JP4921182B2 - Discharge stacking apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a paper discharge stacking device for stacking discharged sheets, printing paper, transfer materials, recording materials and the like (hereinafter referred to as “paper”), a printing apparatus including a stencil printing device provided with the same, and an ink jet The present invention relates to an image forming apparatus having functions such as a recording apparatus, a copying machine, a printer, a facsimile machine, or a plotter, or an image forming apparatus such as a multifunction machine having a plurality of functions.

There is known a paper discharge stacking device that is connected to a stencil printing apparatus, which is an example of an image forming apparatus, and stacks printed paper (hereinafter also referred to as “paper discharge”) that is a paper on which an image has been formed. The paper discharge stacking device is provided with a paper discharge base for sequentially stacking image-formed paper discharged in the paper discharge direction, and can be moved and stopped in the paper discharge direction on the paper discharge base, that is, the position can be adjusted and discharged. An end fence that accepts the printed paper and aligns the paper discharge direction of the paper, and can be adjusted in the paper width direction perpendicular to the paper discharge direction in the paper discharge stand, and provided opposite to each other, A pair of side fences that align the paper in the paper width direction are provided (see, for example, Patent Documents 1 and 2). The end fence has a paper collision surface made of an impact absorbing member for absorbing the impact energy when the leading edge of the paper collides to reduce the impact.
In the conventional paper discharge stacking apparatus, first, printing is performed by setting the positions of the end fence and the side fence according to the paper size.

JP-A-9-208108 Japanese Patent Laid-Open No. 10-59608

However, the types of paper used in the stencil printing apparatus are, for example, from thin paper such as printed paper and reprint paper to standard paper such as stencil fine paper and plain paper, such as thick paper such as drawing paper and postcards. Various materials having different waist strength are used, and they are generally printed in large quantities such as several hundred sheets or more. Printed paper that is ejected from the paper ejection suction and transport unit on the stencil printing machine side collides with the paper collision surface of the end fence and falls, but the strength of the waist depends on the ratio of the printed image area and the printing speed. Therefore, the shock absorption member alone of the end fence cannot absorb the shock, and unexpected rebounding occurs, and the paper position is shifted from the normal output alignment position on the output tray. As a result of the loading, the output alignment was getting worse.
Thus, conventionally, when the paper discharge alignment is poor, the next paper is also stacked on the paper discharge stand in a state where the paper alignment is poor. “User”) had to make corrections for the output of all the stacked sheets. Further, as described above, there is a possibility that the discharge alignment may deteriorate during printing, so that there is a problem that the operator must always stand by during printing.

  Therefore, the present invention has been made in view of the above-described circumstances, and detects the loaded / stacked state of the paper after being bounced off by the end fence in the vicinity of the rear end position of the paper stacked on the paper discharge tray. By detecting the position of the trailing edge of the paper, a warning is given, and when there is a sorting device, the trailing edge position of the paper is automatically corrected using this, If there is an angle adjustment mechanism, use this to reset the angle of the end fence, or stop printing if the amount of misalignment of the trailing edge of the paper is large. The main purpose is to prevent deterioration.

In order to solve the above-described problems and achieve the above-described object, the invention according to each claim employs the following characteristic means and configuration.
According to the first aspect of the present invention, there is provided a paper discharge tray on which image-formed sheets discharged in the paper discharge direction are sequentially stacked, and an end fence that can be adjusted in position in the paper discharge direction on the paper discharge base; In a paper discharge stacking device comprising a pair of side fences that can be adjusted in the paper width direction perpendicular to the paper discharge direction in the paper discharge table and are opposed to each other, on the paper discharge table There are a plurality of rear end position detecting means for detecting the rear end position of the stacked paper, and at least two of the plurality of rear end position detecting means are placed on the discharge table in a regular discharge aligned state. It is characterized in that it is arranged on the paper discharge stand in the vicinity of the rear end position of the sheet exposed from the rear end of the stacked sheets .

According to a second aspect of the invention, the sheet discharge stacking apparatus according to claim 1, at least two of the plurality of trailing edge position detecting means, be in the paper width of the minimum size of paper to be used, In addition, they are arranged on substantially the same straight line in the paper width direction.

According to a third aspect of the invention, the sheet discharge stacking apparatus according to claim 2, comprising a notifying means for notifying the information, there when the trailing edge of the sheet is detected by said at least two rear position detecting means Thus, the notification means is used to make different notifications when detected by only one of the at least two rear end position detection means and when detected by two.

According to a fourth aspect of the present invention, in the paper discharge stacking apparatus according to any one of the first to third aspects, the apparatus includes an angle adjusting unit capable of adjusting an angle of the end fence with respect to the paper carry-out direction, When the trailing edge of the sheet is detected by at least one of the two trailing edge position detecting means, the angle adjusting means is used to adjust the angle of the end fence.

According to a fifth aspect of the present invention, in the paper discharge stacking apparatus according to any one of the first to fourth aspects, the paper stacked on the paper discharge table is shifted in the direction opposite to the paper carry-out direction for sorting. Having a sorting means, and when the trailing edge of the sheet is detected by at least one of the at least two trailing edge position detecting means, the sorting means is used to detect a sheet shifted in a direction opposite to the sheet carrying-out direction. It is characterized by making corrections.

According to a sixth aspect of the present invention, in the paper discharge stacking apparatus according to any one of the first to fifth aspects, at least one of the plurality of rear end position detecting means is set to be closer than the vicinity of the rear end position. Further, it is arranged at a position near the rear end.

According to a seventh aspect, an image forming unit for forming an image on a sheet, an image forming apparatus having a sheet image formed and a discharge means for discharging to the discharge tray on, according to claim 6, wherein the paper discharge An image forming operation is stopped when the trailing edge of the sheet is detected by the trailing edge position detecting means that has a stacking device and is disposed at a position near the trailing edge.

Invention according to claim 8, an image forming unit for forming an image on a sheet, the sheet of imaged image forming apparatus and a discharging means for discharging to the discharge tray on any of claims 1 to 6 It is characterized by having the discharge stacking apparatus described in any one of the above.

According to the present invention, it is possible to realize and provide a novel paper discharge stacking apparatus and an image forming apparatus having the same by solving the above problems. The main effects of the invention are as follows.
According to the first and second aspects of the present invention, when the sheet on which the image has been formed collides with the end fence during the image forming operation, the rebound of the sheet is large and the sheets are aligned on the sheet discharge table. There when deteriorated, it is possible to accurately detect the state aligned its discharged in easy single structure, it is possible to suppress the deterioration of alignment and thus the sheet discharge.

According to the third aspect of the present invention, when the discharge alignment on the discharge tray is deteriorated, it is possible to appropriately notify the user of the discharge alignment state corresponding to the deteriorated state.

According to the fourth aspect of the present invention, in the paper stacking apparatus having the angle adjusting means capable of adjusting the angle of the end fence with respect to the paper carry-out direction, at least one of the at least two rear end position detecting means is used. When the trailing edge of the paper is detected, the angle of the end fence is automatically adjusted, so that it is possible to correct the paper discharge alignment state that is getting worse, and to suppress the deterioration of paper discharge alignment. it can.

According to the fifth aspect of the present invention, at least two rear end position detections are provided in the sheet stacking apparatus having the sorting unit that performs sorting by shifting the sheets stacked on the sheet discharge table in the direction opposite to the sheet carrying-out direction. When the trailing edge of the paper is detected by at least one of the means, it is possible to correct the paper shifted in the direction opposite to the paper carry-out direction using the sorting means, and suppress the deterioration of the paper discharge alignment. be able to.

According to the sixth aspect of the present invention, at least one of the plurality of rear end position detecting means is arranged at a position closer to the rear end than the vicinity of the rear end position, so that an image is formed during the image forming operation. When an already-fed paper collides with the end fence, it detects a paper discharge alignment state where the paper bounces back further and the paper output alignment on the paper output tray is greatly shifted to a level that requires artificial correction. As a result, it is possible to stop the image forming operation by the image forming apparatus on which the paper discharge stacking device is mounted, thereby suppressing the deterioration of the paper discharge alignment and preventing waste of paper in advance. It becomes possible.

According to the seventh aspect of the present invention, when the sheet on which the image has been formed collides with the end fence during the image forming operation, the rebound of the sheet is further increased, and the sheet is aligned on the sheet discharge table. By detecting a paper discharge alignment state that has deteriorated by a large shift to a level that requires artificial correction, the image forming operation is stopped, thereby suppressing deterioration of the paper discharge alignment and preventing waste of paper in advance. An image forming apparatus capable of realizing the above can be realized and provided.

According to the invention described in claim 8, it is possible to realize and provide an image forming apparatus having the effect of the invention described in any one of claims 1 to 5 .

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention including examples will be described with reference to the drawings. In each embodiment and the like, components (members and components) having the same function, shape, and the like will be omitted by giving the same reference numerals after being described once. In the figure, components that are configured in a pair and do not need to be specifically distinguished and described are described by appropriately describing one of them for the sake of simplification of description. In order to simplify the drawings and the description, even if the components are to be represented in the drawings, the components that do not need to be specifically described in the drawings may be omitted as appropriate. When quoting and explaining constituent elements such as published patent gazettes, the reference numerals are shown in parentheses to distinguish them from those of the embodiments.

(First embodiment)
1 to 6 show a first embodiment of the present invention. First, referring to FIG. 1, the overall operation of the digital thermosensitive stencil printing apparatus 1 as an example of the image forming apparatus according to the present invention will be briefly described and its overall operation will be briefly described. The configuration and operation of a typical paper discharge stacking device will be described in detail.
In FIG. 1, reference numeral 8 denotes an apparatus main body including a frame or the like that forms the framework of the stencil printing apparatus 1. As shown in the figure, the portion indicated by reference numeral 2 in the approximate center of the apparatus main body 8 is a printing section having a printing drum 101 or the like having a porous cylindrical plate cylinder on the outer periphery, and the right side of the printing drum 101. The part indicated by reference numeral 3 is the plate making part, the part indicated by reference numeral 4 below the plate making part 3 is the paper feeding part, the part indicated by reference numeral 5 on the left side of the printing drum 101 is the discharging part 5, and the left side of the printing part 2 The portion indicated by reference numeral 6 below the plate discharging unit 5 indicates the paper discharge unit, and the portion indicated by reference numeral 7 above the plate making unit 3 and the plate discharging unit 5 indicates the image reading unit. Hereinafter, in this specification, the “plate cylinder” is referred to as a printing drum.

  The printing unit 2 supplies ink to the plate-making master 61 on the printing drum 101 having a function of winding the plate-making master 61 around its outer peripheral surface, and feeds it to the printing drum 101 by pressing means described later. The plate making unit 3 has a function of directly pressing a sheet P as an example of a sheet-like recording medium fed from the unit 4 to form a print image on the sheet P. The plate making unit 3 has a master 61 wound in a roll shape. The function of making the plate and feeding the plate, the paper feed unit 4 uses the function of feeding the paper P stacked on the paper feed tray 51 to the printing unit 2, and the plate discharge unit 5 uses the outer peripheral surface of the printing drum 101. The paper discharge unit 6 transports and discharges the printed paper P printed by the printing unit 2 to the paper discharge tray 11 with a function of peeling off the master 61 and discharging and discharging the master 61 into the plate discharge box 74. The function of the image reading unit 7 is not shown in FIG. A function of reading an image of the surface of the document 60 to be transferred from each have.

Next, the basic operation of the stencil printing apparatus 1 will be described while supplementing its configuration. The operation of the stencil printing apparatus 1 is performed under the control of the control means 55 shown in FIG.
First, the user sets a document 60 having an image to be printed on a document placing table (not shown) arranged at the top of the image reading unit 7, and presses the plate making start key 41 of the operation panel 40 shown in FIG. In response to pressing of the plate making start key 41, a plate making start signal is generated, and this is used as a trigger to first execute a plate discharging process. That is, in this state, the used master 61 used in the previous printing remains attached to the outer peripheral surface of the printing drum 101. The printing drum 101 is rotatably supported around the support shaft 104. The printing drum 101 is connected to a main motor 151 as a printing drum driving unit via a driving mechanism (not shown), and is rotated by the main motor 151.

  The printing drum 101 rotates in the direction opposite to the direction of arrow A in the figure, and the rear end portion of the used master 61 mounted on the outer peripheral surface of the printing drum 101 is connected to the pair of discharge plate peeling rollers 71a and 71b of the discharge plate portion 5. When approaching, the roller pair 71a, 71b rotates while scooping up the rear end portion of the used master 61 by one of the plate release roller 71b, and a plate discharge roller pair disposed to the left of the plate release roller pair 71a, 71b. The used master 61 is gradually moved from the outer peripheral surface of the printing drum 101 by a plate release peeling / conveying device comprising a pair of discharging plate conveying belts 72a and 72b stretched between 73a and 73b and a pair of discharging plate peeling rollers 71a and 71b. While being peeled and conveyed in the direction of the arrow Y1, the sheet is discharged into the discharge box 74, and so-called discharge is completed. At this time, the printing drum 101 continues to rotate counterclockwise. The discharged used master 61 is then compressed inside the discharging plate box 74 by the compression plate 75.

In parallel with the plate removal process, the image reading unit 7 operates to read the original. That is, the document 60 placed on the document table is conveyed in the directions of the arrows Y2 to Y3 by the rotation of the separation roller 81, the front document transport roller pair 82a and 82b, and the rear document transport roller pair 83a and 83b. It is used for exposure reading. At this time, when there are a large number of documents 60, only the lowermost document is conveyed by the action of the separating blade 84.
The upper rear document transport roller 83a is rotationally driven by a document transport stepping motor (not shown). The upper front document transport roller 82a is rotationally driven by the document transport stepping motor via a timing belt (not shown) spanned between the upper transport roller 83a and the transport roller 82a, and each roller 82b. , 83b are driven to rotate.

When reading the image of the original 60, the reflected light from the surface of the original 60 illuminated by the fluorescent lamp 86 while being transported on the contact glass 85 is reflected by the mirror 87 and passes through the lens 88, and then the CCD (photocoupler such as a charge coupled device) is read. This is performed by being incident on an image sensor 89 formed of a conversion element. The document 60 from which the image has been read is discharged onto the document tray 80A.
The optical information of the document 60 is photoelectrically converted by the image sensor 89, and the analog electric signal is input to an analog / digital (A / D) converter (not shown) and converted into a digital image signal. This digital image signal is subjected to image processing by an image processing device (not shown), and the image signal thus subjected to image processing is input to a plate making control unit (not shown), and a signal for driving a thermal head is obtained. It is generated and transmitted to a thermal head drive circuit (not shown).

  On the other hand, in parallel with such document scanning and image reading operations, plate making and plate feeding processes are performed based on image information converted into digital signals. That is, when the master-making stepping motor (not shown) is driven to rotate by the plate-making start signal as a trigger, the master 61 is set so that it can be fed out via a master support member (not shown), and rolled around the core tube 61a. The master 61 is pulled out from the master roll 61b formed by being wound into a shape. The pulled-out master 61 is sub-scanning that is also in the master conveyance direction indicated by an arrow Y in the figure by rotation at a constant speed of the platen roller 92 and the feed roller pair 93a, 93b pressed against the thermal head 91 via the master 61. It is conveyed downstream in the direction Y. A large number of minute heating elements 91a arranged in a line in the main scanning direction of the thermal head 91 with respect to the conveyed master 61 correspond to digital image data signals sent from the plate making control unit. Then, each of the thermoplastic resin film portions of the master 61 in contact with the heat generating element 91a that selectively generates heat is heated, melted and perforated. In this way, the image information is written in the master 61 as a drilling pattern by position-selective melt drilling of the master 61 according to the image information.

The front end of the master 61 having image information written therein is fed toward the outer peripheral side of the printing drum 101 by a pair of feed rollers 94a and 94b, and the traveling direction is changed downward by a plate feed guide plate (not shown). 1 hangs down toward the master clamper 102 in which the printing drum 101 is stopped at the plate feeding position indicated by a two-dot chain line in FIG. At this time, the used master 61 has already been removed from the printing drum 101 by the plate discharging process.
When the leading end of the master 61 that has been subjected to plate making is clamped and held by the master clamper 102 at a certain timing by the operation of an opening / closing device (not shown) disposed on the apparatus body 8 side to open and close the master clamper 102, the printing drum 101 Is gradually wound around the outer peripheral surface of the master 61 while rotating in the arrow A direction (clockwise direction). After the plate making is completed, the rear end portion of the master 61 that has been subjected to plate making is cut into a fixed length by the cutter 95, and the master 61 that has been made one plate is completely wound around the outer peripheral surface of the printing drum 101. The plate making and feeding processes are completed.

  Thereafter, the rotation of the platen roller 92, the feed roller pair 93a, 93b, and the plate feed roller pair 94a, 94b causes the tip of the remaining upstream master 61 to be cut toward the nip portion of the plate feed roller pair 94a, 94b. Be transported. When the leading edge of the master 61 thus conveyed is detected by a master leading edge detection sensor (not shown) and it is determined that the leading edge of the master 61 has occupied the initial position, the platen roller 92, the feed roller pair 93a, 93b, and the plate feeding roller pair 94a. , 94b is stopped, and a plate-making standby state is prepared for the next plate-making. The initial position of the master 61 is set in advance, for example, to a position slightly protruding forward from the position sandwiched between the nip portions of the plate feed roller pair 94a, 94b.

  Next, the printing process is started. First, the uppermost one of the sheets P stacked on the sheet feeding table 51 is moved in the direction indicated by the arrow Y4 (hereinafter referred to as “the registration roller pair 113a, 113b” by the sheet feeding roller 111 and the separation roller pair 112a, 112b). And is fed between the printing drum 101 and the press roller 103 in the printing unit 2 at a predetermined timing synchronized with the rotation of the printing drum 101 by the registration roller pair 113a and 113b. Is done. The press roller 103 is brought into and out of contact with the outer peripheral surface of the printing drum 101 by a press roller displacing means (not shown), and is fed to the printing drum 101 on which the master 61 having been made on the outer peripheral surface is wound. It has a function as a pressing unit that presses the received paper P to form a printed image on the paper P. When the fed paper P is inserted between the printing drum 101 and the press roller 103, the press roller 103 that has been separated below the outer peripheral surface of the printing drum 101 is swung and raised. As a result, it is pressed against the master 61 that has been pre-rolled around the outer peripheral surface of the printing drum 101. In this way, due to the adhesive force due to the viscosity of the ink that has oozed out from the porous portion of the printing drum 101, the master 61 that has been subjected to plate making comes into close contact with the outer peripheral surface of the printing drum 101, and at the same Ooze out and the oozed ink is transferred to the surface of the paper P to form a printed image.

  At this time, on the inner peripheral side of the printing drum 101, ink is supplied from an ink supply distributor (not shown) to an ink reservoir 122 formed between the ink roller 120 and the doctor roller 121, and the same direction as the rotation direction of the printing drum 101. Ink is supplied to the inner peripheral side of the printing drum 101 by the ink roller 120 that is in contact with the inner peripheral surface while rotating in synchronization with the rotation speed of the printing drum 101.

  The printed paper P on which the print image is formed in the printing unit 2 is peeled off from the print drum 101 by the paper discharge peeling claw 62 in the paper discharge unit 6 and sucked by the negative pressure generated by the operation of the suction fan 67. As a result of the counter-clockwise rotation of the conveying belt 66, which is an endless belt stretched over the paper discharge inlet roller 64 and the suction paper discharge roller 65, the discharge direction of the printed paper P indicated by the arrow Y5 (hereinafter referred to as "paper"). In the discharge direction Y <b> 5 ”) and discharged onto the paper discharge tray 11.

At this time, the printed paper P is curved and deformed in a substantially U shape by a jumping table 68 as a waisting means disposed on the downstream side of the conveying belt 66, so that the apparent waist strength can be increased. The front end of the center of the printed paper P collides with a paper collision surface formed by an impact absorbing member (not shown) provided on an end fence 12 provided upright on the paper discharge table 11. At this time, most of the impact energy applied to the printed paper P is absorbed by the impact absorbing member, so that the rebound from the paper collision surface of the end fence 12 is reduced, so that the printed paper is printed. Alignment / discharge alignment in the P sheet discharge direction Y5 is performed.
The printed paper P is aligned in the height direction of the end fence 12 while the both ends of the printed paper P are aligned by the pair of side fences 13a and 13b disposed on the left and right sides of the paper discharge direction Y5. The sheets are discharged and stacked in an orderly manner on the discharge stacking surface 11a of the discharge table 11 positioned below Z.

  In this way, the plate printing is completed. The printing speed at the time of plate printing (referred to as printing for bringing the master 61 on the outer peripheral surface of the printing drum 101 into close contact with the adhesive force of the oozing ink) is set to a low speed. After the plate printing is completed, the press roller 103 is separated from the printing drum 101, and the printing drum 101 returns to the initial position where the master clamper 102 is substantially above in FIG.

  Next, by pressing the printing speed setting key 44 of the operation panel 40 shown in FIG. 2, a desired printing speed value (any one of printing speed levels 1 to 5, for example, 60 rpm (sheets / minute) to Is set in increments of 15 rpm up to 120 rpm), and before and after this, the number of prints is set with the numeric keypad 43 shown in the figure, and when the print start key 42 shown in the figure is pressed, In the same process, the paper feeding, printing, and paper ejection processes are repeated for the set number of prints at the set printing speed, and all the processes of stencil printing are completed.

The configuration of the operation panel 40 will be supplemented. In FIG. 1, an operation panel 40 for operating the stencil printing apparatus 1 is disposed above the image reading unit 7 in the stencil printing apparatus 1. The operation panel 40 has a plate making start key 41 for setting and inputting activation of each operation from image reading of a document image to plate printing, and printing for activating printing operation for the number of prints set / input by the ten key 43. A start key 42 and a numeric keypad 43 for setting / inputting the number of prints and the like are arranged.
Also, the operation panel 40 is set with a print speed setting key 44 for selectively setting one print speed from among five print speeds of, for example, print speed levels 1 to 5 and a print speed setting key 44. A speed indicator 45 composed of an LED (light emitting diode) lamp group for displaying a set printing speed, a 7-segment display section 49A for displaying the number of printed sheets set / input by pressing the numeric keypad 43, and various types described later. A warning display, an operation sequence of the stencil printing apparatus 1, a liquid crystal display unit 49 </ b> B for displaying a letter indicating that the master 61 or the paper P has jammed, or displaying a picture of the occurrence location are arranged.
Here, the liquid crystal display unit 49B functions as an informing means for warning / notifying information. The notification means is not limited to the liquid crystal display unit 49B that displays a warning by character display or picture display, but may be a warning display by LED lighting / blinking display, a warning display by buzzer sounding, or an appropriate combination thereof. May be.

  Next, the detailed configuration of the paper discharge unit 6 will be described with reference to FIGS. The paper discharge unit 6 is provided so as to be close to the outer peripheral surface of the print drum 101 and the paper discharge table 11 on which the printed paper P on which the print image discharged in the paper discharge direction Y5 is transferred is sequentially stacked. A sheet discharge claw 62 that separates the printed sheet P from the upper master 61, and a printed sheet P that has been separated by the sheet discharge claw 62 is sucked and conveyed in the sheet discharge direction Y5. The paper discharge suction conveyance unit 63 discharged onto the paper table 11 and the printed paper P disposed on the downstream side of the paper discharge suction conveyance unit 63 are curved and deformed in a substantially U-shape. A pair of jumping tables 68 as a means for increasing the waist strength of the sheet and a printed sheet P discharged and provided so as to be able to move and stop in the sheet discharging direction Y5 on the sheet discharging table 11, that is, to be position-adjustable. Take it The end fence 12 that aligns the paper discharge in the paper discharge direction Y5 on the paper P, and the paper width direction X that is orthogonal to the paper discharge direction Y5 on the paper discharge tray 11 can be adjusted in position and face each other, printing A pair of side fences 13a and 13b that perform discharge alignment in the paper width direction X on the finished paper P are provided.

The paper discharge suction conveyance unit 63 mainly includes the suction fan 67, the suction paper discharge inlet roller 64, the suction paper discharge outlet roller 65, and the conveyance belt 66. The suction discharge roller 65 is connected to a drive motor (not shown) via a drive force transmission means (not shown) and is driven to rotate by the drive motor.
The discharge conveyance speed of the conveyance belt 66 by the drive motor is substantially equal to the discharge speed of the printed paper to the discharge tray 11 and can be appropriately changed according to the printing speed of the printing drum 101.
A plurality of conveying belts 66 are stretched between the suction discharge outlet roller 64 and the suction discharge outlet roller 65 separately in the paper width direction. A paper discharge sensor 69 serving as an image forming number counting means for counting the number of printed sheets P is disposed between the adjacent conveyance belts 66 and on the stationary member of the paper discharge suction conveyance unit 63. The paper discharge sensor 69 is composed of, for example, a reflective photosensor.

The paper discharge tray 11 has a shallow housing shape and is assembled by a housing-shaped paper discharge base member having a paper discharge stacking surface 11a and a lid member that covers the bottom of the paper discharge tray base member. The discharge table base member and the lid-like member of the discharge table 11 are made of resin such as ABS resin (ABS), polystyrene (PS), polycarbonate resin (PC), etc., and contribute to weight reduction and low cost. Yes.
As shown in FIGS. 1 and 3, a pair of side fences 13 a and 13 b and an end fence 12 are respectively provided on a discharge base member (hereinafter simply referred to as “discharge tray 11”) of the discharge tray 11. It is provided upright. The base fences of the side fences 13a and 13b are supported by a stay member (not shown) provided on the paper discharge table 11. Although not shown, the side fences 13a and 13b move on the paper discharge table 11 according to the paper size in the paper discharge width direction. Are respectively slidable and movable, and foldable toward the inside on which printed paper P is stacked. Further, the side fences 13a and 13b are connected by a well-known rack and pinion mechanism. When one of the side fences 13a and 13b is moved, the other side fence 13a and 13b are also moved in association with each other by the same amount.

  The end fence 12 is erected on the paper discharge tray 11 and is laid on a rail member (not shown) fixed so as to be flush with the paper discharge tray 11 in a direction parallel to the paper discharge direction Y5. It is attached slidably and freely to fit. The end fence 12 and the side fences 13a and 13b are integrally formed of a resin such as ABS resin (ABS), polystyrene (PS), polycarbonate resin (PC), for example, and contribute to weight reduction and low cost. Yes.

  In FIG. 1 and FIG. 3, the code | symbol 10 shows the paper discharge stacking apparatus of this embodiment. The paper discharge stacking apparatus 10 is mainly composed of the paper discharge tray 11, the end fence 12, a pair of side fences 13a, 13b, and stacked paper rear end detection sensors 4a, 4b, 4c, which will be described in detail later. Has been. The paper discharge stacking apparatus 10 of the present embodiment will be described by taking a manual paper discharge stand as an example, but can be applied to a paper discharge stacking apparatus having a known automatic paper discharge stand.

  The paper discharge stacking surface 11a of the paper discharge tray 11 is arranged so that the end fence 12 and the side fences 13a and 13b can be moved to a fixed position even if the size of the paper stacked on the paper discharge stacking surface 11a is different. The paper size to be loaded is displayed. In the known automatic paper discharge tray, the end fence 12 and the side fences 13a and 13b are automatically moved to the same paper size position as the manual paper discharge tray according to the paper size information.

  A plurality (three in this embodiment) of detecting the rear end position of printed paper P (hereinafter also referred to as “stacked paper PA”) discharged and stacked on the paper discharge stacking surface 11 a is provided on the paper discharge tray 11. ) As the trailing edge position detecting means, respectively, are disposed at predetermined positions, which will be described later, of the paper discharge tray 11. The stacked paper trailing edge detection sensors 14a, 14b, and 14c are each composed of a reflective photosensor. 3, 5, 6, and the like, a portion shown in a round shape indicates an opening formed of glass or a transparent resin that transmits light emitted from the reflective photosensor and reflected light.

FIG. 3 also shows a state in which stacked paper PAs of four types of paper sizes A3, B4, A4, and B5 are discharged and stacked on the paper discharge tray 11 in a regular paper discharge alignment state. Hereinafter, for convenience of description, it is assumed that the minimum size paper used in the stencil printing apparatus 1 of the present embodiment is up to B5 side (showing the paper size when viewed from the paper width direction X).
Of the stacked paper trailing edge detection sensors 14a, 14b, and 14c, the two stacked paper trailing edge detection sensors 14a and 14b are the trailing edges of the stacked paper PA discharged and stacked on the paper discharge tray 11 in a regular paper discharge alignment state. Is located in the vicinity of the rear end position of the stacked paper PA exposed from the sheet, in other words, not positioned under the stacked paper PA, and is disposed in the vicinity of the rear end position of the stacked paper PA that is not covered and hidden by the stacked paper PA. They are arranged within the paper width dimension next to the minimum size paper B5 used in the printing apparatus 1 and on the same straight line in the paper width direction X of the paper discharge tray 11.
As shown in FIG. 3, when the stacked paper PA of paper sizes A3, B4, A4, and B5 is discharged and stacked on the paper discharge tray 11 in a regular paper discharge alignment state, the stacked paper trailing edge detection sensor 14a, Both 14b and 14c are in an off / detection (hereinafter also referred to as “off”) state.
The stacked paper trailing edge detection sensors 14a and 14b are arranged at a position away from the trailing edge of the stacked paper PA discharged and stacked on the paper discharge tray 11 in the regular paper discharge alignment state on the upstream side in the paper discharge direction Y5. Whether or not to do so is set appropriately through experiments.

  The loaded sheet trailing edge detection sensor 14c is positioned closer to the trailing edge of the sheet discharge tray 11 than the two stacked sheet trailing edge detection sensors 14a and 14b (the position of the sheet discharge tray 11 more than the stacked sheet trailing edge detection sensors 14a and 14b). (Position upstream of the paper discharge direction Y5) and at the center of the paper width direction X of the paper size used in the stencil printing apparatus 1.

With reference to FIG. 4, the control configuration of the main part of the stencil printing apparatus 1 will be described.
In the figure, the control means 55 is provided inside the apparatus main body 8 and comprises a microcomputer having a CPU 56, a ROM 57, a RAM 58, a timer and the like. Various operation signals (on / off signals and data signals related to activation and setting) are input to the control means 55 from the operation panel 40. Further, a signal from a home position sensor (not shown) for detecting the initial position (home position) of the printing drum 101 is sent to the control means 55 from the stacked paper trailing edge detection sensors 14a, 14b, and 14c in the paper discharge stacking device 10. An on / off signal related to the paper discharge alignment state is sent from a sensor (not shown) provided in the printing unit 2, plate making unit 3, paper feeding unit 4, plate discharging unit 5, paper discharge unit 6, image reading unit 7, and the like. The various signals are input.

The control means 55 controls each driving means (described later) of the printing unit 2, plate making unit 3, paper feeding unit 4, plate discharging unit 5, paper discharge unit 6, and image reading unit 7 based on the various signals inputted. To do. That is, the driving unit of the printing unit 2 includes the main motor 151 and the like. Examples of driving means for the plate making unit 3 include a master conveying stepping motor (not shown) and a cutter motor (not shown). As a driving unit for the paper feeding unit 4, a driving unit independent of the main motor 151 is used to rotationally drive the paper feeding roller 111, the separation roller 112a, and the registration rollers 113a and 113b. Examples thereof include a paper motor (not shown) and a registration motor (not shown) composed of a stepping motor, for example. As the driving means for the plate removal unit 5, a solenoid (not shown) that swings the plate release roller 71b, a plate release roller pair 71a, 71b, a plate transfer belt pair 72a, 72b, and a plate discharge motor that rotationally drives the plate release roller pair 73a, 73b. (Not shown). Examples of driving means for the paper discharge unit 6 include a suction paper discharge outlet roller 65 of the paper discharge suction conveyance unit 63, a paper discharge motor (not shown) that rotationally drives the conveyance belt 66, a suction fan 67, and the like. Examples of the driving means of the image reading unit 7 include a document conveying stepping motor (not shown).
Further, the control means 55 controls the operations of the speed indicator 45, the display unit 49A, and the liquid crystal display unit 49B of the operation panel 40, which are not shown in FIG. 4, based on various input signals. It also has a function.

The various signals input to the CPU 56 are arithmetically processed based on the operation program stored in the ROM 57, and the printing unit 2, the plate making unit 3, the paper feeding unit 4, the plate discharging unit 5, the paper discharging unit 6, and the image reading unit 7 are processed. Is output as an operation / command signal to each drive circuit for controlling the operation of the motor, and is also output as a display signal to the operation panel 40.
The CPU 56 is a case where the trailing edge of the stacked paper PA is detected by the stacked paper trailing edge detection sensors 14a, 14b based on the output signals from the stacked paper trailing edge detection sensors 14a, 14b, 14c. The liquid crystal display section 49B of the operation panel 40 differs depending on whether it is detected by only one of the edge detection sensors 14a and 14b or when detected by the two stacked paper trailing edge detection sensors 14a and 14b. It has a first control function for displaying / notifying warnings.
Further, the CPU 56 detects the trailing edge of the stacked paper PA in addition to the ON detection of the trailing edge of the stacked paper PA based on the output signals from the stacked paper trailing edge detection sensors 14a, 14b, and 14c. When the trailing edge of the stacked paper PA is detected by the edge detection sensor 14c, the stencil printing operation as an image forming operation is stopped, that is, the paper feeding unit 4, the printing operation, and the paper discharge operation are stopped. A second control function for stopping the operation of each of the driving means of the printing unit 2 and the paper discharge unit 6 is provided.

  The ROM 57 stores a plurality of operation programs for operating actuators such as motors and solenoids of the respective parts of the stencil printing apparatus 1. In the RAM 58, an operation program called from the ROM 57 by the CPU 56 is temporarily written, and the operation program is rewritten by an input from the operation panel 40. The RAM 58 also has a function of temporarily storing signals transmitted from the sensors, the CPU 56, and the like (the same applies to modified examples described later).

Next, control operations related to the paper discharge stacking apparatus 10 unique to the present embodiment other than the basic operation of the stencil printing apparatus 1 described above will be described. For the sake of simplicity, the CPU 56 of the control means 55 is sometimes simply referred to as the control means 55 (the same applies to modified examples described later).
As described above, the position of the end fence 12 and the side fences 13a and 13b is set in accordance with the paper size and printing is performed. However, when the printed paper P is discharged according to the paper type, the ratio of the print image area, the printing speed, and the like. The impact force is so strong that the shock absorption by the end fence 12 becomes incomplete, the paper discharge alignment due to the rebound of the printed paper P is deteriorated, and the paper is stacked on the paper discharge tray 11 with further deterioration. As a result, the sheet discharge alignment deteriorated to the level of artificial correction.
Specifically, as shown in FIG. 5, when the shock absorption at the end fence 12 is incomplete, and the stacked paper PA is slightly deviated from the regular paper discharge alignment position due to the rebound of the printed paper P or the like. When either one of the stacked paper trailing edge detection sensors 14a and 14b is turned on (the stacked paper trailing edge detection sensor 14b is turned on / detected in the paper discharge alignment state shown in FIG. 5), the control means 55 The CPU 56 displays a warning message “Please note that there is a paper skew state” on the liquid crystal display 49B of the operation panel 40. The user visually observes the warning display on the liquid crystal display unit 49B and pays attention to the subsequent printing / discharge operation.

  On the other hand, when the paper discharge alignment is further deteriorated, specifically, as shown in FIG. 6, when both the stacked paper trailing edge detection sensors 14a and 14b are turned on. Then, the CPU 56 of the control means 55 displays a warning display different from that described above on the liquid crystal display section 49B of the operation panel 40, that is, “the paper is in the paper back state, so the paper discharge alignment state is abnormal”. The user visually recognizes the warning displayed on the liquid crystal display unit 49B and continues the subsequent printing and discharging operation (for example, when the remaining number of printed sheets is small) or manually stops and discharges the paper. It is determined whether to correct the alignment (for example, when the remaining number of printed sheets is large).

Next, the shock absorption at the end fence 12 is further incomplete than shown in FIG. 6, and the stacked paper PA deviates more than the regular paper discharge alignment position due to the rebound of the printed paper P, and the like. In the case where the level has been deteriorated to a level that is artificially corrected and there is no user, conventionally, printed sheets P are stacked with the discharge alignment being deteriorated during printing, and the worst is The printing operation was stopped due to detection of a paper discharge jam or the like.
Therefore, in the present embodiment, the three sheets of trailing edge detection sensors 14a, 14b, and 14c detect a state in which the discharge alignment is deteriorated as described above to a level that requires artificial correction. That is, when both the stacked paper trailing edge detection sensors 14a and 14b are on and the stacked paper trailing edge detection sensor 14c is also turned on, the CPU 56 of the control means 55 performs a paper feeding operation, a printing operation, and a paper discharging operation. In addition to the automatic stop, the liquid crystal display 49B of the operation panel 40 indicates that “the printing operation has been stopped because the discharge alignment state is abnormal, so the discharge alignment is corrected and the necessary inspection / readjustment is performed. Please do so, etc. "warning is displayed. The user visually recognizes the warning displayed on the liquid crystal display unit 49B and adjusts / corrects the discharge.
Therefore, it goes without saying that according to the present embodiment, the above-described effects are produced.

(Modification 1 of the first embodiment)
7 and 8 show a first modification of the first embodiment. The modified example 1 is different from the stencil printing apparatus 1 of the first embodiment shown in FIGS. 1 to 6 in that a discharge stacking device 10A is used instead of the discharge stacking device 10 and the control means 55 is Instead, the point of using the control means 55A is mainly different.
Compared with the paper discharge stacking apparatus 10, the paper discharge stacking apparatus 10 </ b> A includes a sorting device 30 as a sorting unit that performs sorting by shifting the stacked paper PA stacked on the paper discharge tray 11 in the direction opposite to the paper discharge direction Y <b> 5. The only difference is the attached point. The modified example 1 is the same as the stencil printing apparatus 1 of the first embodiment except for the above differences.

  The sorting device 30 is a known device similar to the paper discharge sorting device shown in FIGS. 1 to 3 of JP-A-10-330019. That is, as shown in an enlarged and exaggerated manner in FIG. 7, the sorting device 30 is capable of advancing / retreating / contacting with the stacked paper PA stacked on the paper discharge tray 11 and picking up as a holding unit that holds the stacked paper PA at the leading end. A sheet moving slider 37 provided with a section 25, a moving table 35 that supports the sheet moving slider 37 so as to be able to move forward and backward, an elevating drive unit 32 that raises and lowers the moving table 35 in the vertical direction Z, and a sheet moving slider 37. And a slider advancing / retreating drive unit 36 that moves the paper in the paper discharge direction Y5 and the opposite direction.

The pickup unit 25 holds the set number of stacked sheets PA when the number of stacked sheets PA on the paper discharge tray 11 reaches the set number. At the leading end of the pickup unit 25 on the sheet discharge direction Y5 side, An inclination formed or coated with a material having a low coefficient of friction with respect to the paper for guiding the printed paper P, which is inclined downward and discharged toward the downstream side of the paper discharge direction Y5, to the end fence 12 side. A guide surface 26 and a hooking claw 27 protruding downward so as to bite into the set number of stacked sheets PA are formed. A rack 37 a is formed on the upper surface of the sheet moving slider 37 from the middle to the rear end of the pickup unit 25.
A sorting device bracket 31 is attached and fixed to the rear end portion (left end portion in FIG. 7) of the paper discharge tray 11. A lifting guide shaft 34 extending in the vertical direction is fixed to the sorting device bracket 31, and a guided hole (not shown) formed by penetrating the movable table 35 in the vertical direction Z by the lifting guide shaft 34. The movable table 35 is guided in the up-down direction Z via

  The elevating drive unit 32 is fixed to the output drive shaft of the elevating drive motor 32M, which is a stepping motor fixed to the sorting device bracket 31, and the female screw and screw formed on the moving table 35. It is mainly comprised from the raising / lowering drive shaft 33 in which the male screw to match was formed. The slider advancing / retreating drive unit 36 is fixed to the slide drive motor 36M composed of a stepping motor fixed to the moving table 35 via a motor bracket (not shown), and the output shaft of the slide drive motor 36M, and the sheet moving slider 37 is fixed. And a pinion 38 that meshes with the rack 37a.

  As described above, when the elevating drive motor 32M is driven to rotate the elevating drive shaft 33, the moving table 35 is lowered or raised together with the sheet moving slider 37 provided with the pickup unit 25 depending on the rotation direction. On the other hand, when the slide drive motor 36M is driven to rotate the pinion 38, the sheet moving slider 37 provided with the pickup unit 25 slides in the sheet discharge direction Y5 or the opposite direction depending on the rotation direction. When the pickup unit 25 of the sheet moving slider 37 is protruded from the sorting device bracket 31, an opening is formed in the sorting device bracket 31 for allowing the sheet moving slider 37 including the pickup unit 25 to move up and down. Has been.

  Compared with the control means 55 shown in FIG. 4, the control means 55 </ b> A of the first modification is different in that a CPU 56 </ b> A is used instead of the CPU 56 and a ROM 57 </ b> A is used instead of the ROM 57. In addition, as a control configuration for controlling the sorting device 30 of the first modification, a paper discharge sensor 69 is newly connected to the CPU 56A via an input port (not shown), and paragraph “0030” of JP-A-10-330019. The other difference is that various sensors similar to those described in the above are connected to the CPU 56A via an input port (not shown).

Since various sensors similar to those described in paragraph “0030” of Japanese Patent Laid-Open No. 10-330019 are publicly known, only the reference numerals are given in parentheses for explanation, and in the block diagram shown in FIG. It is represented as a sensor included in the device 30. That is, a home position sensor (42) for detecting the home position (initial position) shown in FIG. 7 at which the pickup unit 25 is farthest from the paper discharge table 11 is provided at an input port (not shown) of the control means 55A shown in FIG. A first stroke sensor (43) for detecting a state in which the pickup unit 25 is located at the most advanced position advanced in the paper discharge direction Y5, and a pickup position in which the pickup unit 25 is retracted by a predetermined distance from the most advanced position. The second stroke sensor (44) for detecting the position, the upper limit sensor (45) for detecting the home position (initial position) in which the movable base 35 is raised to the uppermost initial position, and the pickup unit 25 eject the paper. A paper sensor (46) for detecting the state of reaching the set number of stacked papers SA on the table 11 is connected.
The home position sensor (42), the first stroke sensor (43), and the second stroke sensor (44) are provided on the moving table 35, and the upper limit sensor (45) is located near the moving table 35. The sheet sensor (46) is provided on a non-illustrated immovable member on the side, and the sheet sensor (46) detects the sheet in the pickup unit 25 so that the pickup unit 25 descends together with the moving table 35 and detects the uppermost stacked sheet PA on the sheet discharge table 11. It is fixed by using the lower surface or the like on the discharge direction Y5 side.
Further, the lifting drive motor 32M and the slide drive motor 36M of the sorting device 30 are connected to an output port (not shown) of the control means 55A via each drive circuit (not shown). The control configuration shown in FIG. 8 is the same as the control configuration shown in FIG. 4 except for the differences described above.

The various signals input to the CPU 56A of the control means 55A are processed based on the operation program stored in the ROM 57A, and the printing unit 2, the plate making unit 3, the paper feeding unit 4, the plate discharging unit 5, the paper discharging unit 6, In addition to being output as an operation / command signal to each drive circuit that controls the operation of the image reading unit 7 and the sorting device 30, it is also output as a display signal to the operation panel 40.
The CPU 56A has a first control function similar to that of the CPU 56 shown in FIG. That is, the CPU 56A includes a home position sensor (42), a first stroke sensor (43), a second stroke sensor (44), an upper limit sensor (45), a paper sensor (46), a paper discharge sensor 69, and a post-stacked paper. When the trailing edge of the stacked paper PA is detected by at least one of the stacked paper rear edge detection sensors 14a, 14b based on the output signals from the edge detection sensors 14a, 14b, 14c, the pickup unit of the sorting device 30 25 vertical plane portions (refer to the plane formed substantially perpendicular to the lower end of the inclination of the inclined fitting surface 26 and the paper discharge guide surface 11a formed on the catching claw 27 in FIG. 7) in the paper carry-out direction Y5. The elevating drive motor 32M and the slide drive motor 36M are controlled so as to correct the stacked paper PA shifted in the opposite direction.
Further, the CPU 56A has a second control function similar to that of the CPU 56 shown in FIG.

  The ROM 57A stores a plurality of operation programs for operating actuators such as motors and solenoids of the above portions of the stencil printing apparatus 1 and motors 32M and 36M of the sorting device 30. Specifically, when the trailing edge of the stacked paper PA is detected by at least one of the stacked paper trailing edge detection sensors 14a and 14b, the ROM 57A corresponds to the number of printed sheets of the stacked paper SA. Height dimension data indicating the height (mm) of the stacked sheet SA in the vertical direction Z from the discharge stacking surface 11a of the discharge table 11 and the vertical plane portion of the pickup unit 25 are raised and lowered to that height. Data relating to the number of pulses applied to the lifting drive motor 32M is stored in advance. Similarly, in the ROM 57A, when the trailing edge of the stacked paper PA is detected by at least one of the stacked paper trailing edge detection sensors 14a and 14b, the stacked paper corresponding to the number of printed sheets of the stacked paper SA. Data relating to the number of pulses to be applied to the slide drive motor 36M for correcting the movement of SA to the regular discharge alignment position on the discharge stacking surface 11a is stored in advance.

Next, a control operation related to the paper discharge stacking device 10 </ b> A specific to this modification other than the basic operation of the stencil printing apparatus 1 described above will be described. Since the original sorting operation of the sorting apparatus 30 is the same as that described in paragraphs “0031” to “0036” of the above-mentioned JP-A-10-330019, the description thereof is omitted. The feature of this modification is that it automatically corrects the deteriorated state of the paper discharge alignment using a part of the sorting operation by the sorting device 30. Therefore, a description will be given focusing on this.
As described above, the position of the end fence 12 and the side fences 13a and 13b is set in accordance with the paper size and printing is performed. However, when the printed paper P is discharged according to the paper type, the ratio of the print image area, the printing speed, and the like. The impact force is so strong that the shock absorption by the end fence 12 becomes incomplete, the paper discharge alignment due to the rebound of the printed paper P is deteriorated, and the paper is stacked on the paper discharge tray 11 with further deterioration. As a result, the sheet discharge alignment deteriorated to the level of artificial correction.
Specifically, as shown in FIGS. 5 and 7, the shock absorption at the end fence 12 becomes incomplete, and the stacked paper PA is slightly more than the regular paper discharge alignment position due to the rebound of the printed paper P or the like. When there is a deviation and when either one of the stacked paper trailing edge detection sensors 14a and 14b is turned on, the CPU 56A of the control means 55A performs the following control operation.
That is, the CPU 56A prints the number of printed sheets SA from the ROM 57A based on the output signals from the home position sensor (42), the upper limit sensor (45, the sheet discharge sensor 69, and the stacked sheet trailing edge detection sensors 14a, 14b, and 14c. Corresponding to the eyes, the number of pulses applied to the raising / lowering drive motor 32M for raising and lowering the vertical plane portion of the pickup unit 25 from the discharge stacking surface 11a to its height is extracted and the number of prints of the stacked paper SA Correspondingly, the number of pulses applied to the slide drive motor 36M for correcting the movement of the stacked paper SA to the regular discharge alignment position on the discharge stacking surface 11a is extracted, and the lift drive motor 32M and the slide drive are extracted. By controlling the drive motor 36M, the vertical plane portion of the pickup unit 25 is opposite to the paper carry-out direction Y5. By automatically moving correction to the paper discharge justification normal deviation was loaded sheet PA in, so that the deterioration of the alignment paper discharge is suppressed.
In addition, a warning message is displayed on the liquid crystal display section 49B of the operation panel 40 to the effect that “the paper skew state has been corrected automatically”. The user pays attention to the subsequent printing / discharge operation by appropriately viewing the warning display on the liquid crystal display unit 49B.

On the other hand, when the paper discharge alignment is further deteriorated, specifically, as shown in FIGS. 6 and 7, both the stacked paper rear end detection sensors 14a and 14b are turned on. Even when the paper is jammed, the CPU 56A of the control means 55A executes the same control as described above, so that the stacked paper PA in which the vertical plane portion of the pickup unit 25 is shifted in the direction opposite to the paper carry-out direction Y5 is automatically removed. By correcting the movement to the regular paper discharge alignment position, it is possible to suppress the deterioration of the paper discharge alignment.
Further, a warning display different from the above-described one is displayed on the liquid crystal display unit 49B of the operation panel 40, and a warning display saying that “the paper discharge state is abnormal in the paper back state and has been automatically corrected”. The user appropriately recognizes the warning display on the liquid crystal display unit 49B and continues the subsequent printing / discharge operation.

Next, the shock absorption at the end fence 12 is further incomplete than shown in FIG. 6, and the stacked paper PA is largely deviated from the normal paper discharge alignment position due to the rebound of the printed paper P and the like. In the case where the level has been deteriorated to the level of artificial correction, that is, when both the stacked paper trailing edge detection sensors 14a and 14b are on and the stacked paper trailing edge detection sensor 14c is also on, the control is performed. The CPU 56A of the means 55A automatically stops the paper feeding operation, the printing operation, and the paper ejection operation as in the first embodiment, and the liquid crystal display unit 49B of the operation panel 40 indicates that “the paper ejection alignment state is abnormal. Therefore, the printing operation is stopped, so correct the paper discharge alignment and perform necessary inspections and readjustments ". The user visually recognizes the warning displayed on the liquid crystal display unit 49B and adjusts / corrects the discharge.
Therefore, it goes without saying that according to the first modification, the above-described effects can be obtained.

(Modification 2 of the first embodiment)
9 to 11 show a second modification of the first embodiment. The modification 2 is different from the stencil printing apparatus 1 of the first embodiment shown in FIGS. 1 to 6 in that a paper discharge stacking device 10B is used instead of the paper discharge stacking device 10, and the control means 55 is different. Instead, the main difference is that the control means 55B is used.
Compared with the paper discharge stacking apparatus 10, the paper discharge stacking apparatus 10B uses an end fence 15 shown in FIG. 9 and FIG. 10 in place of the end fence 12, and is attached to the end fence 15, and the paper discharge direction Y5 or The only difference is that it has an angle adjustment mechanism 183 and a rotation mechanism 184 as angle adjustment means capable of adjusting the standing angle of the end fence 15 with respect to the paper discharge stacking surface 11a. Modification 2 is the same as the stencil printing apparatus 1 of the first embodiment except for the above differences.

As shown in FIGS. 9 and 10, the end fence 15 includes an end fence main body 16 having a rectangular horizontal cross section, an end fence bracket 178 for attaching to a slider of an end fence position adjusting mechanism (not shown) on the discharge table 11, An angle adjustment mechanism 183 and a rotation mechanism 184 are included.
The end fence main body 16 has shock absorbing members 16A (for example, large paper sizes: A3 to B5), 16B (for example, large paper sizes: A3 to B5), 16C (for example, small papers) displayed by hatching corresponding to the paper size. Size: postcard, envelope, etc.) and 16D (for example, small paper size: postcard, envelope, etc.) are provided.
Further, the impact absorbing members 16B and 16D have an elastic modulus (high hardness) corresponding to thin paper, improve the impact absorbability at the time of collision when the thin paper is discharged, and the paper is bent by the impact at the time of collision. Suppresses unstable paper fall. On the other hand, the impact absorbing members 16A and 16C have a modulus of elasticity (low hardness) higher than that of thin paper, corresponding to thick paper and standard paper, and have a similar fall instability suppressing function. . This is because the elastic force corresponding to the thin paper has an impact force that is too strong and the shock absorption becomes incomplete, which promotes the deterioration of the paper discharge alignment due to the rebound of the paper.
The “shock absorbing member” here is not only configured to be added as a separate body to the end fence body 16, but also when the surface layer itself of each surface of the end fence body 16 is processed to give shock absorption. It is a concept that includes. For example, it includes a case where the end fence body 16 is made of a rubber-based material and each surface is processed to change the elastic modulus.
The end fence main body 16 when supporting a size (postcard, envelope, etc.) smaller than the standard size is in front of the rotation reference bracket 110 (position of the extension bracket 117) (on the upstream side in the paper discharge direction Y5) 16C. Alternatively, the shock absorbing members 16 </ b> C and 16 </ b> D are extended downward in order to compensate for the difference in position with the rotation reference bracket 110.

As shown in FIGS. 9 and 10, the present modification has an angle adjustment mechanism 183 and a rotation mechanism 184, and is characterized in that the rotation and angle adjustment of the end fence body 16 are automated.
As shown in FIGS. 9 and 10, a rotation reference bracket 110 is attached and fixed to an extension bracket 117 formed to extend downward from the lower portion of the end fence body 16. The end fence bracket 178 and the rotation reference bracket 110 are connected to each other by a pin 116 via a vertical piece 178a formed integrally with the end fence bracket 178. Therefore, the end fence main body 16 is supported at two points by the pin 116 and a shaft portion 154b of the angle adjusting shaft 154 described later with respect to the end fence bracket 178.

The angle adjustment mechanism 183 includes an angle adjustment bracket 153, an angle adjustment shaft 154, a stepping motor 155, and the like. An angle adjustment bracket 153 is attached to the back side of the rotation reference bracket 110. The angle adjustment bracket 153 is formed by bending a metal plate into a substantially S-shaped cross section, and has a mounting portion 153a. The mounting portion 153a is screwed to the back surface of the rotation reference bracket 110, and appropriately bonded or the like. It is fixed by the method.
A stepping motor 155 having a pinion 155a fixed to an output shaft is attached to the upper surface 153b of the angle adjustment bracket 153, and the angle adjustment shaft 154 is rotatably supported by an intermediate surface 153c parallel to the upper surface 153b. The bearing 153d is provided with a window portion 153f in the flat surface portion 153e, and a hole portion (not shown) through which the angle adjusting shaft 154 passes through the lower surface 153g.

The angle adjustment shaft 154 includes a screw portion 154a having a male screw formed on the outer peripheral surface and a shaft portion 154b having a female screw into which the screw portion 154a is screwed. The screw portion 154a is an angle adjustment bracket. The tip of the shaft portion 154b is brought into contact with the upper surface of the end fence bracket 178 while being supported by the bearing 153d of 153.
A gear 156 that meshes with the pinion 155a is integrally provided at the upper end portion of the screw portion 154a, and an index 158 that is fitted into the window portion 153f is integrally provided at the upper end portion of the shaft portion 154b. In addition, a home position sensor 159 that detects the initial position of the index 158 is provided on the flat surface portion 153e.

With the above-described configuration, the stepping motor 155 is driven to transmit the rotational driving force to the angle adjustment shaft 154 via the pinion 155a and the gear 156, and the screw portion 154a is screwed into the shaft portion 154b to thereby rotate the angle adjustment shaft 154. When the screw portion 154a is moved up and down in the vertical direction Z to reduce the screwing amount of the screw portion 154a into the shaft portion 154b, the end fence body 16 is tilted clockwise in FIG. 10, and the screw portion 154a is screwed into the shaft portion 154b. Is increased, the end fence body 16 is tilted counterclockwise in FIG.
Accordingly, for example, when the end fence body 16 is positioned at the position shown in FIGS. 9 and 10, the end fence body 16 is set so that the index 158 is detected by the home position sensor 159 and the stepping motor 155 is driven. The angle and position can be controlled.

The rotation mechanism 184 includes a stepping motor 130 fixed to the end fence body 16, a drive gear 131 fixed to the rotation shaft of the stepping motor 130, and a shaft with a slit having a flange on the upper surface fixed to the rotation reference bracket 110. 132, a small-diameter fixed gear 133 that is integrally formed on the upper surface of the flange of the shaft 132 with slits and meshes with the drive gear 131, and fixed to the end fence body 16, and detects the slit of the shaft 132 with slits to determine the reference position. It has a position sensor 134 and the like for detection.
The drive gear 131 of the stepping motor 130 revolves while rotating around the fixed gear 133, whereby the end fence body 16 is rotated. As the end fence body 16 rotates, the position sensor 134 also rotates, and a reference position can be detected by detecting a slit (not shown) formed on the flange of the shaft 132 with the slit.
When the shock absorbing members 16A to 16D of the end fence main body 16 are automatically switched based on the paper information, control corresponding to the paper size described above is performed. In this modification, the rotation mechanism 184 is omitted from the block diagram shown in FIG. 11 and the operation thereof, in order to simplify the explanation, particularly by using the angle adjustment mechanism 183 of the end fence 15. The description is also limited to the above-described content.

Compared with the control means 55 shown in FIG. 4, the control means 55 </ b> B of the second modification is different from the control means 55 </ b> B in that a CPU 56 </ b> B is used instead of the CPU 56 and a ROM 57 </ b> B is used instead of the ROM 57. A home position sensor 159 is connected to an input port (not shown) of the control means 55B shown in FIG.
Further, a stepping motor 155 of the angle adjusting mechanism 183 is connected to an output port (not shown) of the control means 55B via a drive circuit (not shown). The control configuration shown in FIG. 11 is the same as the control configuration shown in FIG. 4 except for the differences described above.

The various signals input to the CPU 56B of the control means 55B are subjected to arithmetic processing based on the operation program stored in the ROM 57B, and the printing unit 2, the plate making unit 3, the paper feeding unit 4, the plate discharging unit 5, the paper discharging unit 6, The image reading unit 7 and the angle adjustment mechanism 183 are each output as an operation / command signal to each drive circuit that controls the operation, and are also output as a display signal to the operation panel 40.
The CPU 56B has a first control function similar to that of the CPU 56 shown in FIG. 4 and also has the following specific control function. That is, the CPU 56B uses the output signals from the home position sensor 159 and the stacked paper trailing edge detection sensors 14a, 14b, and 14c to cause the trailing edge of the stacked paper PA by at least one of the stacked paper trailing edge detection sensors 14a and 14b. When the end is detected, the stepping motor 155 is controlled so that the angle of the end fence 15 is adjusted to a position and angle at which the impact energy (collision force) of the printed paper P can be absorbed.
The CPU 56B has a second control function similar to that of the CPU 56 shown in FIG.

The ROM 57B stores a plurality of operation programs for operating the motors, solenoids, and other actuators of the above portions of the stencil printing apparatus 1 and the stepping motor 155 of the angle adjustment mechanism 183.
That is, the number of pulses applied to the stepping motor 155 related to the angle of the end fence body 16 in the end fence 15 corresponds to the discharge speed of the discharge suction conveyance unit 63 that changes in proportion to the printing speed of the stencil printing apparatus 1. For example, it is set to automatically position at positions and angles corresponding to paper discharge speeds 1 to 5 corresponding to printing speed levels 1 to 5 (60 rpm (sheets / minute) to 120 rpm), respectively. . For example, when the position / angle shown in FIG. 10 is the home position of the end fence 15, the position / angle is gradually changed in the counterclockwise direction in FIG. It is set to an angle.

More specifically, the inclination of the end fence body 16 is related to the degree of shock absorption when the printed paper P collides with the end fence body 16, as shown in FIG. 9 and FIG. When the end fence body 16 is located at the most upstream side in the paper discharge direction Y5, the degree of impact absorption is small, and the angle is gradually changed in the counterclockwise direction in FIG. When it is located on the downstream side in the direction Y5, there is much absorption of impact.
Therefore, when the discharge speed of the discharge suction conveyance unit 63 is the first speed, which is the slowest, the end fence body 16 is positioned at the position shown in FIG. It is possible to prevent the occurrence of deterioration of the paper discharge alignment due to the fact that the printed paper P does not fall from the leading edge due to being excessively absorbed by appropriately absorbing the impact.
Further, when the discharge speed of the discharge suction conveyance unit 63 is the fifth speed, the end fence body 16 is positioned counterclockwise from the position and angle shown in FIG. It is possible to prevent the deterioration of the paper discharge alignment due to the printed paper P being bounced back or bent without being absorbed, by reliably absorbing the impact.

Next, a control operation related to the paper discharge stacking device 10 </ b> B specific to the present modification other than the basic operation of the stencil printing apparatus 1 described above will be described. The feature of this modification is that the angle adjustment mechanism 183 of the end fence 15 is used to automatically correct the deteriorated state of the paper discharge alignment. Therefore, a description will be given focusing on this.
As described above, the position of the end fence 15 and the side fences 13a and 13b is set in accordance with the paper size and printing is performed. However, when the printed paper P is discharged depending on the paper type, the ratio of the print image area, the printing speed, and the like. The impact force is so strong that the shock absorption by the end fence 15 becomes incomplete, the paper discharge alignment due to the rebound of the printed paper P is deteriorated, and the paper is stacked on the paper discharge tray 11 with further deterioration. As a result, the sheet discharge alignment deteriorated to the level of artificial correction.
Specifically, as shown in FIGS. 5 and 7, the shock absorption at the end fence 15 becomes incomplete, and the stacked paper PA is slightly more than the regular paper discharge alignment position due to the rebound of the printed paper P or the like. When there is a deviation, and when any one of the stacked paper trailing edge detection sensors 14a and 14b is turned on, the following control operation is performed by the CPU 56B of the control means 55B.

That is, the CPU 56B uses the output signals from the home position sensor 159 and the stacked paper trailing edge detection sensors 14a, 14b, and 14c to cause the trailing edge of the stacked paper PA by at least one of the stacked paper trailing edge detection sensors 14a and 14b. When the end is detected, the number of pulses applied to the stepping motor 155 for adjusting the angle of the end fence 15 is extracted from the ROM 57B to a position and angle at which the impact energy (collision force) of the printed paper P can be absorbed. By controlling the stepping motor 155, the angle of the end fence 15 is set to a position / angle at which the impact energy of the printed paper P can be absorbed, specifically, an angle preset in the counterclockwise direction in FIG. By performing the adjustment automatically, it is possible to suppress the deterioration of the paper discharge alignment.
In addition, a warning message is displayed on the liquid crystal display section 49B of the operation panel 40 to the effect that “the paper skew state has been corrected automatically”. The user pays attention to the subsequent printing / discharge operation by appropriately viewing the warning display on the liquid crystal display unit 49B.

On the other hand, when the paper discharge alignment is further deteriorated, specifically, as shown in FIGS. 6 and 7, both the stacked paper rear end detection sensors 14a and 14b are turned on. Even when it is jammed, the CPU 56B of the control means 55B executes the same control as described above, so that the angle adjustment of the end fence 15 is automatically adjusted to the position / angle where the impact energy of the printed paper P can be absorbed. By doing so, the deterioration of the paper discharge alignment is suppressed.
Further, a warning display different from the above-described one is displayed on the liquid crystal display unit 49B of the operation panel 40, and a warning display saying that “the paper discharge state is abnormal in the paper back state and has been automatically corrected”. The user appropriately recognizes the warning display on the liquid crystal display unit 49B and continues the subsequent printing / discharge operation.

Next, the impact absorption at the end fence 15 is further incomplete than described with reference to FIG. 6, and the stacked paper PA deviates more than the regular paper discharge alignment position due to the rebound of the printed paper P. In the event that the level has finally deteriorated to the level of artificial correction, that is, both the stacked paper trailing edge detection sensors 14a and 14b are on, and the stacked paper trailing edge detection sensor 14c is also on. At times, the CPU 56B of the control means 55B automatically stops the paper feeding operation, the printing operation, and the paper ejection operation as in the first embodiment and the first modification, and the liquid crystal display unit 49B of the operation panel 40 The warning message stating “Because the printing operation has been stopped due to abnormal paper discharge alignment status, please correct the paper discharge alignment and perform necessary inspections and readjustments”. It is. The user visually recognizes the warning displayed on the liquid crystal display unit 49B and adjusts / corrects the discharge.
Therefore, it goes without saying that according to the second modification, the above-described effects can be obtained. The angle adjusting mechanism 183 of the end fence 15 is not limited to this, and any angle adjusting means can be used as long as the angle of the end fence can be automatically changed / set.

The embodiments and modifications of the present invention have been applied to the stencil printing apparatus 1 as described above. However, the present invention is not limited to this, and is not limited to this. Printing apparatuses other than the stencil printing apparatus 1, ink jet recording apparatuses, printers, plotters, and the like. The present invention can also be applied to an image forming apparatus having a function such as a copying machine or a facsimile, or a discharge sheet stacking apparatus (discharge stacking apparatus) provided in an image forming apparatus such as a multi-function apparatus having a plurality of functions.
The sheet / sheet-like recording medium is not limited to the paper P, and includes, for example, special paper such as coated paper, an OHP sheet, and the like, and printing or image formation may be performed using this.
In addition, the following terms can be rephrased as superordinate conceptual terms. That is, the paper discharge direction is the sheet discharge direction, the paper is the sheet, the paper discharge table is the discharge sheet stacking table, the paper width direction is the sheet width direction, and the paper discharge stacking device is the discharge sheet stacking device.
As described above, the present invention has been described with respect to specific embodiments and modifications including examples. However, the present invention is not limited to the above-described embodiments and modifications, and these may be combined as appropriate. It will be apparent to those skilled in the art that various embodiments and examples can be configured within the scope of the present invention in accordance with the necessity and application thereof.

It is a front view of the whole stencil printing machine provided with the paper discharge stacking apparatus which shows the 1st Embodiment of this invention. It is a top view of the operation panel used for 1st Embodiment etc. FIG. 3 is a plan view illustrating a main part of the paper discharge stacking apparatus according to the first embodiment. It is a block diagram which shows the control structure of the principal part of the stencil printing apparatus in 1st Embodiment. It is a top view which shows the state which detected the skew state of the stacking paper by one of the three stacking paper rear end detection sensors in the first embodiment. FIG. 6 is a plan view showing a state in which the back state of the stacked paper is detected by two of the three stacked paper trailing edge detection sensors in the first embodiment and the like. FIG. 10 is a schematic front view illustrating the periphery of a sorting device in a paper discharge stacking device according to Modification 1; FIG. 10 is a block diagram showing a control configuration of a main part of a stencil printing apparatus in Modification 1; It is a figure which shows the end fence in the paper discharge | stacking stacking apparatus of the modification 2, its angle adjustment mechanism, etc., (a) is sectional drawing of the principal part, (b) is sectional drawing of (a). FIG. 10 is an enlarged cross-sectional view of an end fence angle adjusting mechanism and the like in FIG. It is a block diagram which shows the control structure of the principal part of the stencil printing apparatus in the modification 2.

Explanation of symbols

1 Stencil printing device (printing device / image forming device)
2 Printing section (image forming means)
4 Paper feed unit 6 Paper discharge unit (discharge unit)
10, 10A, 10B Paper discharge stacking device 11 Paper discharge table 11a Paper discharge stacking surface 14a, 14b, 14c Stacked paper rear end detection sensor (rear end position detection means)
12, 15 End fences 13a, 13b A pair of side fences 30 Sorting device (sorting means)
32M lift drive motor (first drive means of sorting means)
36M slide drive motor (second drive means of sorting means)
40 Operation panel (operation unit)
49B Liquid crystal display (notification means / display means)
55, 55A, 55B control means 56, 56A, 56B CPU
61 Master 183 Angle adjustment mechanism (angle adjustment means)
P paper (sheet / sheet-like recording medium)
PA Loaded paper Y5 Paper discharge direction X Paper width direction Z Height direction / vertical direction

Claims (8)

A paper discharge tray on which image-formed paper discharged in the paper discharge direction is sequentially stacked; an end fence that can be adjusted in the paper discharge direction on the paper discharge table; and the paper discharge on the paper discharge stand. In a paper discharge stacking apparatus comprising a pair of side fences that are capable of adjusting the position in the paper width direction orthogonal to the direction and provided opposite to each other,
A plurality of trailing edge position detecting means for detecting the trailing edge position of sheets stacked on the discharge tray on,
At least two of the plurality of rear end position detecting means are configured to cause the paper discharge in the vicinity of the rear end position of the paper exposed from the rear end of the paper stacked on the paper discharge stand in a normal paper discharge alignment state. Discharge stacking device characterized by being arranged on a table . In the paper discharge stacking apparatus according to claim 1,
At least two of the plurality of rear end position detecting means are disposed within the paper width of the minimum size paper to be used and on substantially the same straight line in the paper width direction. Paper output stacking device. The paper discharge stacking apparatus according to claim 2.
Having an informing means for informing information,
When the trailing edge of the sheet is detected by the at least two trailing edge position detecting means and detected by only one of the at least two trailing edge position detecting means, the two edges are detected. The paper discharge stacking apparatus is characterized in that the notification means makes a different notification depending on when the paper is discharged. In the paper discharge stacking device according to any one of claims 1 to 3 ,
An angle adjusting means capable of adjusting an angle of the end fence with respect to the paper carry-out direction;
The paper discharge stacking apparatus, wherein when the trailing edge of the sheet is detected by at least one of the at least two trailing edge position detecting means, the angle adjusting means adjusts the angle of the end fence. . In the paper discharge stacking device according to any one of claims 1 to 4 ,
Sorting means for sorting the paper loaded on the paper discharge tray in a direction opposite to the paper carrying-out direction;
When the trailing edge of the sheet is detected by at least one of the at least two trailing edge position detecting means, the sorting means causes the correction of the sheet shifted in the direction opposite to the sheet carrying-out direction. A discharge stacking device. In the paper discharge stacking device according to any one of claims 1 to 5 ,
At least one of the plurality of rear end position detecting means is disposed at a position closer to the rear end than the vicinity of the rear end position . An image forming apparatus having an image forming unit that forms an image on a sheet, and a discharge unit that discharges the image-formed sheet onto the discharge table.
7. An image having the sheet discharge stacking apparatus according to claim 6, wherein the image forming operation is stopped when a rear end of the sheet is detected by a rear end position detecting unit disposed at a position near the rear end. Forming equipment . An image forming apparatus having an image forming unit that forms an image on a sheet, and a discharge unit that discharges the image-formed sheet onto the discharge table.
An image forming apparatus comprising the paper discharge stacking device according to claim 1 .

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