JPH08290859A - Sheet discharge device of stencil duplicator - Google Patents

Abstract

PURPOSE: To provide a sheet discharge device of a stencil duplicator to improve sheet arrangement and to prevent occurrence of set-off, picture image stain, etc. CONSTITUTION: It is furnished with a picture image printing part to print a picture image by means of transferring ink to a sheet 3, a sheet stiffening part provided in the sheet discharging direction of this picture image printing part and to stiffen the sheet 3, a sheet discharge tray 31 provided in the sheet discharging direction of this sheet stiffening part and a pair of side plates 44 arranged on this sheet discharge tray 31 with an interval narrower than width of the sheet 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet discharging device for a stencil printing machine.

[0002]

2. Description of the Related Art In a stencil printing machine, a master having a thermoplastic resin film is heat-perforated, wound around a porous cylindrical plate cylinder, and then the ink in the plate cylinder is passed through the holes of the master. Is transferred to the paper to continuously print on the paper. In addition, the ink used contains a large amount of water so that it quickly penetrates into the paper and dries after being transferred to the paper.In general, water is dispersed in oil to prevent evaporation. W /
It is an O-type emulsion ink. Therefore, when the ink is transferred to the paper, the water content of the ink permeates the fiber portions of the paper to expand the fibers of the paper, the printing surface side to which the ink is transferred extends, and the paper warps in a convex shape.

Therefore, the printing surface of the paper is curved in a concave shape,
As a sheet discharging device for supporting a sheet on a sheet and discharging the sheet to a sheet discharging tray, there is one disclosed in JP-A-60-148866. In this paper discharge device, a paper discharge passage having jump plates at both side edges on the paper discharge tray side is provided in the paper discharge direction of the plate cylinder, and a suction fan is provided below the paper discharge passage. Then, the central portion of the paper is attracted to the paper discharge path by the suction fan, both side edges of the paper are pushed up by the jump plate, the printing surface of the paper is bent in a concave shape, and the paper is discharged to the paper discharge tray.

[0004]

However, in the paper discharge device disclosed in Japanese Unexamined Patent Publication No. 60-148866, for example, as shown in FIG. 9, a space equal to the paper width A on the paper discharge tray 1. The pair of side plates 2 is arranged in the. Therefore, the paper 3 discharged to the paper discharge tray 1 is
By the time the ink drops, the printing surface (the upper surface in FIG. 9) of the paper 3 expands until it falls onto the paper discharge tray 1, and the paper 3 warps in a convex shape. As a result, the escape of air from the lower surface of the sheet 3 becomes unstable, and the sheet 3 violates while falling. Therefore, there is a problem that the discharged sheet alignment becomes worse, and the sheets 3 have to be aligned when sorting after printing is completed or when a post-processing device such as a collator or a sorter is used, which is very troublesome. Is. In addition, since the paper 3 is violent while falling, rubbing occurs between the previously discharged paper 3 and the newly discharged paper 3, and the ink of the previously discharged paper 3 becomes new. There is a problem that the sheet is transferred to the lower surface of the sheet 3 and the show-through occurs, or the printing surface of the sheet 3 that was previously discharged is rubbed and the image is soiled. In particular, when printing is performed with many solid images, the amount of ink transferred to the paper is large, so that show-through and image smearing easily occur.

The present invention has been made in view of the above problems, and provides a sheet discharge device of a stencil printing apparatus which improves alignment of sheets and prevents the occurrence of show-through and image stains. With the goal.

[0006]

According to the first aspect of the present invention,
An image printing unit that transfers ink to the paper to print an image, a paper backing unit that is provided in the paper ejection direction of the image printing unit, and is provided in the paper ejection direction of the paper backing unit A paper discharge tray and a pair of side plates arranged on the paper discharge tray at intervals smaller than the width of the paper are provided.

According to a second aspect of the present invention, in the sheet discharge device of the stencil printing apparatus according to the first aspect, a thickness detecting means for detecting the thickness of the sheet and the thickness of the sheet detected by the thickness detecting means. Based on this, the side plate arranging means arranges the pair of side plates at an interval narrower than the width of the sheet or substantially equal to the width of the sheet.

According to a third aspect of the present invention, in the paper discharge device of the stencil printing apparatus according to the first aspect, thickness detecting means for detecting the thickness of the sheet, and the thickness of the sheet detected by the thickness detecting means. Based on this, side plate disposing means for disposing a pair of side plates at an arbitrary interval between an interval narrower than the width of the sheet and an interval substantially equal to the width of the sheet.

According to a fourth aspect of the present invention, in the paper discharge device of the stencil printing apparatus according to the first, second or third aspect, size detecting means for detecting the size of the portion of the paper to which the ink has been transferred, And a side plate disposing means for narrowing the distance between the pair of side plates based on the size of the portion of the paper on which the ink has been transferred detected by the size detecting means.

The invention of claim 5 is the invention of claims 1, 2, and 3.
Alternatively, in the paper discharge device of the stencil printing machine described in 4, the friction coefficient of the side surface of the pair of side plates with which the paper is in contact is reduced.

The invention according to claim 6 is the same as claims 1, 2 and
In the paper discharge device of the stencil printing machine according to 3, 4, or 5,
The upper portions of the pair of side plates on the side of the paper waist portion were bent outward.

The invention according to claim 7 is the invention as claimed in claim 1,
In the sheet discharging device of the stencil printing machine described in 3, 4, or 5, the upper parts of the pair of side plates were bent outward.

[0013]

According to the first aspect of the present invention, the pair of side plates are provided at intervals smaller than the width of the sheet, and both side edges of the sheet are dropped while being abutted against the side surfaces of the side plate. The printing surface can be dropped while curving in a concave shape, and it is possible to prevent the paper from moving violently during falling, improving the paper alignment and newly ejecting the previously ejected paper. The rubbing against the printed paper is prevented, and the occurrence of show-through and image stains is prevented.

According to the second aspect of the present invention, based on the thickness of the sheet detected by the thickness detecting means, when the side plate arranging means makes the sheet thin and the sheet itself has a weak stiffness, the gap is narrower than the width of the sheet. With a pair of side plates, when the paper is thick and the paper itself is strong, a pair of side plates are arranged at intervals almost equal to the width of the paper, so that the paper is thick and the paper itself is strong. However, since it is possible to prevent excessive resistance when dropping while keeping it in contact with the side surface of the side plate, the paper drops stably, and the paper that was ejected earlier and newly Contact with the discharged paper is prevented, and jamming is prevented.

According to the third aspect of the present invention, based on the thickness of the sheet detected by the thickness detecting means, when the side plate arranging means makes the sheet thin and the sheet itself has a weak stiffness, the gap is narrower than the width of the sheet. When a pair of side plates is installed on the paper, and the paper is thick and the paper itself is strong, a pair of side plates is installed at intervals approximately equal to the width of the paper, and the paper is neither thick nor thin, When the paper is neither strong nor weak, by disposing the pair of side plates at an arbitrary interval between the space narrower than the width of the paper and the space almost equal to the width of the paper according to the thickness of the paper, It is possible to prevent excessive resistance when dropping any kind of paper, from strong to weak, with the side plate of the side plate abutting, so that the paper is safe. To fall, contact with the paper that is newly discharge the paper is discharged previously is prevented, occurrence of a jam can be prevented.

According to the fourth aspect of the invention, the ink on the paper is transferred by the side plate arranging means based on the size of the portion on the paper to which the ink is transferred detected by the size detecting means. The gap between the pair of side plates becomes narrower as the area becomes larger, and the paper is dropped while curving the printing surface of the paper in a concave shape by dropping both side edges of the paper while contacting the side surfaces of the side plates. Since it is possible to prevent the paper from moving violently while falling, the alignment of the paper is improved even when the ink transfer portion on the paper becomes large and the stiffness of the paper becomes weak, and Rubbing between the previously discharged sheet and the newly discharged sheet is prevented, and the occurrence of show-through, image stains, etc. is prevented.

According to the fifth aspect of the present invention, by lowering the friction coefficient of the side surface of the side plate with which the sheet abuts, the side edges of the sheet are dropped while abutting the side plate side surface. Since the resistance can be reduced, the paper drops stably, the contact between the previously discharged paper and the newly discharged paper is prevented, and the occurrence of jam is prevented.

According to the sixth aspect of the present invention, by bending the upper portion of the side plate on the side of the paper waist portion toward the outside, even if the position of the discharged paper and the position of the side plate are slightly displaced, Since the leading end of the sheet can be guided to the inside of the side plate by the portion bent toward the outside of the plate, it is possible to prevent the occurrence of jam caused by the sheet colliding with the side plate.

According to the invention of claim 7, the upper portion of the side plate is bent outward, so that even if the position of the discharged paper and the position of the side plate are slightly deviated, they are directed toward the outside of the side plate. Since the front end of the sheet can be guided to the inside of the side plate by the bent portion, the occurrence of jam caused by the sheet colliding with the side plate can be prevented.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the invention described in claims 1 and 5 is shown in FIG.
Or, it demonstrates based on FIG. The same parts as those described with reference to FIG. 9 are represented by the same reference numerals,
The description is omitted (the same applies hereinafter). As shown in FIG. 2, a stencil printing machine 5 including the paper discharge device 4 of this embodiment.
There is. The stencil printing machine 5 is provided with a plate cylinder 6 having a porous cylindrical shape so as to be rotatable. An ink roller 7 and a doctor roller 8 are provided in the lower part of the plate cylinder 6 in close proximity to each other. An ink reservoir 9 is formed in a wedge-shaped space between the ink roller 7 and the doctor roller 8. Further, the ink pipe 1 is provided at the center of rotation of the plate cylinder 6.
0 is set. An ink supply unit 11 is formed by the ink roller 7, the doctor roller 8, the ink reservoir 9 and the ink pipe 10. A stage 12 and a clamper 13 are provided on the circumference of the plate cylinder 6.

A master roll 14 is provided above the plate cylinder 6 in the paper discharge direction (leftward in FIG. 2). The master roll 14 has a roll core 15 and a master 1
6 is rolled up. And the master roll 1
A thermal head 17 is provided above the plate cylinder 6 side of the plate 4, and a platen roller 18 with which the thermal head 17 contacts is provided. These thermal heads 1
7 and the platen roller 18 on the plate cylinder 6 side, a pair of master transport rollers 19 from the thermal head 17 side,
A cutter 20 and a master guide plate 21 are sequentially provided. Then, the master roll 14, the thermal head 17, the platen roller 18, the master transport roller 19, the cutter 20, and the master guide plate 21 form a perforated plate making section 22.

Further, the stencil printing machine 5 is provided with a paper feeding section (not shown) (right side in FIG. 2).
A pair of registration rollers 23 and a sheet detection sensor 24 are sequentially provided in the sheet feeding direction from the sheet feeding unit to the plate cylinder 6. A press roller 25 is provided below the plate cylinder 6 so as to be pressed toward and away from the plate cylinder 6 by being biased upward. Further, in the paper discharge direction of the plate cylinder 6, the peeling claw 2
6. A paper discharge belt 27 is provided. Jump plates 28 are provided on both side edges at the front end of the paper discharge belt 27 in the paper discharge direction.
Are formed. A suction fan (not shown) is provided below the paper discharge belt 27. Then, a paper waist portion 29 is formed by the paper discharge belt 27, the jump plate 28 and the suction fan.

The plate cylinder 6 and the ink supply unit 1
1, the stage 12, the clamper 13, the perforated plate making section 22, the registration roller 23, the press roller 25, and the peeling claw 26 form an image printing section 30.

Further, a paper discharge tray 31 is provided in the paper discharge direction of the paper support portion 29. As shown in FIG. 3, the paper discharge tray 31 is slidably fitted to a paper discharge tray stay 33 provided on the supporting portions 32, 32 of the main body of the stencil printing machine 5. A moving motor 34 is attached to one supporting portion 32 near the discharge tray stay 33.
Is provided. The moving motor 34 includes a screw shaft 3
5 are provided. The screw shaft 35 is screwed with a screw portion 36 formed on one side surface of the paper discharge tray 31.

Further, a tray window 37 is formed in the discharge tray 31 in parallel with the discharge tray stay 33. Below the tray window 37, side plate shafts 38 are rotatably supported in parallel with the paper discharge tray stay 33 on both side surfaces of the paper discharge tray 31.
A moving knob 39 is fixed to one end of the side plate shaft 38 at a position protruding from one side surface of the paper discharge tray 31. A moving gear 40 is fixed to the other end of the side plate shaft 38 below the paper discharge tray 31. The moving gear 40 meshes with the drive gear 41. The drive gear 41 is a drive motor 42.
It is fixed to. The drive motor 42 is fixed to the other side surface of the paper discharge tray 31. Further, the side plate shaft 38 has a right screw formed on one half in the axial direction and a left screw formed on the other half. The right screw and the left screw are respectively screwed with a pair of moving nuts 43 symmetrically with respect to the central axis of the paper discharge tray 31. The upper portions of these moving nuts 43 are loosely fitted in the tray window 37. Then, side plates 44 are fixed to the upper portions of the moving nuts 43 in parallel with each other along the sheet discharge direction. The side plate 44 is formed by applying or forming a low friction member such as Teflon (trade name) on the side surface 45 on the side where the discharged paper 3 comes into contact, and smoothing the side surface 45 to reduce the friction coefficient. It is a thing. Further, as shown in FIG. 4, a shield plate 46 is formed on the moving nut 43 on the drive motor 42 side. Further, the paper output tray 31 is provided with a side plate position detection sensor 4 facing the shield plate 46.
7 are provided. As shown in FIG. 3, a plurality of side plate position detection sensors 47 are provided according to the rated sheet width.

Further, as shown in FIG. 2, an end plate 48 is provided slidably along the paper discharge direction at the front end of the paper discharge tray 31 in the paper discharge direction.

Further, the paper detection sensor 24 and the side plate position detection sensor 47 are connected to a detector 49. The detector 49 and the operation panel 50 provided on the main body of the stencil printing machine 5 are connected to a control unit 51. The control unit 51 includes the moving motor 3
4 and the drive motor 42 are connected.

Although not shown, the stencil printing machine 5 is provided with an image reading section.

In such a structure, when a document is set on the image reading section and a start button (not shown) on the operation panel 50 is pressed, the plate cylinder 6 rotates and the used master 16 is discarded as a master. Plate cylinder 6 by means (not shown)
Peel off and discard. After that, the plate cylinder 6 is attached to the clamper 1.
It will rotate until 3 is almost right above and stop. Then, the clamper 13 separates from the stage 12 and enters the plate supply standby state.

At this time, the image reading unit reads the image of the document and sends the image information to the perforation plate making unit 22. Then, the perforation plate making unit 22 feeds the master 16 out of the master roll 14 by the platen roller 18 and the master conveying roller 19, heat-perforates the plate master 16 with the thermal head 17 based on the image information from the image reading unit, and then the cutter. Two
The master 16 is cut to an appropriate length at 0, and the master 16 is paid out along the master guide plate 21 between the stage 12 and the clamper 13. Then, the tip of the master 16 is held between the stage 12 and the clamper 13. After that, the plate cylinder 6 rotates and the master 16 winds around the plate cylinder 6.

Further, when the sheet width A of the fed sheet 3 is input from the operation panel 50, the side plate position detecting sensor 47 corresponding to the sheet width A is selected. afterwards,
The side plate shaft 38 is rotated by the drive motor 42, and the side plate 44 is moved. And paper width A
Side plate position detection sensor 4 selected according to
When the shield plate 46 shields 7, the drive motor 42 temporarily stops. At this time, the pair of side plates 44 has the paper width A
Are spaced at equal intervals. After that, drive motor 4 again
2 is driven to move the side plate 44. Then, the side plates 44 are arranged at intervals B smaller than the sheet width A.

Further, the paper width A of the paper 3 is set to the operation panel 50.
When inputting the position to feed the paper 3 when inputting from, the moving motor 34 is driven and the paper discharge tray 31 moves according to the position where the paper 3 is discharged. This allows
The paper 3 is always discharged onto the central axis of the paper discharge tray 31.

Further, the end plate 48 is disposed by manual setting by the user or automatic setting using a paper width detection sensor for detecting the paper width A of the paper 3.

After that, the sheets 3 are separated one by one and fed from the sheet feeding section, and fed out between the plate cylinder 6 and the press roller 25 by the registration roller 23 at a timing. When the paper detection sensor 24 detects the paper 3, the press roller 25 operates to press the paper 3 via the master 16 made on the plate cylinder 6. As a result, the ink supplied from the ink supply unit 11 is transferred to the paper 3 through the perforations of the master 16 and the image is printed on the paper 3.

The sheet 3 on which this image is printed is attached to the peeling claw 2.
The sheet is peeled off by 6 and fed to the paper discharge belt 27. Then, the central portion of the paper 3 is discharged by the suction fan to the paper discharge belt 27.
And the side edges of the paper 3 are pushed up by the jump plates 28, so that the paper 3 is printed (upper surface in FIG. 1).
The sheet is bent in a concave shape to the side, and the paper is discharged onto the sheet discharge tray 31.

Sheets 3 discharged onto the discharge tray 31
Touches the side plates 44 on both the left and right sides while warping concavely on the printing surface side. Then, the side plates 44 drop stably with both side edges of the sheet 3 in contact with each other. At this time, the side plate 4 prevents the printing surface of the paper 3 from expanding due to the water content of the ink and warping upward.
It is blocked by 4 and drops while the printing surface warps in a concave shape.

In this way, the side plates 44 are arranged at intervals B narrower than the width A of the sheet, and the friction coefficient of the surface of the side on which the sheets 3 come into contact is reduced, so that the sheet 3 is placed on the side surface of the side plate 44. It can be dropped while being in contact with 45. Therefore, the printing surface of the paper 3 can be dropped while being warped in a concave shape, and the paper 3 can be prevented from moving violently during the fall. Further, it is possible to reduce the resistance when the paper 3 is dropped while being in contact with the side surface 45 of the side plate 44. Therefore, the sheet alignment is improved, and the previously ejected sheet 3 and the newly ejected sheet 3 are prevented from rubbing with each other, so that the show-through and the image stain are prevented. Further, the sheet 3 is stably dropped, the contact between the previously discharged sheet 3 and the newly discharged sheet 3 is prevented, and the occurrence of jam is prevented.

In this embodiment, the side plate 44
As a method of arranging the side plates 4 using a manual set in which the paper width A of the paper 3 is input from the operation panel 50,
Although the method of disposing the side plates 44 has been described, the method of disposing the side plates 44 by using an automatic set that automatically reads the sheet width A of the sheet 3 fed from the sheet feeding section, or by the moving knob 39. There is a method of manually moving and arranging the side plate.

An embodiment of the invention described in claim 2 will be described with reference to FIG. The paper feed unit side of the registration roller 23 (see FIG. 6).
A first roller 52 is rotatably provided on the inside (right side). A thickness detector 53 is provided above the paper feed unit side of the first roller 52. An arm 54 is provided on the thickness detector 53 so as to be rotatable by a predetermined angle.
A second roller 55 is rotatably provided at the tip of the arm 54. However, the first roller 52 and the second roller 55 are provided so that they can come into contact with and separate from each other. The arm 54 is urged counterclockwise (in FIG. 6) by urging means (not shown). Then, the first roller 52, the thickness detector 53, the arm 54,
The second roller 55 forms a thickness detecting portion 56 which is a thickness detecting means. The thickness detector 56 is connected to the detector 49. Further, the drive motor 42 is
It operates as a side plate disposing means. A variable resistor (not shown) is incorporated in the thickness detector 53. This variable resistor is formed so that its resistance value changes in accordance with the rotation angle of the arm 54.

In such a structure, when the sheet width A of the sheet 3 to be fed is input from the operation panel 50, the side plate position detection sensor 47 corresponding to the sheet width A and the drive motor 42 cause the side plate 44. Are arranged at intervals equal to the paper width A. After that, the paper 3 is fed from the paper feed unit to the plate cylinder 6. At this time, the paper 3 is the first roller 5
It passes between 2 and the second roller 55. At that time, the second roller 55 is pushed upward according to the thickness of the sheet 3. The arm 54 rotates upward in accordance with the second roller 55, and the resistance value of the variable resistor of the thickness detector 53 changes. The control unit 51 determines the thickness of the sheet 3 based on this resistance value. When the thickness is smaller than the predetermined thickness, the drive motor 42 is driven again to arrange the side plates 44 at intervals B narrower than the sheet width A. When the thickness of the paper 3 is thicker than a predetermined thickness, the drive motor 4
2 does not drive, and the side plates 44 are arranged at intervals substantially equal to the sheet width A.

As described above, the thickness detecting section 56 is provided, and based on the thickness of the sheet 3 detected by the thickness detecting section 56, when the sheet 3 is thin and the sheet itself is weak, the sheet width A
The side plates 44 are arranged at a narrower interval B, and the paper 3
When the sheet is thick and the sheet itself is stiff, the side plates 44 are arranged at intervals substantially equal to the sheet width A, so that even the sheet 3 that is thick and the sheet itself is stiff can contact the side surface 45 of the side plate 44. It is possible to prevent the resistance when dropping in the state where it is made too large. Therefore, the sheet 3 stably drops regardless of whether it is thin or thick. Therefore, the contact between the previously discharged sheet 3 and the newly discharged sheet 3 is prevented, and the occurrence of jam is prevented.

In this embodiment, when the thickness of the sheet 3 is large, the side plates 44 are arranged at intervals equal to the sheet width A. However, the thickness of the sheet 3 detected by the thickness detecting section 56 is not limited to the above. When the sheet thickness is large, the drive motor 42 may be driven slightly to arrange the side plates 44 at intervals slightly smaller than the sheet width A.

Further, the drive motor 42, which is a side plate arranging means, has the side plate 44 at an arbitrary interval between the interval B narrower than the sheet width A and the interval substantially equal to the sheet width A.
Shall be provided. Then, based on the thickness of the sheet 3 detected by the thickness detection unit 56, when the sheet 3 is thin and the sheet itself is weak, the side plates 44 are arranged at intervals B narrower than the sheet width A, and the sheet 3 When the sheet 3 is thick and the sheet itself is strong, the side plates 44 are arranged at intervals substantially equal to the sheet width A, and when the sheet 3 is neither thick nor thin and the sheet itself is neither strong nor weak, the sheet 3 The side plates 44 are arranged at an arbitrary interval between the interval B narrower than the sheet width A and the interval substantially equal to the sheet width A depending on the thickness of the sheet. As a result, it is possible to prevent the resistance of the sheet itself, which may be strong or weak, from dropping excessively when the sheet 3 is dropped while being in contact with the side surface of the side plate 44. it can. Therefore, any paper 3 from the strong one to the weak one is stably dropped. Therefore, the contact between the previously discharged sheet 3 and the newly discharged sheet 3 is prevented, and the occurrence of jam is prevented.

Further, it is assumed that the control section 51 operates as a size detecting means. The size detecting unit records the image information of the original read by the image reading unit, compares the ratio of the ink transfer portion of the paper 3 with the ink transfer portion of the paper 3, and compares The size of the portion to which the ink is transferred is detected. According to this, the control unit 51 detects the size of the portion of the paper 3 to which the ink is transferred, based on the image information of the document read by the image reading unit. When the portion of the paper 3 to which the ink is transferred is small, the side plate 44 is moved at the intervals arranged based on the paper width A of the paper 3 or the paper width A and the thickness of the paper 3. Arrange.
However, when the portion of the paper 3 to which the ink is transferred is large, the drive motor 42 is driven to dispose the paper 3 based on the paper width A of the paper 3 or based on the paper width A and the thickness of the paper 3. Side plates 44 at intervals smaller than the intervals
To arrange. In this manner, the space between the side plates 44 is narrowed according to the size of the portion of the paper 3 to which the ink is transferred detected by the controller 51, and the paper 3 is in contact with the side surface 45 of the side plate 44. By dropping the sheet 3, it is possible to drop the sheet 3 while the printing surface of the sheet 3 is warped in a concave shape, and it is possible to prevent the sheet 3 from being violent during the drop. Therefore, even when the portion of the paper 3 to which the ink is transferred becomes large and the stiffness of the paper 3 becomes weak, the paper alignment is improved, and the paper 3 previously discharged and the paper 3 newly discharged are Is prevented, and the occurrence of show-through and image stains is prevented.

An embodiment of the invention described in claim 6 will be described with reference to FIG. On the discharge tray 31, the moving nut 4
A side plate 57 fixed to the No. 3 is provided.
On the upper portion of the side plate 57 on the side of the sheet waist portion 29, an edge bend portion 58 that is inclined toward the side where the sheet 3 does not contact is formed. With such a configuration, even if the central axis of the discharged sheet 3 and the central axis of the sheet discharge tray 31 are slightly deviated from each other, the sheet 3 is guided along the edge portion 58. The sheet 3 does not collide with the side plate 57, and the occurrence of jam is prevented.

An embodiment of the invention described in claim 7 will be described with reference to FIG. On the discharge tray 31, the moving nut 4
3 is provided with a side plate 59 fixed thereto.
On the upper portion of the side plate 59, an edge bend portion 60 is formed that is inclined toward the side where the sheet 3 does not come into contact. According to such a configuration, even if the central axis of the discharged sheet 3 and the central axis of the sheet discharge tray 31 are slightly deviated from each other, the sheet 3 is guided along the edge portion 60, and therefore the sheet 3 is guided. Does not collide with the side plate 59, and jamming is prevented.

[0047]

According to the first aspect of the present invention, the pair of side plates are provided at intervals narrower than the width of the sheet, and both side edges of the sheet are dropped while being brought into contact with the side surfaces of the side plate. Since the printing surface of the paper can be dropped while curving in a concave shape, it is possible to prevent the paper from moving violently during the fall, so that the paper alignment can be improved,
In addition, it is possible to prevent rubbing between the previously ejected paper and the newly ejected paper, and it is possible to prevent occurrence of show-through and image stains.

According to a second aspect of the invention, in addition to the effect of the first aspect of the invention, the sheet itself is thin by the side plate disposing means based on the thickness of the sheet detected by the thickness detecting means. By arranging the pair of side plates at a distance narrower than the width of the paper when the stiffness of the paper is weak, and by arranging the pair of side plates at a distance almost equal to the width of the paper when the paper is thick and the stiffness of the paper itself is strong, Even if the paper is thick and the paper itself is stiff, it is possible to prevent excessive resistance when dropping it while it is in contact with the side surface of the side plate. Therefore, it is possible to prevent contact between the previously discharged sheet and the newly discharged sheet, and it is possible to prevent jamming.

According to a third aspect of the invention, in addition to the effect of the first aspect of the invention, the sheet itself is thinned by the side plate disposing means based on the thickness of the sheet detected by the thickness detecting means. When the stiffness of the paper is weak, a pair of side plates are arranged at intervals narrower than the width of the paper, and when the paper is thick and the stiffness of the paper itself is strong, the pair of side plates are arranged at intervals substantially equal to the width of the paper. When the paper is neither thick nor thin and the paper itself is neither stiff nor weak, a pair of sides can be placed at an arbitrary interval between the space narrower than the width of the paper and the space approximately equal to the width of the paper depending on the thickness of the paper. By arranging the plates, it is possible to prevent the resistance of the paper itself from dropping too much when it is in contact with the side of the side plate, regardless of whether the paper is strong or weak. To prevent Since it is possible to stabilize and drop the paper, it is possible to prevent the contact between the previously discharged paper and the newly discharged paper and prevent the occurrence of a jam. it can.

According to a fourth aspect of the present invention, in addition to the effects of the first, second or third aspect of the present invention, based on the size of the portion to which the ink is transferred on the paper detected by the size detecting means. As the portion of the paper on which the ink is transferred by the side plate arranging means becomes larger, the interval between the pair of side plates becomes narrower, and both side edges of the paper are dropped in contact with the side surfaces of the side plates. By
It can be dropped while curving the printing surface of the paper in a concave shape, and it is possible to prevent the paper from moving violently while falling, so that the ink transfer area on the paper becomes large and the paper becomes less stiff. Even when the paper is ejected, it is possible to improve the paper alignment and prevent rubbing between the previously ejected paper and the newly ejected paper, which prevents the occurrence of show-through and image stains. Can be prevented.

The invention according to claim 5 is the invention as claimed in claims 1, 2, and 3.
Alternatively, in addition to the effect of the invention described in 4, the friction coefficient of the side surface of the side plate with which the sheet comes into contact is reduced, so that the resistance when dropping both side edge portions of the sheet with the side surface of the side plate abutted. Since the paper can be reduced, the paper can be stably dropped, and the contact between the previously discharged paper and the newly discharged paper can be prevented, and the occurrence of jams can be prevented. can do.

The invention according to claim 6 is the same as claims 1, 2 and
In addition to the effects of the invention described in 3, 4, or 5, the position of the discharged paper and the position of the side plate are slightly displaced by bending the upper part of the side plate on the paper waist portion side toward the outside. Also, since the leading end of the sheet can be guided to the inside of the side plate at the portion bent toward the outside of the side plate, it is possible to prevent the occurrence of jam caused by the sheet colliding with the side plate.

The invention according to claim 7 is the same as claim 1,
In addition to the effect of the invention described in 3, 4, or 5, by bending the upper portion of the side plate outward, even if the position of the ejected paper and the position of the side plate are slightly displaced, the side plate is placed outside the side plate. Since the leading end of the sheet can be guided to the inside of the side plate at the bent portion, it is possible to prevent the occurrence of jam caused by the sheet colliding with the side plate.

[Brief description of drawings]

FIG. 1 is a side view showing a paper discharge tray of an embodiment of the invention described in claims 1 and 5. FIG.

FIG. 2 is a vertical sectional front view showing a stencil printing apparatus.

FIG. 3 is a partially cutaway plan view showing a paper discharge tray.

FIG. 4 is a vertical sectional front view thereof.

FIG. 5 is a block diagram of a paper discharge device.

FIG. 6 is a vertical sectional front view of a stencil printing machine showing an embodiment of the invention as set forth in claim 2;

FIG. 7 shows a side plate of an embodiment of the invention as set forth in claim 6, (a) is a plan view, (b) is a front view, and (c) is a side view.

FIG. 8 shows a side plate of an embodiment of the invention as set forth in claim 7, (a) is a plan view, (b) is a front view, and (c) is a side view.

FIG. 9 is a side view showing a conventional paper discharge tray.

[Explanation of symbols]

 3 paper 29 paper waist part 30 image printing part 31 paper ejection tray 42 drive motor 44 side plate 45 side surface of the side plate with which the paper comes into contact 51 size detection means 56 thickness detection means 57 side plate 59 side plate

Claims (7)

[Claims] 1. An image printing unit for printing an image by transferring ink to a sheet, a sheet supporting unit for supporting a sheet provided in a sheet discharging direction of the image printing unit, and a discharging unit for the sheet supporting unit. A paper ejection device of a stencil printing apparatus, comprising: a paper ejection tray provided in a paper direction; and a pair of side plates arranged on the paper ejection tray at intervals smaller than a width of paper. 2. Thickness detecting means for detecting the thickness of a sheet,
A side plate arrangement in which a pair of side plates is arranged at either one of an interval narrower than the width of the sheet and an interval substantially equal to the width of the sheet based on the thickness of the sheet detected by the thickness detecting means. The sheet discharging device of the stencil printing apparatus according to claim 1, further comprising: 3. Thickness detecting means for detecting the thickness of a sheet,
A side plate arrangement in which a pair of side plates is arranged at an arbitrary interval between an interval narrower than the width of the sheet and an interval substantially equal to the width of the sheet based on the thickness of the sheet detected by the thickness detecting means. The sheet discharging device of the stencil printing apparatus according to claim 1, further comprising: 4. A size detecting means for detecting a size of an ink transferred portion on a sheet, and a size of the ink transferred portion on the paper detected by the size detecting means. 4. A sheet discharging device for a stencil printing apparatus according to claim 1, further comprising side plate disposing means for narrowing a space between the pair of side plates. 5. The friction coefficient of the side surfaces of the pair of side plates with which the sheets are in contact is reduced.
A paper discharge device of the stencil printing machine according to 2, 3, or 4. 6. The pair of side plates is bent outward so that the upper portions of the side portions of the sheet on which the paper is attached are bent.
A sheet discharge device of the stencil printing machine according to 2, 3, 4 or 5. 7. The sheet discharging device of the stencil printing apparatus according to claim 1, wherein the upper portions of the pair of side plates are bent outward.