JP2001163506A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely align paper sheets by a side fence and an end fence sliding automatically even if the paper sheet discharged to a paper discharge part is a nonstandard size. SOLUTION: When the paper sheet discharged to the paper discharge part is the nonstandard size, the side fence of the paper discharge part is slid to a position corresponding to the lateral width size in the direction crossing at right angles with the paper discharge direction of the paper. When the length dimension of the paper in the paper discharge direction is larger than the prescribed dimension, the end fence of the paper discharge part is slid to the maximum slide position and, when being smaller than the prescribed dimension, it is slid to a position corresponding to the prescribed dimension. Therefore, when either of the nonstandard size paper whose length dimension in the direction along the paper discharge direction is a prescribed dimension or less or the nonstandard size paper whose length dimension in the direction along the paper discharge direction is a prescribed dimension or more is discharged, the tip of the paper in the discharge direction is made to abut on the end face so as to surely align the paper sheets.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus in which a sheet fed from a sheet feeding section is conveyed along a conveying path and discharged to a sheet discharging section, and a desired image is formed on the sheet in the conveying process. It relates to a forming device.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus having a structure in which a sheet is conveyed along a conveying path from a sheet feeding section to a sheet discharging section and a desired image is formed on the sheet in the conveying process, a printer,
Copiers, printing machines and the like are known. In these image forming apparatuses, various fixed-size sheets or irregular-size sheets are used.

Further, some of these image forming apparatuses include a side fence which is slidable in a direction orthogonal to a sheet discharging direction of a sheet to be discharged, and a side fence which is slidable in a direction along the sheet discharging direction of the sheet to be discharged. Some end fences are provided in the paper discharge section. By sliding these side fences and end fences to a position corresponding to the size of the paper to be discharged to the paper discharge unit, the sheets discharged to the paper discharge unit and stacked can be stacked on the side fence and the end fence. This facilitates post-processing of the sheets that have been aligned and discharged to the discharge unit.

As a method of sliding the side fence and the end fence, there are a manual method and an automatic method using a motor or the like.

In the case of a method in which the side fence and the end fence are manually slid, the sliding operation is troublesome and troublesome.

In a system in which a side fence and an end fence are slid by a motor or the like, the side fence and the end fence are slid according to a detection result of a sensor for detecting the size of a sheet provided in a sheet feeding unit. Structures are known. Specifically, a plurality of width detection sensors that detect a width in a direction perpendicular to the paper feeding direction of the paper placed on the paper feeding unit, and a plurality of width detection sensors in the paper feeding direction of the paper placed on the paper feeding table. One length detecting sensor for detecting whether or not the length dimension along the direction is equal to or larger than a predetermined dimension is provided in the sheet feeding unit, and based on the detection results of the width detecting sensor and the length detecting sensor, It is determined whether the paper on the paper feed unit is a standard size or an irregular size. Then, when it is determined that the sheet has a standard size, the side fence and the end fence are slid to a position corresponding to the standard size. On the other hand, if it is determined that the paper is of an irregular size, the side fence is slid to the position corresponding to the detection result of the width detection sensor, and the end fence is moved to the maximum slide position (mostly from the paper discharge port in the paper discharge unit). To the remote slide position).

[0007]

In the above-described system in which the side fence and the end fence of the paper discharge unit are automatically slid by a motor or the like, when the paper to be used is of an irregular size, The end fence always slides to the maximum sliding position irrespective of the size of the length in the direction along the sheet discharging direction. For this reason, when a sheet of irregular size having a small length in the direction along the sheet discharging direction is discharged, the discharged sheet reaches the position where the leading end of the discharged sheet hits the end fence. Instead, the stop position of the leading end of the discharged paper in the paper discharge direction varies,
A situation occurs in which the discharged sheets are remarkably varied along the sheet discharging direction.

The present invention relates to an image forming apparatus employing a system in which a side fence and an end fence of a paper discharge section are automatically slid by a motor or the like in accordance with the size of paper to be discharged. Image that ensures that the leading end of the ejected paper in the paper ejection direction hits the end fence even when paper is ejected, and that the paper can be aligned well in the direction along the paper ejection direction of the ejected paper. It is an object to provide a forming device.

[0009]

According to the first aspect of the present invention,
In an image forming apparatus that conveys a sheet fed from a sheet feeding unit along a conveyance path and discharges the sheet to a sheet discharging unit, and forms a desired image on the sheet in the conveying process, the sheet is placed on the sheet feeding unit. A plurality of width detection sensors for detecting a width in a direction perpendicular to a paper feeding direction of the placed paper; and a length dimension in a direction along a paper feeding direction of the paper placed on the paper feeding unit. A length detection sensor for detecting whether or not is greater than or equal to a predetermined dimension; and a slide provided in the paper discharge unit and slid in a direction perpendicular to a paper discharge direction of the paper discharged to the paper discharge unit. A freely movable side fence, a side fence drive unit connected to the side fence and sliding the side fence, and a side fence drive unit provided in the paper discharge unit and extending along a paper discharge direction of the paper discharged to the paper discharge unit. End fence that can slide in the direction And the end fence drive unit for being coupled to the command fence Slide this end fence,
A fixed-size / unfixed-size determining means for determining whether the sheet placed on the sheet feeding unit is a fixed-size or a non-fixed-size based on detection results of the width detection sensor and the length detection sensor; and When it is determined that the side fences and the end fence slide to a position corresponding to the standard size, the side fence drive unit and the end fence drive unit control a fixed size paper control unit. And, when it is determined that the paper is irregular size, while controlling the side fence drive unit so that the side fence slides to a position according to the detection result of the width detection sensor, the paper When the length detection sensor detects that the length dimension in the direction along the paper feeding direction is equal to or less than a predetermined dimension, the end fence is moved to the length. When the length detection sensor detects that the length dimension in the direction along the paper feeding direction by sliding to the position corresponding to the installation position of the knowledge sensor is greater than a predetermined dimension, the end fence is raised to the maximum. Irregular-shaped paper control means for controlling the end fence drive unit to slide to the slide position.

Here, "the end fence slides to a position corresponding to the installation position of the length detection sensor" means that the distance from the paper feed port in the paper feed unit to the position where the length detection sensor is provided. This means that the dimensions from the paper discharge port of the paper discharge unit to the position where the end fence slides are the same.

The phrase "the end fence slides to the maximum slide position" means that the slide position of the end fence is the position farthest from the discharge port in the discharge section.

Therefore, when a sheet used in the image forming apparatus is placed on the sheet feeding section, it is determined whether the sheet is a fixed size or an irregular size based on detection results from the width detection sensor and the length detection sensor. It is determined by the indeterminate determination means.
If it is determined that the paper to be used has the standard size, the side fence and the end fence slide to positions corresponding to the standard size. Therefore, when a sheet of a standard size is used, the sheet can be reliably aligned by the side fence and the end fence when the sheet is discharged.

On the other hand, when it is determined that the paper to be used is of an irregular size, the side fence slides to a position corresponding to the detection result of the width detection sensor. As a result, the side fence can reliably perform the alignment of the discharged sheets in the width direction orthogonal to the discharge direction.

The position of the end fence to be slid is different depending on whether the length detection sensor is on or off. The length detection sensor determines that the length of the end fence in the sheet feeding direction is equal to or smaller than a predetermined size. When the end fence is detected, the end fence slides to a position corresponding to the installation position of the length detection sensor. As described above, when a sheet having a small length in the sheet feeding direction is ejected to the sheet ejection unit, the end fence is located at a position not far from the sheet ejection port of the sheet ejection unit, and the sheet is ejected. Since the leading end of the paper in the paper discharge direction hits the end fence and is stopped, and the paper in the paper discharge direction is reliably aligned, it is possible to prevent a situation in which the discharged paper greatly varies along the paper discharge direction. You.

When the length detecting sensor detects that the length in the direction along the paper feeding direction is equal to or larger than a predetermined size, the end fence slides to the maximum sliding position. As described above, when a sheet having a large length dimension in the sheet discharging direction is discharged to the sheet discharging unit, the end fence slides to the maximum sliding position, so that the leading end of the discharged sheet in the sheet discharging direction becomes the end fence. And the paper is aligned in the paper discharge direction.

According to a second aspect of the present invention, a sheet fed from a sheet feeding unit is conveyed along a conveying path and discharged to a sheet discharging unit, and a desired image is formed on the sheet during the conveying process. In the image forming apparatus, a plurality of width detection sensors that detect a width in a direction orthogonal to a paper feeding direction of the paper placed on the paper feeding unit, and a sensor for detecting the width of the paper loaded on the paper feeding unit. A plurality of length detection sensors for detecting a length dimension in a direction along a paper feeding direction; and a direction orthogonal to the paper discharging direction of the paper provided in the paper discharging unit and discharged to the paper discharging unit. A side fence that is slidable to the side fence, a side fence drive unit that is connected to the side fence and slides the side fence, and a discharge direction of the sheet that is provided in the discharge unit and discharged to the discharge unit End fen that can slide in the direction along And an end fence drive unit coupled to the end fence to slide the end fence, and a side controlling the side fence drive unit to slide the side fence to a position according to the detection result of the lateral width detection sensor. Fence control means; and end fence control means for controlling the end fence drive unit such that the end fence slides to a position corresponding to the detection result of the length detection sensor.

Therefore, when a sheet used in the image forming apparatus is placed on the sheet feeding section, a width dimension in a direction perpendicular to the sheet feeding direction is detected by the width detecting sensor, and the direction along the sheet feeding direction is detected. Is detected by the length detection sensor. Then, the side fence slides to a position corresponding to the detection result of the width detection sensor, and the end fence slides to a position corresponding to the detection result of the length detection sensor. For this reason, even if the sheet has a fixed size or an irregular size, the sheet alignment by the side fence and the end fence can be reliably performed.

[0018]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. FIG. 1 is a vertical sectional front view showing the entire structure of a stencil printing machine as an image forming apparatus. Since the basic structure of a stencil printing machine is well known,
The basic structure will be described briefly. This stencil printing machine includes an optical reading unit 1, a stencil making unit 2, a printing unit 3, a stencil discharging unit 4, a paper feeding unit 5,
It comprises a paper discharge unit 6 and the like.

The optical reading section 1 has a structure as a digital scanner for optically reading an image of a document (not shown).

The plate making section 2 makes a master 7 by heating and melting and punching a master base paper according to the image data read by the optical reading section 1, cuts the master 7 into a predetermined length, and cuts the master 7 into a printing section 3. Send out.

The printing unit 3 is driven to rotate around an axis, and has a porous cylindrical plate cylinder 8 around which a master 7 is wound. The press roller is movable to a position which comes into contact with and separates from the outer peripheral surface of the plate cylinder 8. 9, an ink supply unit (not shown) provided inside the plate cylinder 8; In the printing unit 3, the paper 10 fed from the paper feeding unit 5 is sandwiched between the plate cylinder 8 around which the master 7 is wound and the press roller 9, and at this time, the paper 10 is supplied from the ink supply unit into the plate cylinder 8. The printing is performed by transferring the applied ink to the paper 10 by oozing from the perforated portion of the master 7.

The plate discharging section 4 has a structure in which a used master 7 that has become unnecessary after printing of a predetermined number of sheets is peeled off from the outer peripheral surface of the plate cylinder 8 and the peeled master 7 is stored.

The paper feed unit 5 separates and feeds the papers 10 stacked on the paper feed table 11 and feeds them into the plate cylinder 8 and the press rollers 9.
It is the structure that leads between. The sheet 10 guided between the plate cylinder 8 and the press roller 9 on which printing has been performed is transferred to the suction conveyance unit 1.
The paper is sucked and conveyed by 2 and is discharged to the paper discharge unit 6. A transport path 13 through which the paper 10 is transported is formed between the paper supply unit 5 and the paper discharge unit 6.

FIG. 6 is a block diagram showing the electrical connection of the control system. The operation of each unit described above is performed by the control system shown in FIG. This control system is a control device 1 having a microcomputer configuration including a CPU and a memory (not shown).
4 as main components, and a main switch 15, an operation panel 16, an optical reading unit 1, a plate making unit 2, a printing unit 3, a plate discharging unit 4, a paper feeding unit 5, and a paper discharging unit 6 are provided in the control device 14. Are connected to each other.

Next, a paper supply / discharge mechanism including the paper supply unit 5 and the paper discharge unit 6 will be described. FIG. 2 is a perspective view showing the paper feeding unit 5, and FIG. 3 is a perspective view showing a structure for detecting the size of the paper 10 placed on the paper feeding table 11. Paper feed table 11
A pair of sheet feeding side fences 17 which are located opposite to each other are attached, and these sheet feeding side fences 17 are slidably provided in a direction orthogonal to the sheet feeding direction of the sheet 10. Further, the paper feed table 11 has four width detection sensors 18a, 18b, and 4 for detecting the width of the paper 10 placed on the paper feed table 11 in the direction perpendicular to the paper feed direction.
18c, 18d, one length detecting sensor 19 for detecting whether or not the length of the paper 10 placed on the paper feed table 11 in the paper feeding direction is equal to or larger than a predetermined size; A paper presence / absence detection sensor 20 for detecting whether or not the paper 10 is placed on the paper feed table 11 is attached. The width detection sensors 18a to 18d are light transmission type sensors, and the length detection sensor 19 and the paper presence / absence detection sensor 20 are light reflection type sensors, both of which are connected to the control device 14 and turned on / off by the control device 14. A signal is given to detect the size and presence / absence of the paper 10 placed on the paper feed table 11.

More specifically, a plurality of light-shielding plates 17a slidable integrally with the sheet feeding side fence 17 are fixed below the sheet feeding side fence 17 in a predetermined pattern. Then, according to the sliding position of the sheet feeding side fence 17, the light shielding plates 17a shield the four width detection sensors 18a to 18d in a predetermined pattern, and furthermore, the length detection sensor 19 senses a total of five detections. The output patterns of the sensors 18a to 18d and 19 change. Based on the output patterns of the detection sensors 18a to 18d and 19, the size of the paper 10 placed on the paper feed table 11 is a regular size, an irregular size, or a regular size. Has a structure in which something is recognized by the control device 14.

FIG. 4 is a plan view showing the paper discharge unit 6. The paper discharge unit 6 is provided with a paper discharge table 21. The paper discharge table 21 includes a pair of side fences 23 slidably mounted on a guide rail 22 via a slider 23 a, and a slider 25 a on the guide rail 24. And an end fence 25 slidably attached thereto. The side fence 23 is provided for the paper 10 to be discharged onto the discharge tray 21.
The end fence 25 is slidable in a direction (arrow a in FIGS. 4 and 5) orthogonal to the paper discharge direction of the sheet 10 (arrow b in FIGS. 4 and 5). Direction) can slide freely.

FIG. 5 is a plan view in which the sheet discharge table 21 is cut away to show the sliding structure of the side fence 23 and the end fence 25. The pair of side fences 23
It is connected to a rack and pinion mechanism 29 composed of a pinion gear 26 rotatably mounted on the back surface of the guide rail 22 and a rack 28 guided by a slide guide 27 mounted on the back surface of the guide rail 22, and slides in conjunction with each other. I do. The pinion gear 26 includes a timing belt 30
The worm gear mechanism 31 is connected to the worm gear mechanism 31 via a DC motor 32 which is a side fence driving unit. The DC motor 32 is connected to the control device 14.

The end fence 25 is connected to a DC motor 35 serving as an end fence driving unit via a worm gear mechanism 33 and a rack and pinion mechanism 34. The DC motor 35 is connected to the control device 14.

The paper output tray 21 includes a paper presence / absence detection sensor 36 which is a light reflection type sensor for detecting the presence / absence of the paper 10 on the paper output tray 21, and a side fence for controlling the sliding position of the side fence 23. The position sensors 37a,
37b, 37c, 37d and an end fence position sensor 3 for controlling the slide position of the end fence 25
8a, 38b, 38c, 38d, 38e are provided,
Each is connected to the control device 14.

Side fence position sensors 37a-37d
Is one rack 2 in the rack & pinion mechanism 29
8 is a light reflection type sensor for detecting the presence or absence of a protruding piece 39 protruding from 8. The facing distance H between the side fences 23 is 182 mm (B5 vertical size) when the sensor 37a among the side fence position sensors 37a to 37d is on,
When the sensor 37b is on, 210 mm (A4 vertical size), and when the sensor 37c is on, 257 mm (B4
(Vertical, B5 horizontal size), 2 when sensor 37d is on
97 mm (A3 vertical, A4 horizontal).

End fence position sensors 38a to 38e
Is a light reflection type sensor for detecting the presence or absence of a protruding piece 40 protruding from the rack in the rack & pinion mechanism 34. The suitable paper length L of the paper discharge tray 21 determined by the position of the end fence 25 is the end fence position sensor 3
8a to 38e, when the sensor 38a is on, 2
10 mm (B5 horizontal, A4 horizontal), 257 mm (B5 vertical) when the sensor 38b is on, and the sensor 38
297 mm (A4 vertical size) when c is on, 364 mm (B4 vertical size) when sensor 38d is on, and 420 mm (A3 vertical) when sensor 38e is on.
Vertical).

When the sensor 38e is turned on, the end fence 25 is moved to the maximum sliding position (the paper discharge unit 6).
At the position farthest from the paper discharge port at the time of the printing). Further, when the projecting piece 40 is detected by the end fence position sensor 38a,
The dimension from the paper discharge port to the end fence 25 is the same as the dimension from the paper supply port in the paper supply unit 5 to the position where the length detection sensor 19 is provided.

Here, the stencil printing machine according to the present embodiment includes a fixed / indeterminate determination means as various means executed by the microcomputer operation of the control device 14,
It has a fixed form paper control means and an irregular form paper control means.

The fixed-form / unfixed-form judging means judges whether the paper 10 placed on the paper feed tray 11 is a regular size or an irregular size, and is accompanied by placing the paper 10 on the paper feed tray 11. A detection signal from the length detection sensor 19 and detection from the width detection sensors 18a to 18d caused by sliding the paper supply side fence 17 to a position corresponding to the width of the paper 10 placed on the paper supply table 11. The control signal is input to the control device 14 and the control device 14 determines whether the paper 10 has a standard size or an irregular size based on the detection signals.

When it is determined that the paper 10 has the standard size, the standard paper control means drives the DC motors 32 and 35 to move the side fence 23 and the end fence 25 to a predetermined position corresponding to the size of the paper 10. Slide to. As a result, the side fence 23 performs sheet alignment in the direction orthogonal to the sheet discharge direction of the discharged sheet 10, and the end fence 25 performs sheet alignment in the direction along the sheet discharge direction of the discharged sheet 10. Done. The detection that the side fence 23 has slid to the predetermined position is performed by the side fence position sensors 37a to 37d.
The detection that the end fence 25 has slid to the predetermined position is performed by the end fence position sensors 38a to 38e.
It is performed by

When the paper 10 is determined to be of an irregular size, the irregular-shaped paper control means controls the DC motors 32 and 3.
5 to drive the side fence 23 and end fence 2
5 is slid to a predetermined position. The sliding of the side fence 23 when the paper 10 has an irregular size is performed to a position corresponding to the detection result of the width detecting sensors 18a to 18d of the paper feeding unit 5. Thus, the side fence 23 performs sheet alignment in a direction orthogonal to the sheet discharge direction of the discharged sheet 10. The slide position of the end fence 25 differs depending on whether the length detection sensor 19 of the sheet feeding unit 5 is off or on.

When the length detecting sensor 19 is off, the end fence 25 slides to a position where the protruding piece 40 is detected by the end fence position sensor 38a. The fact that the length detection sensor 19 is turned off indicates that the sheet feeder 1
This means that the length dimension of the paper 10 placed in 1 in the paper feeding direction is smaller than the dimension from the paper feeding port in the paper feeding unit 5 to the position of the length detection sensor 19. As described above, when the paper 10 having a small length in the paper discharge direction is discharged to the paper discharge unit 6, the end fence 25 is located at a position not far from the paper discharge port of the paper discharge unit 6, When the leading end of the discharged sheet 10 in the sheet discharging direction collides with the end fence 25, the sheet is stopped, and the sheets are aligned in the sheet discharging direction. For this reason, the leading end of the discharged sheet 10 in the sheet discharging direction does not reach the position where it hits the end fence 25, and the stop position of the leading end of the discharged sheet 10 varies, and the discharged sheet 10 Can be prevented from significantly fluctuating along the sheet discharging direction.

When the length detecting sensor 19 is ON, the end fence 25 slides to a position where the protruding piece 40 is detected by the end fence position sensor 38e (the maximum sliding position of the end fence 25). Length detection sensor 19
Is turned on, it means that the length of the paper 10 placed on the paper supply table 11 in the paper supply direction is the size from the paper supply port of the paper supply unit 5 to the position of the length detection sensor 19. Means greater. As described above, when the paper 10 having a large length dimension in the paper discharging direction is discharged to the paper discharging unit 6, the end fence 25 is located at a position far away from the paper discharging port of the paper discharging unit 6, so that the paper is discharged. When the leading end of the paper sheet 10 in the paper discharge direction hits the end fence 25, the paper 1
0 does not come out of the paper discharge port, and the leading end of the discharged paper 10 in the paper discharge direction hits the end fence 25, so that the paper 10
Is performed in the paper discharge direction.

Accordingly, when the irregularly sized paper 10 is ejected, the end fence 25 can perform excellent sheet alignment regardless of the length of the paper 10 in the ejection direction. In addition, it is not necessary to provide a new length detection sensor in the paper feeding unit 5 or the like for this paper alignment, and one length detection sensor 19 used for detecting the standard size of the paper 10 is used. You just need to use

Next, control for automatically sliding the side fence 23 and the end fence 25 to a position corresponding to the size of the sheet 10 to be discharged will be described.

FIG. 7 shows the paper 10 placed on the paper feed table 11.
5 is a flowchart showing a process for obtaining the dimension data of FIG. When the main switch 15 of the stencil printing machine is turned on, it is determined whether or not the paper presence / absence detection sensor 20 of the paper feeding unit 5 is on (step S1). Paper feed table 11
When the paper 10 is present above, the paper presence / absence detection sensor 20 is turned on, and when there is no paper 10, the paper presence / absence detection sensor 20 is turned off. When the paper presence / absence detection sensor 20 is ON, the detection signals from the width detection sensors 18a to 18d and the length detection sensor 19 are input to the control device 14, and are temporarily stored in the registration unit of the control device 14 (step). S2).

FIG. 8 is a flowchart illustrating the slide control of the side fence 23 and the end fence 25 performed when the print start key is pressed.
When the print start key is pressed, it is determined whether or not the paper presence / absence detection sensor 20 of the paper feed unit 5 is turned on (step S
3) and whether or not the sheet presence / absence detection sensor 36 of the sheet discharging unit 6 is turned off (step S4). Then, the sheet presence sensor 20 is turned on because the sheet 10 is placed on the sheet supply table 11 (Y in step S3), and the sheet presence detection is performed because the sheet 10 is not on the sheet discharge table 21. When the sensor 36 is off (Y in step S4), a detection signal is called from the registration unit (step S5).

When the sheet presence sensor 20 is off because the sheet 10 is not placed on the sheet supply table 11 (N in step S3), a display (not shown) provided on the operation panel 16 Is displayed on the screen (step S
6) The placement of the paper 10 on the paper feed table 11 is prompted. If the paper presence / absence detection sensor 36 is ON because the paper 10 remains on the paper discharge tray 21 (N in step S4), a paper discharge reset display is displayed on the display of the operation panel 16 (step S7). The removal of the sheet 10 from the sheet discharge table 21 is prompted.

When the detection signal is called from the registration unit (step S5), whether the paper 10 on the paper feed table 11 is the standard size or the irregular size is determined based on the detection signal. A judgment is made (step S8), and here, a fixed form / unfixed form determining means is executed.

If it is determined that the paper 10 on the paper feed table 11 is of a standard size (Y in step S8), any of the side fence position sensors (37a to 37d) corresponding to the standard size of the paper 10 is used. 1) and the end fence position sensor (any one of 38a to 38d) are selected (Step S9), and the selected side fence position sensor and end fence position sensor are respectively set to the projecting pieces 3
DC motors 32 and 3 are detected until the DC motors are turned on and detected.
5 is driven (steps S10 and S11), and the fixed-size sheet control means is executed by the processing of steps S9 to S11. By the execution of the fixed sheet control means, the side fence 23 and the end fence 25 slide to a position corresponding to the fixed size of the sheet 10 discharged onto the sheet discharge tray 21, and the side fence 23 and the end fence 2 are moved.
5, the paper 10 discharged onto the paper discharge table 21 is aligned.

If it is determined that the paper 10 on the paper feed table 11 is of an irregular size (N in step S8), any of the side fence position sensors (37a to 37d) corresponding to the width of the paper 10 is used. Is selected (step S12), and the DC motor 35 is driven until the selected side fence position sensor detects the protruding piece 39 and turns on (steps S13 and S14). Further, it is determined whether or not the length detection sensor 19 is on (step S15).

If the length detection sensor 19 is on (Y in step S15), the end fence position sensor 3
The DC motor 35 is driven until 8e detects the protruding piece 40 and turns on (steps S16 and S17). on the other hand,
When the length detection sensor 19 is off (step S15)
N), the end fence position sensor 38a
Is detected and the DC motor 35 is driven until it is turned on (steps S18, S19). Then, the irregular-size sheet control means is executed by the processing of steps S12 to S19 described above. Due to the execution of the irregular-shaped sheet control means, the side fence 23 slides to a position corresponding to the width of the sheet 10 discharged onto the sheet discharge table 21 and the end fence 2
Reference numeral 5 slides to a position where the protruding piece 40 is detected by the end fence position sensor 38a or to a maximum sliding position where the protruding piece 40 is detected by the end fence position sensor 38e.

In such a configuration, in the stencil printing machine of the present embodiment, when the paper 10 is placed on the paper feed table 11, the width of the paper 10 in the direction orthogonal to the paper feed direction and the paper feed The length dimension in the direction along the direction is detected by the width detection sensors 18 a to 18 d and the length detection sensor 19. If it is determined that the paper 10 has the standard size, the side fences 23 and the end fence 25 on the paper output tray 21 are driven by the DC motors 32 and 35 to correspond to the size of the paper 10. Slide to position. As a result, the sheet 10 discharged onto the discharge tray 21
Is the side fence 23 in the width direction orthogonal to the paper discharge direction.
And the direction along the sheet discharging direction is aligned by the end fence 25.

On the other hand, if it is determined that the paper 10 placed on the paper feed table 11 is of an irregular size, the side fence 23 sets the paper 10 in accordance with the detection result of the width detecting sensors 18a to 18d. Is driven by the DC motor 32 and slid to a position corresponding to the lateral width dimension of. This allows
The side fence 23 performs sheet alignment in the width direction orthogonal to the sheet discharge direction of the sheet 10 discharged onto the sheet discharge table 21.

When it is determined that the paper 10 placed on the paper feed table 11 has an irregular size, the end fence 25 determines whether the length detection sensor 19 is off or on.
That is, the slide position of the end fence 25 is changed depending on whether the length of the sheet 10 in the direction along the sheet feeding direction (sheet discharging direction) is shorter or longer than a predetermined size. Then, when the length detection sensor 19 is off (when the length of the paper 10 in the paper feeding direction (paper discharging direction) is shorter than a predetermined size).
In the case where the end fence 25 slides to a position close to the paper discharge port of the paper discharge unit 6 and the length detection sensor 19 is turned on (the length of the paper 10 in the paper feed direction (paper discharge direction) is If it is longer, the end fence 25 slides to a position (maximum sliding position) farthest from the discharge port of the discharge unit 6.

Thus, in the case of the irregularly sized paper 10 whose length in the paper feeding direction (paper discharging direction) is shorter than the predetermined size, when the paper 10 is discharged onto the paper discharge table 21,
The paper 10 hits the end fence 25 sliding to a position close to the paper discharge port and stops, thereby performing paper alignment in the paper discharge direction. For this reason, it is prevented that the discharged paper 10 does not reach the position where it hits the end fence 25 and fluctuates significantly in the paper discharge direction. Further, in the case of the paper 10 of an irregular size whose length in the paper feeding direction (paper discharging direction) is longer than a predetermined dimension, when the paper 10 is discharged, the paper 10 is furthest from the paper discharge port. When the end fence 25 is slid to the maximum sliding position, which is the maximum sliding position, the stop is performed, and the paper is aligned in the paper discharging direction.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. 1 to 8 are denoted by the same reference numerals,
Description is also omitted. FIG. 9 is a plan view showing the sheet feeding unit 5. In the present embodiment, four width detection sensors 18a and 18 for detecting the width of the paper 10 placed on the paper feed table 11 in the direction orthogonal to the paper feed direction are provided on the paper feed table 11.
b, 18c, 18d, and the paper 1 placed on the paper feed table 11
Five length detection sensors 41a, 41b, 41c, 41 for detecting the length dimension in the direction along the paper feeding direction of 0
d and 41e, and a paper presence / absence detection sensor 20 for detecting whether or not the paper 10 is placed on the paper feed table 11 are attached. The length detection sensors 41 a to 41 e are light reflection type sensors, and are all connected to the control device 14.

As in the first embodiment, the side fence 23, the end fence 25, and
Side fence position sensors 37a to 37d and end fence position sensors 38a to 38e are provided.

In this embodiment, the control unit 14 has side fence control means and end fence control means as various means executed by the microcomputer operation. The side fence control means is a process of driving the DC motor 32 so that the side fence 23 slides to a position according to the detection results of the width detection sensors 18a to 18d. The end fence control means drives the DC motor 35 so that the end fence 25 slides to a position corresponding to the detection results of the length detection sensors 41a to 41e.

FIG. 10 shows the sheet 1 placed on the sheet feeding table 11.
9 is a flowchart illustrating a process for obtaining dimension data of 0. When the main switch 15 of the stencil printing machine is turned on, it is determined whether or not the paper presence / absence detection sensor 20 of the paper feeding unit 5 is on (step S21). Paper feed table 1
When the paper 10 is on the sheet 1, the paper presence / absence detection sensor 20 is turned on, and when there is no paper 10, the paper presence / absence detection sensor 20 is turned off. When the paper presence / absence detection sensor 20 is on, the width detection sensors 18a to 18d and the length detection sensors 41a to 41d
The detection signal from the controller 41e is input to the controller 14 and is temporarily stored in the registration unit of the controller 14 (Step S
22).

FIG. 11 is a flowchart illustrating the slide control of the side fence 23 and the end fence 25 performed when the print start key is pressed. The processing of steps S23 to S27 is the same as the processing of steps S3 to S7 described in FIG.

When the detection signal is called from the registration unit (step S25), the side fence position corresponding to the width and length of the paper 10 on the paper feed table 11 is determined based on the detection signal. Sensors (any one of 37a to 37d) and end fence position sensors (38a to 3d)
8d) (step S2).
8). Thereafter, the selected side fence position sensor and end fence position sensor are respectively connected to the projecting pieces 39 and 4.
The DC motors 32 and 35 are driven until 0 is detected and turned on (steps S29 and S30), and the processing of steps S28 to S30 executes the side fence control means and the end fence control means.

In such a configuration, in this embodiment, when the paper 10 is placed on the paper feed table 11, the paper 1
0 is detected by the width detection sensors 18a to 18d, and the length of the paper 10 in the direction along the paper feeding direction is detected by the length detection sensors 41a to 41d.
e. Then, the width detecting sensors 18a to 18
The side fence 23 is slid to a position corresponding to the detection result of d, and the end fence 25 is slid to a position corresponding to the detection result of the length detection sensors 41a to 41e. Therefore, regardless of whether the paper 10 is of a standard size or an irregular size, the direction orthogonal to the sheet discharging direction is aligned by the side fence 23, and the direction along the sheet discharging direction is aligned by the end fence 25. Is done.

In the present embodiment, the case where the light reflection type length detecting sensors 41a to 41e are provided on the sheet feeding table 11 has been described as an example, but the rear end portion of the placed sheet 10 is described. And a paper feed end fence that can slide freely to
A reflection-type length detection sensor for detecting the slide position of the paper feed end fence may be provided.

[0061]

According to the image forming apparatus of the first aspect of the present invention, when the paper discharged to the paper discharge section is a sheet of a standard size, the side fence and the end fence of the paper discharge section are connected. The sheet can be slid to a position corresponding to the fixed size, and the fixed size paper can be reliably aligned.
If the paper to be discharged to the paper discharge unit is a sheet of irregular size, slide the side fence to a position corresponding to the width in the direction orthogonal to the paper discharge direction, and then set the paper discharge direction. If the length of the paper is smaller than the specified dimension, slide the end fence to the position corresponding to the specified dimension. Position, so that even when discharging a sheet of irregular size whose length in the direction along the sheet discharging direction is equal to or less than a predetermined dimension, the leading end of the sheet in the sheet discharging direction is brought into contact with the end fence. Paper alignment can be performed reliably.

According to the image forming apparatus of the present invention, the width of the paper placed on the paper feeding section in the direction perpendicular to the paper feeding direction is detected by the width detecting sensor, and the paper feeding direction is detected. The length dimension in the direction along is detected by the length detection sensor, and the side fence of the paper discharge unit slides to the position corresponding to the detection result of the width detection sensor, and moves to the position corresponding to the detection result of the length detection sensor. Since the end fence of the paper discharge unit slides, ensure that the side fence and the end fence align the paper regardless of whether the paper discharged to the paper discharge unit is of a standard size or irregular size. Can be.

[Brief description of the drawings]

FIG. 1 is a front view showing the entire structure of a stencil printing machine according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a paper discharge unit.

FIG. 3 is a perspective view illustrating a structure for detecting a size of a sheet placed on a sheet feeding table.

FIG. 4 is a plan view showing a paper discharge unit.

FIG. 5 is a plan view of the paper discharge tray cut away to show a slide structure of a side fence and an end fence.

FIG. 6 is a block diagram illustrating electrical connection of each unit.

FIG. 7 is a flowchart illustrating a process for obtaining dimension data of a sheet placed on a sheet feeder.

FIG. 8 is a flowchart illustrating slide control of a side fence and an end fence.

FIG. 9 is a plan view illustrating a structure of a sheet feeding unit according to a second embodiment of the present invention.

FIG. 10 is a flowchart illustrating a process for obtaining dimension data of a sheet placed on a sheet feeder.

FIG. 11 is a flowchart illustrating slide control of a side fence and an end fence.

[Explanation of symbols]

 Reference Signs List 5 paper feeding unit 6 paper discharging unit 10 paper 13 transport path 18a to 18d plural width detecting sensors 19 one length detecting sensor 23 side fence 25 end fence 32 side fence driving unit 35 end fence driving unit 41a to 41e plural Length detection sensors

Claims (2)

[Claims] An image forming apparatus configured to convey a sheet fed from a sheet feeding unit along a conveyance path and discharge the sheet to a sheet discharge unit, and to form a desired image on the sheet in the conveyance process; A plurality of width detection sensors for detecting a width in a direction perpendicular to a paper feeding direction of the paper placed on the paper feeding unit; 1 to detect whether the length dimension in the direction is equal to or greater than a predetermined dimension
A length fence sensor, a side fence provided in the paper discharge unit and slidable in a direction orthogonal to a paper discharge direction of the paper discharged to the paper discharge unit; A side fence drive unit for sliding the side fence; an end fence provided in the paper discharge unit and slidable in a direction along a paper discharge direction of the paper discharged to the paper discharge unit; An end fence drive unit connected to the end fence to slide the end fence, based on the detection results of the width detection sensor and the length detection sensor, whether the paper placed on the paper feeding unit is a standard size or an irregular size. When the paper is determined to be of a standard size, the side fence and the side fence are moved to a position corresponding to the standard size. If the the command fence is determined and sized sheet control means for controlling the said end fence drive unit and the side fence driving unit so as to slide, and the paper is a custom size,
The side fence driving unit is controlled so that the side fence slides to a position corresponding to the detection result of the width detection sensor, and a length dimension in a direction along a sheet feeding direction of the sheet is equal to or smaller than a predetermined dimension. When the length detection sensor detects that, the end fence is slid to the position corresponding to the installation position of the length detection sensor, and the length dimension in the direction along the paper feeding direction of the paper is a predetermined dimension or more. Image forming means for controlling the end fence driving section so as to slide the end fence to a maximum sliding position when the length detection sensor detects that apparatus. 2. An image forming apparatus which conveys a sheet fed from a sheet feeding unit along a conveying path and discharges the sheet to a sheet discharging unit, and forms a desired image on the sheet in the conveying process. A plurality of width detection sensors for detecting a width in a direction perpendicular to a paper feeding direction of the paper placed on the paper feeding unit; A plurality of length detection sensors for detecting a length dimension in a direction, and a side fence provided in the paper discharge unit and slidable in a direction orthogonal to a paper discharge direction of the paper discharged to the paper discharge unit. A side fence drive unit connected to the side fence to slide the side fence; and provided in the paper discharge unit and slid in a direction along a paper discharge direction of the paper discharged to the paper discharge unit. A flexible end fence and the end fence An end fence drive unit connected to the fence to slide the end fence, and a side fence control unit that controls the side fence drive unit so that the side fence slides to a position according to the detection result of the lateral width detection sensor. And an end fence control unit that controls the end fence driving unit so that the end fence slides to a position corresponding to a detection result of the length detection sensor.