The punch hole punching mechanism 61 is arranged on the upper part of the punch unit 60, and the punch punching mechanism 61 is provided with a punch punch 64 having a diameter that matches the diameter of the punch hole along the sheet width direction. It is provided at two places at intervals. The punch punch 64 is provided so that it can be moved up and down. When the punch punch 64 is lowered, a punch hole is opened in the recording paper. Further, the punch punch 64 is provided so as to be able to reciprocate in a direction along the paper conveyance direction and in a direction along the paper width direction, and can be aligned when performing punch processing, as will be described later. Yes.

  The guide plate 62 is disposed below the punch hole punching mechanism 61, and the guide plate 62 is formed with an opening corresponding to a predetermined position for punch holes. The punch scrap storage container 63 is disposed below the punch unit 60 and collects punch scrap generated by punch punching processing by the punch scrap storage container 63. The punch waste storage container 63 is slidable along the paper width direction, and can be removed to the near side when the cover 50 is opened, as will be described later. Thereby, the punch scraps stored in the punch scrap storage container 63 can be taken out.

  When punching is performed by the punch unit 60, the punch punch 64 of the punch hole punching mechanism 61 is moved to a position corresponding to the position determined based on the above-described print paper size.

  In addition, the punch punch 64 of the punch hole punching mechanism 61 of the punch unit 60 is finely adjusted so that the punch hole can be accurately drilled at a position determined based on the printing paper size described above. I have to. This fine adjustment movement is performed by moving the punch punch 64 of the punch hole punching mechanism 61 forward, backward, left and right by a slight distance, and is performed in accordance with the passing position of the recording paper conveyed to the punch unit 60. . Specifically, a line sensor 36f that detects the leading and trailing edges of the recording paper that has passed through the fixing unit 39 and detects the side edge of the recording paper is provided on the upstream side of the discharge roller 36e. The line sensor 36f detects the position of the recording sheet conveyed to the punch unit 60 in the sheet conveying direction, and moves the punch punch 64 by a slight distance in the direction along the sheet conveying direction. Further, the position in the sheet width direction of the recording sheet conveyed to the punch unit 60 is detected by the line sensor 36f, and the punch punch 64 is moved to the left and right by a slight distance in the direction along the sheet width direction. .

  As described above, in the multi-function device 1, since the recording paper is conveyed with the center reference, the punch punch 64 of the punch hole punching mechanism 61 can be easily aligned. More specifically, the punch hole positions are usually two places symmetrical with respect to the center in the width direction of the recording paper. A high accuracy is required for the position of the punch hole in the width direction of the recording paper. Therefore, high accuracy is required also for the movement accuracy of the punch punch 64 of the punch hole punching mechanism 61. Therefore, in this example, the recording paper is conveyed with the center reference to detect the deviation of the conveyed recording paper with respect to the reference position at the center in the width direction, and the punch punching mechanism 61 punch punch according to the deviation. 64 is moved. Thereby, the accuracy of the punch hole position opened in the recording paper can be made high. Further, such alignment can be performed in the same manner for all sizes of recording paper to be conveyed.

[About the staple unit 70]
The staple unit 70 performs a staple process on the recording paper conveyed from the upstream punch unit 60. As will be described later, the staple unit 70 is provided so as to be slidable in the direction along the sheet conveyance direction when the cover 50 is opened. Further, as will be described later, the staple unit 70 is detachably provided with respect to the punch unit 60 disposed on the upstream side of the staple unit 70.

  The staple unit 70 includes a staple mechanism unit 71, a staple table 72, an alignment plate 73, a paper discharge roller 74, and the like. Further, as the above-described paper transport system 32, a main transport path 51 and a switchback transport path 52 are formed. At the connection position between the downstream side of the main conveyance path 51 and the upstream side of the switchback conveyance path 52, a branching claw 53 for switching the direction in which the recording paper is guided and a discharge roller 54 for discharging the recording paper to the staple table 72 are provided. It has been. A switchback roller 55 is provided on the downstream side of the switchback conveyance path 52.

  In the stapling unit 70, when a stapling process is requested as a printing condition at the time of a printing request, the stapling mechanism unit 71 performs stapling processing on a predetermined number of recording sheets stacked on the stapling table 72. At this time, stapling is performed at a position determined based on the print paper size and the desired staple position. The desired stapling position is a position where the user performs a stapling process desired by the user, such as one stop at the upper left corner of the recording paper or two stops at the left end.

  The staple mechanism unit 71 is disposed below the discharge roller 54 and binds the rear end portion of the recording paper stacked on the staple table 72 with a staple needle. The stapling mechanism unit 71 is configured to be capable of reciprocating along the paper width direction, and can perform stapling processing at a position determined based on the above-described printing paper size and desired stapling position. . When stapling is performed by the staple unit 70, the staple mechanism unit 71 is moved to a position corresponding to a position determined based on the above-described print paper size and desired staple position.

  The staple table 72 is used for stacking the recording sheets discharged from the discharge roller 54 and serves as a processing table for staple processing by the staple mechanism unit 71. The staple table 72 is disposed with the downstream side in the paper transport direction inclined upward. When the stapling process is performed, the recording paper discharged from the discharge roller 54 slides down to the upstream side in the paper conveyance direction along the inclination of the staple table 72 due to its own weight. On the other hand, when the stapling process is not performed, the recording sheet is discharged from the discharge roller 74 to the discharge tray 8 as described later.

  The alignment plate 73 is disposed to face both sides in the direction along the paper width direction of the upper surface (surface on which the recording paper is discharged) of the staple table 72. The pair of alignment plates 73 are provided so as to be capable of reciprocating along the paper width direction. When the stapling process is performed by the staple unit 70, the alignment plate 73 is moved along the sheet width direction so that the alignment in the sheet width direction is performed for each recording sheet discharged onto the staple table 72. I have to. At this time, the alignment plate 73 is moved in accordance with the movable width determined based on the printing paper size, that is, based on the size of the recording paper to be conveyed.

  The pair of alignment plates 73 can be reciprocated by, for example, a rack and pinion mechanism. Specifically, the rack member connected to one alignment plate 73 and the rack member connected to the other alignment plate 73 are arranged to face each other with a predetermined interval. A pinion gear is arranged between the rack members and meshes with the rack members. Here, both rack members are provided so as to be able to reciprocate along the paper width direction, whereas the pinion gear is provided so as not to move. The pair of alignment plates 73 are moved symmetrically with each other along the paper width direction by rotating the pinion gear by transmitting power from the drive source. Thereby, it is possible to align the recording sheets discharged onto the staple table 72 in the sheet width direction.

[About the discharge roller 74]
The paper discharge rollers 74 are arranged in a pair of upper and lower sides so as to face the paper discharge tray 8 on the most downstream side in the paper conveyance direction of the staple table 72, and discharge the recording paper on the staple table 72 to the paper discharge tray 8. Is. As will be described later, the paper discharge roller 74 is also used as a shifter roller for sorting and discharging the recording paper to the paper discharge tray 8. The upper and lower paper discharge rollers 74 are both provided as drive rollers. That is, the upper and lower paper discharge rollers 74 are both connected to the drive source.

  Further, the upper and lower paper discharge rollers 74 are provided so as to be able to come into contact with and separate from each other. It is provided to be movable. When the recording paper is discharged to the paper discharge tray 8, the upper and lower paper discharge rollers 74 are pressed against each other. On the other hand, when the stapling process is performed on the recording paper, the upper and lower paper discharge rollers 74 are separated from each other. State. Note that the home positions of the upper and lower discharge rollers 74 are positions where they are in pressure contact with each other.

  By providing the upper and lower paper discharge rollers 74 so as to be able to contact and separate, there are the following advantages. When performing the stapling process, the upper and lower paper discharge rollers 74 are separated from each other so that the leading end of the recording paper fed to the staple table 72 protrudes from between the upper and lower paper discharge rollers 74. As a result, the length of the staple table 72 in the direction along the paper conveyance direction can be shortened, and the staple unit 70 can be made compact. After the stapling process, the upper and lower discharge rollers 74 are brought into a pressure contact state, and the recording sheet bundle after the stapling process is discharged to the discharge tray 8. As a result, it is not necessary to provide a mechanism for discharging the recording paper bundle after the stapling process to the paper discharge unit, for example, a mechanism for pushing out the recording paper bundle.

  Here, the shifter process by the paper discharge roller 74 will be described. In this example, the recording paper is shifted by the paper discharge roller 74 so that the recording paper is sorted and discharged to the paper discharge tray 8.

  In the shifter process, recording paper is discharged from a plurality of positions along the paper width direction to the paper discharge tray 8, and the recording paper discharge position on the paper discharge tray 8 is shifted in the direction along the paper width direction for recording. This sorts paper. Such shifter processing can be performed, for example, by providing the upper and lower discharge rollers 74 so as to be able to reciprocate in the axial direction (direction along the paper width direction). Specifically, the upper and lower paper discharge rollers 74 are moved in the axial direction while the recording paper is chucked by the upper and lower paper discharge rollers 74. As a result, the recording paper chucked by the upper and lower paper discharge rollers 74 moves along the paper width direction. When the recording paper is discharged to the paper discharge tray 8 at that position, the recording paper discharge position on the paper discharge tray 8 can be shifted in the direction along the paper width direction. In this way, for example, sorting can be performed for each number of copies of the recording paper, so that the last page of the first set and the first page of the second set are not discharged to the same position on the discharge tray 8. Can do. Further, by using the paper discharge roller 74 as a shifter roller, it is possible to reduce the number of members and the cost. After the recording paper is discharged, the upper and lower paper discharge rollers 74 are returned to their original positions.

  As described above, since the upper and lower paper discharge rollers 74 are provided so as to be able to contact and separate, the following advantages are obtained. Conventionally, when the paper discharge roller is also used as a shifter roller, the shifter process is not performed when the staple process is performed. In other words, since the paper discharge roller was not able to contact and separate, the shifter function by the paper discharge roller corresponds to only one recording paper that has not been stapled, and the recording paper bundle that has undergone stapling processing. Was not compatible. On the other hand, in this example, after the stapling process, the upper and lower discharge rollers 74 are brought into a pressure contact state, whereby the recording sheet bundle after the stapling process can be surely chucked, and the shifter process is performed in this state. be able to. As a result, the shifter process can be similarly performed on a single recording sheet that has not been stapled or a recording sheet bundle that has been stapled.

[Slide of staple unit 70]
Here, the movement of the staple unit 70 in the direction along the paper conveyance direction will be described. In this example, the staple unit 70 is configured to reciprocate along the paper transport direction together with a paper discharge tray 8 and a bottom 89 below the paper discharge tray 8 described later. The direction in which the staple unit 70 is slid may be a direction along the paper width direction.

  A slide-type rail 75 is provided between the lower portion of the staple unit 70 and the exterior 90 of the apparatus main body. The slide rail 75 can be, for example, a slide rail using a ball bearing such as Acculide (registered trademark). Specifically, the slide-type rail 75 is configured such that a holding member for holding a ball bearing is interposed between a rail attached to the lower portion of the staple unit 70 and a rail attached to the exterior 90 of the apparatus main body. Then, the rail on the staple unit 70 side slides through the ball bearing with respect to the rail on the exterior 90 side of the apparatus main body, so that the staple unit 70 can smoothly slide with respect to the apparatus main body.

  Normally, the staple unit 70 is disposed so as to contact the punch unit 60 fixed to the apparatus main body. On the other hand, when a jam occurs in the main transport path 51 or the switchback transport path 52, or when replacing or replenishing staples, the staple unit 70 is slid downstream in the paper transport direction. By this slide, as shown in FIG. 7, a space is formed between the staple unit 70 and the punch unit 60. Thereby, visibility improves and it becomes possible to put a hand in this space and to work. As a result, the recording paper jammed in the main transport path 51 or the switchback transport path 52 can be easily taken out, and the jam processing operation can be easily performed. In addition, it is possible to easily replace and replenish the staple needle.

  At this time, the distance that the staple unit 70 can slide to the downstream side in the paper conveyance direction is the maximum distance that the end of the staple unit 70 on the downstream side in the paper conveyance direction does not protrude from the side surface of the multifunction device 1. . That is, the staple unit 70 is slidable as long as the end portion on the downstream side in the paper transport direction does not protrude from the apparatus main body. As described above, the range in which the staple unit 70 can slide is limited so that the slide rail 75 is not deformed.

  As described above, the staple unit 70 is normally disposed so as to be in contact with the punch unit 60 fixed to the apparatus main body. At this time, as shown in FIG. 8A, the staple unit 70 is engaged with the engagement groove 66 provided in the punch unit 60 by the hook 76 provided in the staple unit 70, so that the punch unit 60 is fixed. The hook 76 is provided so as to be rotatable around a rotation fulcrum 76a. Further, the hook 76 is biased in a direction of rotating clockwise about the rotation fulcrum 76a. The front end portion 76 b of the hook 76 is formed in a substantially L shape so as to engage with the engagement groove 66. The other end side of the hook 76 is connected to the hook lever 77.

  In order to slide the staple unit 70 to the downstream side in the paper conveyance direction, the following operation is performed. By operating the hook lever 77 and rotating the hook 76 counterclockwise around the rotation fulcrum 76a against the urging force, the engagement between the hook 76 and the engagement groove 66 is released. . Thereby, the staple unit 70 can be moved to the downstream side in the paper transport direction. By moving the staple unit 70 to the downstream side in the paper conveyance direction, it is possible to easily perform a jam processing operation or the like as described above.

  On the other hand, in order to fix the staple unit 70 to the punch unit 60 after finishing the jam handling operation and the like, the following is performed. When the staple unit 70 is slid toward the upstream side in the paper conveyance direction and brought closer to the punch unit 60, the tip 76b of the hook 76 comes into contact with the inclined surface 66a of the engagement groove 66 as shown in FIG. . From this state, by further sliding the staple unit 70 to the upstream side in the sheet conveyance direction, the hook 76 is opposed to the urging force 76a against the urging force as shown in FIG. 8C. Rotate clockwise. Further, by sliding the staple unit 70 to the upstream side in the sheet conveying direction, the hook 76 gets over the apex 66b of the engaging groove 66, and the hook 76 is engaged with the engaging groove 66 as shown in FIG. Match. As a result, the staple unit 70 is fixed to the punch unit 60, and the staple unit 70 cannot be moved downstream in the paper transport direction. The staple unit 70 may be provided with an engaging groove, and the punch unit 60 may be provided with a hook.

[About cover 50]
As described above, the cover 50 is provided so as to be openable and closable on the front surface of the paper post-processing unit 5. The cover 50 is pivotable about a pivot shaft 50a provided at the lower end thereof. As shown in FIGS. 3 to 5, when the cover 50 is closed, the cover 50 is disposed vertically to cover the front side surface of the sheet post-processing unit 5. On the contrary, as shown in FIGS. 6 and 7, when the cover 50 is opened, the cover 50 is disposed substantially horizontally to open the front side of the sheet post-processing unit 5. As described above, when the cover 50 is opened, the punch waste storage container 63 can be taken out to the front side, and the punch waste in the punch waste storage container 63 can be disposed of.

  The cover 50 is formed in a rectangular shape when viewed from the front, and is sized to cover the entire front surface of the punch unit 60 and the staple unit 70. The cover 50 is formed with a protrusion 50 b that protrudes toward the back side (inside the paper post-processing unit 5). When the cover 50 is closed, the protrusion 50 b is formed in the staple unit 70. The cover 50 is fixed to the paper post-processing unit 5 by engaging with the hole 70b. Further, the outer edge of the cover 50 is also formed with a protrusion protruding toward the back side. When the cover 50 is closed, the protrusion of the cover 50 is in contact with the end of the front surface of the punch unit 60 and the staple unit 70. Abut. Among these, the protrusion 50 c formed at the end on the staple unit 70 side is provided as a restriction protrusion for restricting the position of the staple unit 70.

  The restricting protrusion 50 c comes into contact with a restricting groove portion 70 c formed at the upstream end of the front surface of the staple unit 70 in the sheet conveying direction. As shown in FIG. 9, the restricting protrusion 50c is formed in parallel with a direction (indicated by a one-dot chain line in FIG. 9) in which the contact surface 50d with the restricting groove 70c is in the paper width direction in a plan view. However, it is inclined at an angle α with respect to the direction along the paper width direction. In this way, the width in the direction along the paper conveyance direction of the regulation protrusion 50c is formed so as to become gradually narrower toward the leading end side (toward the inner side of the paper post-processing unit 5). On the other hand, the contact surface 70d on the regulation groove portion 70c side of the staple unit 70 is formed in parallel to the direction along the paper width direction in plan view.

  Providing the cover 50 with the restricting protrusion 50c as described above has the following merit. As described above, the staple unit 70 is detachably attached to the punch unit 60. The hook 76 of the staple unit 70 is engaged with the engagement groove 66 of the punch unit 60, so that the staple unit 70 is fixed to the punch unit 60. At this time, the boundary surfaces 60f and 70f are opposed to each other. However, since the tip 76b of the hook 76 gets over the apex 66b of the engagement groove 66 and engages the hook 76 with the engagement groove 66, a gap is generated between the boundary surfaces 60f and 70f. .

  In this example, the staple unit 70 is slid to the upstream side in the sheet conveying direction, the hook 76 is engaged with the engagement groove 66, the staple unit 70 is fixed, and then the cover 50 is closed. In this case, when the cover 50 is rotated and closed, the restriction protrusion 50 c of the cover 50 comes into contact with the restriction groove portion 70 c of the staple unit 70. Further, when the cover 50 is closed, the contact position between the restricting protrusion 50c and the restricting groove portion 70c gradually moves toward the near side along the inclination of the contact surface 50d of the restricting protrusion 50c. Thereby, the staple unit 70 is pressed against the punch unit 60 side. Then, when the protrusion 50b described above is engaged with the engagement hole 70b and the cover 50 is completely closed, the boundary surface 70f of the staple unit 70 approaches the boundary surface 60f of the punch unit 60 to a position substantially free of gaps, In this state, the staple unit 70 is fixed.

  In this way, by providing the restricting protrusion 50c that contacts the end of the staple unit 70 when the cover 50 is closed, a gap generated between the staple unit 70 and the punch unit 60 when the cover 50 is closed is provided. It can be as small as possible. Thereby, the fixing position of the staple unit 70 can be regulated, and vibration of the staple unit 70 can be prevented.

  The cover 50 is provided so as to serve as a switch for switching on / off the operation of the multifunction device 1. The operation of the multi-function device 1 is the operation of each part of the multi-function device 1 during printing processing, paper post-processing, etc. When the cover 50 is closed, the operation of the multi-function device 1 is turned on, and during printing processing, Various processes such as post-processing are allowed and possible. On the contrary, when the cover 50 is open, the operation of the multifunction device 1 is turned off, and various processes such as the printing process and the paper post-processing are prohibited and impossible. In this way, the operation of the multifunction device 1 is switched on / off in accordance with the opening / closing of the cover 50. Further, when the print request is made, if the cover 50 is open, the user is prompted to close the cover 50.

  By providing such a cover 50 serving as an on / off switch in the paper post-processing unit 5, the cover 50 can be used as in the case of jam processing, staple needle replacement, replenishment, or the like. In the open state, printing processing, paper post-processing, and the like are not performed. Thereby, the safety of the multi-function device 1 including the paper post-processing unit 5 can be ensured.

  In addition to the cover 50, the multifunction machine 1 is provided with a door that opens and closes. Therefore, in a state where all the doors of the multifunction device 1 including the cover 50 are closed, the operation of the multifunction device 1 is turned on, and any of the doors of the multifunction device 1 including the cover 50 is opened. The operation of the machine 1 may be turned off.

[Conveying the recording paper in the paper post-processing section 5]
Next, conveyance of the recording paper in the paper post-processing unit 5 will be described. As described above, the paper post-processing section 5 is formed with the main transport path 51 and the switchback transport path 52.

  The main conveyance path 51 is formed from the discharge roller 36e of the apparatus main body to the discharge roller 54 disposed in the middle of the staple unit 70 through the punch unit 60. Along the main conveyance path 51, the recording paper after completion of the printing process discharged from the discharge roller 36 e of the apparatus main body is conveyed to the staple table 72 or the switchback conveyance path 52 of the staple unit 70. When the punching process is selected as the printing condition at the time of the print request, the recording sheet conveyed to the main conveyance path 51 is stopped on the guide plate 62 after the double-sided printing process or the single-sided printing process is completed. Then, the punch punch 64 of the punch hole punching mechanism 61 is lowered to open a punch hole at a predetermined position at the rear end of the recording paper.

  The switchback conveyance path 52 is formed in the upper portion of the staple unit 70 and is formed from the discharge roller 54 to the switchback roller 55. In the switchback conveyance path 52, when the recording paper is conveyed from the discharge roller 54 to the switchback roller 55, the switchback roller 55 rotates in the reverse direction with the rear end portion of the recording paper chucked by the switchback roller 55. As a result, the recording sheet is reversed, and this time, the recording sheet is conveyed from the switchback roller 55 to the discharge roller 54.

  The switchback conveyance path 52 is used when printing processing is performed on both sides of the recording paper. That is, when performing double-sided printing in the multi-function device 1, the recording paper that has been printed on the front surface is guided from the main transport path 36 of the apparatus body to the switchback transport path 52 via the main transport path 51, and this switchback. It is reversed in the conveyance path 52. Then, the reversed recording sheet is conveyed from the switchback conveying path 52 to the main conveying path 36 of the apparatus main body via the main conveying path 51, and further guided to the inverting conveying path 37 to be placed on the back surface of the recording sheet. The printing process can be performed. The recording paper on which the printing process on the back surface has been completed is discharged from the discharge roller 36e of the apparatus main body to the staple table 72 of the staple unit 70 through the main conveyance path 51.

  On the other hand, when the printing process is not performed on both sides of the recording sheet, that is, when the printing process is performed only on one side of the recording sheet, the recording sheet on which the printing process on the front side is finished is transferred from the main conveyance path 51 The sheet is discharged from the discharge roller 54 to the staple table 72 as it is without being conveyed to the switchback conveyance path 52.

  As described above, when the switchback conveyance path 52 is provided in the staple unit 70 and the recording paper is switched back in the switchback conveyance path, the switchback is performed by the roller for discharging the recording paper to the paper discharge tray 8. Compared to the above, the transport distance of the recording paper is shortened. Therefore, it is possible to improve the printing efficiency of the multifunction machine 1 when performing double-sided printing.

Further, in this example, a conveyance path such as the main conveyance path 51 and the switchback conveyance path 52 is not formed between the discharge roller 54 and the staple table 72, and the recording paper is slackened from the discharge roller 54. It is discharged in the state. For this reason, if the switchback is performed while the recording paper is chucked by the discharge roller 54, the recording paper may be wrinkled. Therefore, in this example, the recording paper is not switched back by the discharge roller 54, but the switchback conveyance path 52 is provided to prevent the recording paper from being wrinkled. In addition,
The switchback conveyance path 52 is not formed in the punch unit 60 disposed upstream of the staple unit 70. As described above, the punch hole punching mechanism 61 is disposed above the punch unit 60. Because it is.

  The recording paper conveyance as described above is arranged at a connection position between the downstream side of the main conveyance path 51 and the upstream side of the switchback conveyance path 52 (a branch position between the main conveyance path 51 and the switchback conveyance path 52). This is made possible by the turning operation of the branching claw 53. The branching claw 53 is a first position (a position indicated by a solid line) in FIG. 2, and a second position (a position indicated by a solid line) that rotates clockwise from FIG. 2 to open the switchback conveyance path 52 ( (Position indicated by a two-dot chain line). When the branching claw 53 is in the first position, the recording paper can be discharged toward the staple table 72, and when it is in the second position, the recording paper can be conveyed to the switchback conveyance path 52. Yes. The first position is the home position of the branching claw 53.

  When single-sided printing processing is selected as a printing condition at the time of printing request, the branching claw 53 is in the first position, and the recording paper after the front surface printing is guided to the staple table 72. On the other hand, when a double-sided printing process is selected as a printing condition at the time of a printing request, the branching claw 53 is moved from the first position after the leading edge of the recording paper on which printing on the front surface has passed passes through the fixing unit 39. Switch to the second position. As a result, the recording sheet after the front surface printing is guided to the switchback conveyance path 52. Further, after the leading end of the recording paper on which the printing process on the back surface has passed passes through the fixing unit 39, the branching claw 53 is switched from the second position to the first position. As a result, the recording sheet after the reverse side printing is guided to the staple table 72.

  Furthermore, when the print request is made and the staple processing is selected as the print condition, when the recording paper is discharged toward the staple table 72, after the trailing edge of the recording paper is separated from the discharge roller 54, The branching claw 53 at one position is swung. By repeating such swinging of the branching claw 53 several times, the rear end portion of the recording paper that is separated from the discharge roller 54 and falls onto the staple table 72 is hit downward. As a result, the recording paper quickly reaches the staple table 72.

  As described above, when the stapling process is performed, the recording sheet discharged to the staple table 72 slides down to the upstream side in the sheet conveyance direction along the inclination of the staple table 72 by its own weight. At this time, if the next recording sheet is discharged while the recording sheet is slipping down and the two recording sheets overlap, the lower recording sheet may not slide further. Therefore, after the recording paper slides down to the end of the staple table 72, the next recording paper is discharged to the staple table 72. For this reason, the printing efficiency of the multifunction device 1 becomes worse as the recording paper takes longer to slide down to the end of the staple table 72. Therefore, in this example, the time until the recording paper slides down to the end of the staple table 72 is shortened as much as possible by swinging the branching claw 53 and hitting the rear end of the recording paper. The printing efficiency is improved.

  The recording paper discharged from the discharge roller 54 toward the staple table 72 gradually comes into contact with the staple table 72 from the front end. While the recording sheet is being discharged from the discharge roller 54, the leading end of the recording sheet reaches the discharge roller 74 on the most downstream side of the staple table 72. Subsequent conveyance of the recording paper differs depending on whether or not stapling is performed by the staple unit 70.

  When the stapling process is not performed, since the upper and lower paper discharge rollers 74 are in a pressure contact state, the recording paper is sent by the paper discharge roller 74 and discharged to the paper discharge tray 8. At this time, when a shift request is requested as a print condition at the time of a print request, the recording sheet is discharged to the discharge tray 8 after the shift process by the discharge roller 74 described above.

  On the other hand, when performing stapling, the upper and lower paper discharge rollers 74 are in a separated state. For this reason, the recording paper is not sent by the discharge roller 74 even if the leading end of the recording paper is sent between the upper and lower discharge rollers 74 by the discharge roller 54. Therefore, when the trailing edge of the recording sheet moves away from the discharge roller 54 and loses the conveying force to the downstream side in the sheet conveying direction, the recording sheet is now upstream in the sheet conveying direction along the inclination of the staple table 72 due to its own weight. Slide down. As a result, the sheet conveyance direction is aligned with the recording sheet.

  Then, after a predetermined number of recording sheets are discharged from the discharge roller 54 and aligned and stacked on the staple table 72, the staple mechanism unit 71 performs stapling on the rear end of the recording sheet. During this stapling process, the middle portion of the recording paper is between the upper and lower paper discharge rollers 74 in the separated state. After the stapling process is completed, the upper and lower paper discharge rollers 74 are pressed against each other, and the paper discharge rollers 74 are driven to discharge the recording paper bundle to the paper discharge tray 8. At this time, when a shift request is requested as a print condition at the time of a print request, the recording sheet is discharged to the discharge tray 8 after the shift process by the discharge roller 74 described above.

  Here, as described above, since the upper and lower paper discharge rollers 74 are both provided as drive rollers, there are the following advantages. In this example, the bundle of recording sheets after the stapling process is discharged by the discharge roller 74. In this case, if only one of the discharge rollers 74 is a driving roller and the other is a driven roller, the recording sheet bundle is discharged. As the number of sheets increases, the rotation of the driving roller is less likely to be transmitted to the driven roller. As a result, the recording paper may be torn at the position where it is bound by the staple needle. On the other hand, by using both the upper and lower paper discharge rollers 74 as drive rollers, the recording paper can be smoothly discharged to the paper discharge tray 8 without being damaged.

[About the output tray 8]
Next, the paper discharge tray 8 will be described.

  The paper discharge tray 8 is provided together with the above-described paper post-processing unit 5 in the space “C” -shaped inside formed by the main body of the multifunction device 1. A recording sheet that has been subjected to sheet post-processing such as punching and stapling in the sheet post-processing unit 5 is discharged to the sheet discharge tray 8. The paper discharge tray 8 is provided so as to extend and contract along the paper transport direction (recording paper discharge direction). Moreover, it is provided so that raising / lowering is possible up and down. Further, it is slidable with respect to the apparatus main body.

  As shown in FIGS. 3 and 5, the paper discharge tray 8 is formed as a tray that can be expanded and contracted in one to three stages in the direction along the sheet conveyance direction. In this example, the paper discharge tray 8 is configured so that the user can manually expand and contract along the paper transport direction according to the print paper size.

  The paper discharge tray 8 includes a first paper discharge tray 81, a second paper discharge tray 82, and a third paper discharge tray 83. The first paper discharge tray 81 is the largest tray and is disposed closest to the paper post-processing section 5. The first paper discharge tray 81 is formed in a length that does not protrude from the side surface (side wall) of the multifunction machine 1. The first paper discharge tray 81 is provided so as not to move in the direction along the paper transport direction.

  The second paper discharge tray 82 is an intermediate size tray and is stored in a storage portion 81 a formed in the first paper discharge tray 81. The second paper discharge tray 82 is provided so as to be movable back and forth in the direction along the paper transport direction. The third paper discharge tray 83 is the smallest tray and is stored in a storage portion 82 a formed on the second paper discharge tray 82. The third paper discharge tray 83 is provided so as to move forward and backward in the direction along the paper transport direction.

  As shown in FIG. 3, in a state where the paper discharge tray 8 is contracted to only one stage, the length of the paper discharge tray 8 in the direction along the paper transport direction is minimum, and the third paper discharge tray 83 is All the sheets are stored in the second sheet discharge tray 82, and all the second sheet discharge trays 82 are stored in the first sheet discharge tray 81. At this time, the length of the paper discharge tray 8 in the direction along the paper conveyance direction is equal to the length of the first paper discharge tray 81 in the direction along the paper conveyance direction, and does not protrude from the side surface of the multifunction device 1. . In this way, by preventing the paper discharge tray 8 from protruding from the apparatus main body in the most contracted state, the paper discharge tray 8 can be stored in the space of the apparatus main body when the multifunction device 1 is not used. To be able to.

  On the other hand, as shown in FIG. 5, in the state where the paper discharge tray 8 is extended in three stages, the length of the paper discharge tray 8 in the direction along the paper transport direction is the maximum, and the first discharge The second paper discharge tray 82 protrudes to the maximum from the paper tray 81, and the third paper discharge tray 83 protrudes to the maximum from the second paper discharge tray 82. At this time, the length of the paper discharge tray 8 in the direction along the paper transport direction is longer than the length of the maximum size recording paper that can be printed by the multifunction device 1 in the paper transport direction. As a result, when the paper discharge tray 8 is extended to the maximum length, even a maximum-size printable recording sheet can be stably stacked. As will be described later, the paper discharge tray 8 can be slid together with the stapling unit 70. However, even if the paper discharge tray 8 is slid in a state where recording paper is stacked, the recording paper is removed from the paper discharge tray 8. It will not fall.

  As described above, since the paper discharge tray 8 is provided so as to be extendable and retractable in the direction along the paper conveyance direction, the paper discharge tray 8 can be adjusted to an optimum length according to the print paper size. .

  As shown in FIGS. 3 and 4, the paper discharge tray 8 is formed as a tray that can be moved up and down. In this example, the paper discharge tray 8 is configured to move up and down according to the amount (number of sheets) of recording paper to be stacked.

  The amount of recording paper discharged to the paper discharge tray 8 is detected by an upper limit sensor 84 provided in the vicinity of the lower paper discharge roller 74. The upper limit sensor 84 is provided as a contact type sensor. When the uppermost surface of the recording paper loaded on the paper discharge tray 8 reaches a predetermined height, the upper limit sensor 84 is turned on. Thereby, the fullness of the paper discharge tray 8 is detected. Then, the paper discharge tray 8 is lowered by a predetermined distance by this full detection. As the discharge tray 8 is lowered, the upper limit sensor 84 is turned off. In this way, the amount of recording paper loaded on the paper discharge tray 8 is detected by switching the upper limit sensor 84 on / off. In this example, the home position of the paper discharge tray 8 is the highest position (the position shown in FIG. 3) of the paper discharge tray 8, and the upstream end of the paper discharge tray 8 is disposed directly below the paper discharge roller 74. ing. The discharge tray 8 is gradually lowered as the amount of recording paper loaded increases. The upper limit sensor 84 may be provided as an optical sensor.

  As described above, the paper discharge tray 8 is provided so as to be extendable and contractible. However, the first paper discharge tray 81 is moved up and down during the up-and-down movement, so that the second paper discharge tray 8 and the second paper discharge tray 81 are moved in the second direction. The paper discharge tray 82 and the third paper discharge tray 83 are configured to move up and down.

  For example, the first sheet discharge tray 81 is raised and lowered as follows. A drive unit 85 for moving the first paper discharge tray 8 up and down is provided on the back side of the first paper discharge tray 81. The drive unit 85 accommodates a drive belt (not shown), and the drive belt can be driven by a drive power supply (not shown) connected by a wiring 86. A support member that supports the leading end of the first paper discharge tray 81 is connected to the drive unit 85. The support member is provided to reciprocate up and down by driving the drive belt. Then, the power of the drive belt of the drive unit 85 is transmitted to the first paper discharge tray 81 through such a support member, and thereby the first paper discharge tray 81 moves up and down. An arm 88 that supports the first paper discharge tray 81 is provided below the first paper discharge tray 81. The arm 88 is disposed between the first paper discharge tray 81 and the bottom 89. The arm 88 is bent in an L shape, and its bending angle is variable. The bending angle of the arm 88 changes according to the raising / lowering position of the first paper discharge tray 81. A protrusion is provided at the end of the first paper discharge tray 81 near the paper post-processing section 5. This protrusion engages with a groove extending in the up and down direction provided in the sheet post-processing section 5 and can slide in the groove.

  As described above, the discharge tray 8 can be moved up and down and the home position is set to the highest position, thereby providing the following advantages. When the distance between the upper and lower sides of the paper discharge tray 8 and the paper discharge roller 74 (the recording paper discharge position to the paper discharge tray) becomes long, the recording paper is discharged so as to fall into the paper discharge tray 8, so that stacking performance is improved. Deteriorate. However, in this example, the distance between the top and bottom of the paper discharge tray 8 and the paper discharge roller 74 is made as short as possible by lowering the paper discharge tray 8 from the highest position according to the amount of recording paper to be stacked. Thus, the stacking property of the recording paper discharged to the paper discharge tray 8 is kept good. Then, by lowering the paper discharge tray 8, a certain amount of recording paper can be secured, and the space of the apparatus main body can be used effectively.

  Further, when the home position of the discharge tray 8 is set to a position below the highest rise position, the discharge tray 8 is moved to the highest rise position every time the multifunction device 1 is started up from the above-described stacking property. It is necessary to increase the printing speed, which delays the first copy and may reduce the printing efficiency. However, in this example, since the home position of the paper discharge tray 8 is set to the highest position, there is no need for such an increase, so that the first copy is not delayed, and a decrease in printing efficiency can be prevented.

  As described above, the discharge tray 8 can be moved up and down, and a space C <b> 1 is formed between the bottom portion 89 below the discharge tray 8. As shown in FIG. 3 and the like, the back side of the space C1 is shielded by the drive unit 85 and the like described above, whereas the near side and the side surface of the space C1 are open. For this reason, in this space C1, for example, recording paper taken out from the paper discharge tray 8 after printing, recording paper to be supplied next to the paper cassette 33, and a toner container to be replaced next are stored. Could be placed. However, if the paper discharge tray 8 is lowered while such an object is placed, there is a possibility of damaging the paper discharge tray 8 or its driving unit 85 or destroying the placed object. Therefore, in this example, the front side and the side surface side of the space C1 below the paper discharge tray 8 are covered with shielding members 91 and 92, respectively. 1 and 3 to 7, the shielding members 91 and 92 are omitted.

  The shielding member 91 provided on the front side of the space C <b> 1 has an upper end fixed to the front side portion of the first paper discharge tray 81 and a lower end fixed to the bottom 89. Further, the shielding member 92 provided on the side surface side of the space C <b> 1 has its upper end fixed to the tip side portion of the first paper discharge tray 81 and its lower end fixed to the bottom 89.

  In this example, since the paper discharge tray 8 is provided so as to be able to move up and down, the shielding members 91 and 92 are provided so as to expand and contract in accordance with the up and down movement of the paper discharge tray 8, respectively. As the extendable shielding members 91 and 92, for example, an accordion curtain type or a shutter type is used.

  Thus, the lower portion of the paper discharge tray 8 is covered with the shielding members 91 and 92 so that the space C1 formed below the paper discharge tray 8 is not opened. Accordingly, it is possible to prevent an object from being placed in the space C1. Therefore, when the paper discharge tray 8 is lowered, the paper discharge tray 8 is not damaged or the placed object is not broken. .

  As shown in FIG. 7, the paper discharge tray 8 is slidable with respect to the apparatus main body. In this example, the paper discharge tray 8 is configured to reciprocate along the paper transport direction together with the bottom 89 and the staple unit 70. The direction in which the paper discharge tray 8 is slid may be a direction along the paper width direction.

  A bottom portion 89 below the paper discharge tray 8 is not fixed to the apparatus main body and is connected to the staple unit 70. As described above, since the staple unit 70 is slidable with respect to the apparatus main body, the bottom 89 is slidable together with the staple unit 70. The bottom 89 is connected to the paper discharge tray 8 via the arm 88, the shielding members 91 and 92, and the paper discharge tray 8 slides together when the bottom 89 slides. A slide rail may be provided between the bottom 89 and the exterior 90 of the apparatus main body.

[Detailed Configuration of Punch Unit (Punch Processing Apparatus) 60 According to the Present Invention]
Next, in the image forming apparatus having the above-described configuration, the configuration of the punch unit (punch processing device) 60 that is a feature of the present invention will be described in more detail with reference to FIGS.

  FIG. 10 is a partially enlarged schematic cross-sectional view showing a more detailed configuration of the punch unit 60.

  In the figure, the horizontal arrow indicates the paper conveyance direction of the paper conveyance path formed by the upper and lower paper guides 62a and 62b. In this figure, the printed paper is conveyed from the right side to the left side. The paper for which the “punch processing” function is selected in the print processing request is subjected to print processing by the image forming unit and then discharged to the paper discharge unit through the paper transport path in the figure. The sheet that has reached the unit 60 uses the line sensors (light emitting element 36f1 and light receiving element 36f2) 36f disposed immediately before the punch unit 60 to detect the conveyance position in the sheet width direction (perpendicular to the sheet surface) and to detect the sheet. Trailing edge detection is performed. By detecting the trailing edge of the transport sheet in this way, the stop timing of the transport sheet is calculated, the appropriate position in the direction along the sheet transport direction of the punching process is determined, and the transport stop timing of the sheet is determined. .

  Next, based on the detected value in the paper width direction, appropriate positions of the punch die 65 and the punch punch 64 constituting the punch unit 60 are determined, and the punch die 65 and the punch punch 64 are moved. Done. This moving operation is alignment for determining the punching position in the paper width direction, and is as important as the direction along the paper conveyance direction. In other words, the alignment is indispensable for improving the stacking property when filing the punched paper and improving the appearance of the paper bundle. The punching die 65 and punching punch 64 used in the present embodiment are configured to be exchangeable for a 2-hole and a 3-hole, and can be appropriately replaced according to the user's selection. It has become.

  The punch punch 64 has an upper end connected to a rotary cam (eccentric cam) 67. The punch cam 67 is rotated by driving a drive source (not shown) to rotate the rotary cam 67. Yes. In this case, by rotating the punch shaft 67a 180 degrees from the home position (position shown in FIGS. 11A and 11B), the punch punch 64 is reciprocated one up and down so that punching is performed. It has become. FIG. 11C shows a state in which the punch shaft 67a is rotated 90 degrees from the home position, and the punch punch 64 has a through hole 62a1 formed in the upper paper guide 62a constituting the paper transport path and the lower paper. It passes through the through hole 62b1 formed in the guide 62b from the top to the bottom and reaches the lowest end. FIG. 11 (d) shows a state where the punch shaft 67a is further rotated 90 degrees in the same direction from the state shown in FIG. 11 (c), and the punch for punch 64 is the through hole 62b1 of the lower paper guide 62b. And, it passes through the through hole 62a1 of the upper paper guide 62a from the lower side to the upper side and returns to the home position. In the punching process, the state shown in FIG. 11B to the state shown in FIG. Note that such a punching operation is a conventionally known operation, and thus a detailed description thereof is omitted here.

  That is, with respect to the paper P stopped at an appropriate position with respect to the punch unit 60 (the state shown in FIG. 11B), the punch shaft 67a is rotationally driven by the drive source to rotate the rotary cam 67 by 180 degrees. The punch 64 is reciprocated one up and down to form a punch hole P1 at a specified position of the paper P. The paper P on which the punch hole P1 is formed is re-conveyed to the next process (discharge tray section) by a control unit (not shown) that recognizes that the formation of the punch hole has been completed.

  On the other hand, the punch scraps 130 formed as punch holes fall into the punch scrap storage container 63 disposed below via the auxiliary die guide plate 68 disposed below the lower paper guide 62b. The punch waste storage container (hereinafter simply referred to as “storage container”) 63 is provided with a full detection sensor 102 that detects the storage amount of the punch waste 130 to be stored. The full detection sensor 102 may be a mechanical sensor, but in the present embodiment, a reflective optical sensor is used. That is, the reflecting plate 102c is arranged on one upper inner wall of the storage container 63, two openings are formed on the other upper inner wall opposite to the reflecting plate 102c, and the light emitting element (light emitting diode) 102a faces each of the openings. And a light receiving element (photodiode) 102b.

  In the punch unit 60 having the above-described configuration, in the present embodiment, a static elimination member 160 made of a conductive member that neutralizes static electricity charged in the punch scraps 130 generated by the punching process is disposed in the movable region of the punch punch 64. Yes.

  12 and 13 show the configuration of the charge removal member 160.

  This static elimination member 160 is provided with a ring-shaped main body 162 having a circular opening 161 at the center, and a predetermined length extending from the main body 162 toward the center of the opening 161 at a predetermined interval. A plurality of static elimination needles 163 are included. And the main-body part 162 of the static elimination member 160 is being fixed to the lower surface side of the lower paper guide 62b in the state which made the opening part 161 correspond to the through-holes 62a1 and 62b1 of both paper guides 62a and 62b. The main body 162 is grounded via a device frame (not shown).

  Thus, during punching, the punch punch 64 passes down the opening 161 while pushing down the punch scraps 130 after punching, whereby the tip of the static elimination needle 163 is pushed and bent downward (FIG. 12B). As a result, the static elimination needle 163 is in contact with the punch waste 130 and the punch punch 64 (more precisely, the static elimination needle 163 is in contact with the side surface of the punch waste 130 and the side surface of the punch punch 64). It has become. That is, when the punch punch 64 is lowered, both the punch waste 130 punched out by the punch punch 64 and the punch punch 64 come into contact with the static elimination needle 163 in turn, and not only the punch waste 130 but also the punch punch. In 64, the charged static electricity is removed.

  Thereby, since the punch waste 130 punched out from the paper P is surely discharged, the punch waste 130 is not adsorbed to the die auxiliary guide plate 68 or the wall surface of the storage container 63 disposed below, so that the inside of the storage container 63 Can be dropped naturally. Further, since the punch punch 64 is also neutralized, when the punch punch 64 after punching rises through the punch hole P1 of the paper P, the paper P is moved to the punch punch 64 side by the influence of static electricity. It will not be pulled. Thereby, it is possible to prevent the punch hole P1 of the paper P from being deformed due to the punch punch 64 being pulled out.

  Further, in the present invention, since the static elimination needle 163 of the static elimination member 160 is provided so as to project within the movable region of the punch punch 64, the protruding length of the static elimination needle 163 becomes a problem.

  In other words, if the protruding length is long, the tip of the static elimination needle 163 wound around the tip of the punch punch 64 when the punch punch 64 is lowered causes the punch punch 64 and the die auxiliary guide plate 68 (Claim 6). (Corresponding to the punching die described)), the static elimination needle 163 may be damaged and the punch unit 60 may malfunction. Therefore, the protruding length of the static elimination needle 163 is such that the tip of the static elimination needle 163 does not enter the space when the punching punch 64 descends to the lowest end and enters the die auxiliary guide plate 68. It is good to do.

  Similarly, if the discharge needle 163 has a long protruding length, the tip of the charge removal needle 163 wound around the tip of the punch punch 64 when the punch punch 64 is raised is the upper surface side of the lower paper guide 62b, that is, the sheet. There is a possibility that the charge removal needle 163 will be damaged, the punch hole of the paper will be damaged, and the punch unit 60 will malfunction. For this reason, the protruding length of the static elimination needle 163 is preferably set to a length that does not enter the upper surface side of the lower paper guide 62b, that is, the paper conveyance path.

  Further, as a problem in the case where the protruding length of the static elimination needle 163 is long, it is conceivable that when the punch punch 64 is raised, the static elimination needle 163 is caught in the elevation and is bent upward.

  Therefore, in the present invention, as shown in FIG. 14A, the static elimination needle 163 is provided in a curved shape so that the tip portion hangs downward. Or as shown in FIG.14 (b), the static elimination needle 163 is inclined and provided in the downward direction. By providing the static elimination needle 163 in this manner, even if the length of the static elimination needle 163 is somewhat long, the contact operation between the static elimination needle 163 and the punch punch 64 becomes smooth, and the static elimination needle 163 is brought into contact with the punch punch 64 by the contact pressure. Inconveniences such as being caught in the rise and bending upward are not generated. Further, by providing the static elimination needle 163 in this way, the contact distance (that is, the contact time) between the punch scraps 130 and the punch 64 for punching can be increased, so that the static elimination effect can be reliably obtained. .

  In the present embodiment, as described above, the punching die 65 and the punching punch 64 are aligned based on the detected value in the paper width direction of the line sensor 36f. The shape of 162 needs to be a shape that takes into account the movement due to the alignment of the punch punch 64. For example, in the above example, the opening 162 has a circular shape, but may have an elliptical shape that is slightly longer in the paper width direction.

  In addition to this, for example, the static elimination member 160 may be configured to be movable in accordance with the alignment of the punch die 65 and the punch punch 64. As an example, when the die auxiliary guide plate 68 opposed to the punching die 65 and the punching punch 64 has a mechanism structure that moves integrally with the punching die 65 and the punching punch 64, this die is used. The main body 161 of the static elimination member 160 may be fixedly disposed at the upper end of the auxiliary guide plate 68.

1 is a diagram illustrating a schematic configuration of a multifunction machine to which the present invention is applied. FIG. 4 is an explanatory diagram illustrating a schematic configuration of a paper post-processing unit and a paper discharge tray. FIG. 4 is a perspective view showing a paper post-processing section and a paper discharge tray, and shows a state in which the paper discharge tray is contracted and raised, and a state in which a cover is closed. FIG. 6 is a perspective view illustrating a state where a paper discharge tray is lowered. FIG. 6 is a perspective view illustrating a state where a paper discharge tray is extended. It is a perspective view which shows the state which the cover opened. FIG. 6 is a perspective view illustrating a state where a paper discharge tray and a staple unit are slid. It is explanatory drawing which shows engagement with the hook of a staple unit, and the engaging groove of a punching unit. It is explanatory drawing which shows contact | abutting with the protrusion for a regulation of a cover, and the groove part for a regulation of a staple unit. It is a partial expansion schematic sectional drawing which shows the more detailed structure of a punch unit. (A)-(d) is explanatory drawing which shows the punch operation | movement by the punch for punches. It is explanatory drawing which shows the structure of a static elimination member. It is a perspective view which shows the structure of a static elimination member. (A), (b) is explanatory drawing which shows the other arrangement | positioning shape of a static elimination needle. It is explanatory drawing which shows the accommodation state of the punch waste of the punch waste storage container by the conventional punch processing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Multifunction device 2 Scanner part 3 Image forming part 5 Paper post-processing part 8 Paper discharge tray 31 Image forming system 33 Paper cassette 36e Paper discharge roller 36f Line sensor 36f1 Light emitting element (light emitting diode)
36f2 light receiving element (photodiode)
50 Cover 50c Restriction protrusion 51 Main transport path 52 Switchback transport path 53 Branch claw 54 Discharge roller 55 Switchback roller 60 Punch unit 61 Punch hole punching mechanism 62 Paper guide 62a Upper paper guide 62b Lower paper guide 62a1, 62b1 Through hole 63 Punch waste storage container (storage container)
64 Punch punch 65 Die for punch 66 Engagement groove 67 Rotary cam (Eccentric cam)
67a Punch shaft 68 Dice auxiliary guide plate 70 Staple unit 70c Restricting groove 71 Staple mechanism portion 72 Staple table 74 Paper discharge roller 75 Slide member 76 Hook 81 First paper discharge tray 82 Second paper discharge tray 83 Third paper discharge tray 91 , 92 Shield member 102 Full detection sensor 102a Light emitting element (light emitting diode)
102b Light receiving element (photodiode)
130 Punch waste 160 Static elimination member 161 Opening portion 162 Main body portion 163 Static elimination needle

Claims (8)

In a punch processing apparatus that is disposed in the middle of a transport process for transporting printed paper to a stacking position of a discharge unit and performs punch processing on a transport paper using a punch for punching,
A punch processing apparatus, wherein a static eliminating member for neutralizing static electricity charged in punch scrap generated by the punching process is disposed in a movable region of the punch for punching.   The static eliminating member is composed of a main body having an opening and a number of static eliminating needles extending from the main body toward the central portion of the opening. During punching, the punch punch is punched. 2. The punch processing apparatus according to claim 1, wherein the punch scraps, the punch for punching, and the static elimination needle are in contact with each other by passing through the opening while pushing subsequent punch scraps. The punch for punch performs a punching process by passing through a through hole formed in a paper guide constituting a paper conveyance path from above and descending,
3. The punch processing apparatus according to claim 2, wherein a main body portion of the static elimination member is fixed to a lower surface side of the paper guide in a state where the through hole and the opening portion are aligned.   The punch processing apparatus according to claim 3, wherein the static elimination needle is provided in a curved shape so that a tip portion thereof hangs downward.   The punch processing apparatus according to claim 3, wherein the static elimination needle is provided to be inclined downward.   3. The neutralization needle according to claim 2, wherein the neutralization needle has a length at least such that the leading end of the neutralization needle is movable and does not enter a space formed by the punch for punch and the punch die. 6. The punch processing apparatus according to any one of 5 above.   6. The neutralization needle according to any one of claims 2 to 5, wherein the neutralization needle has a length at least so that the punching punch is movable and a leading end portion of the neutralization needle does not enter the paper conveyance surface of the paper conveyance paper guide. The punch processing apparatus according to 1.   The punch processing apparatus according to claim 1, wherein the static eliminating member is grounded via an apparatus frame.

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