JP2000103155A - Delivery device of stencil printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost without spoiling the reliability of a delivery device. SOLUTION: The delivery device is provided with a belt carrying section driven by the speed faster than that of a plate cylinder 1, a pawl 9 positioned in the vicinity of a plate cylinder 1 on the downstream side of a pressing section A in the revolving direction of the plate cylinder 1 and releasing a base 30 from the plate cylinder 1 by bringing the end of the paper 30 passing through the pressing section 30 into contact with the pawl, a suction machine 14, flow paths 16a and 16 positioned on the air suction side of the suction machine 14 and applying the suction action by the suction machine 14 to a belt carrying section, flow paths 20 and 17 positioned on the exhaust side of the suction machine 14 wherein air suction exhausted by the suction machine 14 is passed through and an air plenum 17a positioned in the vicinity of the pawl 9 of the flow path 17, and blowing air in the flow path 17 toward between the plate cylinder 1 and the paper 30 passed through the pressing section A. Both of the function of releasing the paper 30 from the plate cylinder 1 and the function of bringing the paper 30 into close contact with a belt 13 of the belt carrying section are realized by one suction machine 14, and the paper 30 is released from the plate cylinder 1 in a good and stabilized manner, carrying the paper to the downstream side and the number of fans is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper discharge device for a stencil printing machine, and more particularly to a paper discharge device using an air suction device.

[0002]

2. Description of the Related Art Generally, a stencil printing machine is provided with a plate cylinder having a perforation for winding a stencil sheet on an outer peripheral surface and leaching ink inside the perimeter surface. Presses the printing paper at a predetermined pressing position (hereinafter referred to as a pressing contact portion), thereby transferring the internal ink to the printing paper via the stencil paper and forming an image corresponding to the stencil paper on the printing paper. The printing paper is conveyed to a downstream paper discharge path.

[0003] In such a stencil printing machine, the printing paper passes through the pressing contact portion so that the printing paper remains on the plate cylinder even after the printing paper passes through the pressing contact portion due to the adhesive action of the ink oozing out of the stencil printing paper to the printing paper. A conveyance failure has occurred in which the printing paper cannot be reliably guided to the paper discharge path with the sheet stuck.

In order to prevent such a problem, a separation claw that forcibly peels off the printing paper stuck on the plate cylinder from the plate cylinder and guides the printing paper to a paper discharge path, a printing stuck on the plate cylinder, A method in which the paper is peeled off from the plate cylinder using the air jet of the blower fan, or the air jet of the blower fan blows out from the tip of the separation claw to print the paper with the separation claw while promoting the separation of the printing paper from the plate cylinder. There are known methods for preventing the image surface from being stained. In general, both the separation claw and the blower fan are used to enhance the releasability of the printing paper.

On the other hand, as a paper transport mechanism disposed in the paper discharge path, a surface (rear surface) opposite to the surface on which the image of the printing paper is formed is used as a transport belt by utilizing the suction force of a suction fan. A mechanism for sucking and transporting the sheet downstream is often used.

[0006]

As described above, in the current stencil printing machine, as a paper discharging device, a stencil fan for peeling off the printing paper stuck on the plate cylinder from the plate cylinder and a paper conveying mechanism are used. In general, two suction fans are used. However, since the fans themselves are expensive, there is a problem that the cost of the printing machine is increased.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it is an object of the present invention to reduce the cost by reducing the number of fans without reducing the reliability of the apparatus. It is intended to provide a device.

[0008]

According to the present invention, a stencil printing machine according to the present invention has a paper stencil printing machine, wherein a stencil sheet is wound around an outer peripheral surface thereof, and the stencil sheet presses a printing sheet at a predetermined pressing position. From the plate cylinder that conveys the printing paper downstream while transferring the image corresponding to the stencil sheet to the printing paper, the printing paper on which the image has been transferred through the above-mentioned predetermined pressing position is peeled off and a predetermined discharging path A paper discharge device for a stencil printing machine that discharges paper through a paper discharge belt transport unit that is disposed in the predetermined paper discharge path, is driven at a speed higher than the peripheral speed of the plate cylinder, and has air permeability; A separation claw that is arranged near the plate cylinder on the downstream side in the rotation direction of the plate cylinder from the predetermined pressing position, and peels off the printing paper from the plate cylinder by contacting the leading end of the printing paper that has passed the predetermined pressing position. And one air suction device for sucking air And an intake-side air flow path that is disposed on the intake side of the air suction device and applies the suction effect of the air suction device to the discharge belt conveyance unit, and is disposed on the exhaust side of the air suction device and is sucked by the air suction device. An exhaust-side air flow path through which the exhausted air passes, and an exhaust-side air path provided in the exhaust-side air flow path and located near the separation claw and directed between the plate cylinder and the printing paper that has passed the predetermined pressing position. And an outlet for blowing air in the air flow path.

According to the paper discharge device of the stencil printing machine according to the present invention, when one air suction device is driven, the suction action of the air suction device causes the air to flow through the air passage on the intake side. Is applied to the paper discharge belt conveying section provided with the air suction device, and the air sucked and exhausted by the air suction device is blown out from the air outlet located near the separation claw via the exhaust side air flow path. The air blown out from the outlet passes through a predetermined pressing position and travels between the printing paper on which the image corresponding to the stencil sheet has been transferred and the plate cylinder. ) Rises from the plate cylinder in response to this air.

Here, the behavior of the subsequent printing paper differs depending on the printing rate of the print image following the margin. For example, when the printing rate of the print image following the margin is relatively low, the printing paper blows out from the outlet. The printing paper is peeled off from the plate cylinder by the air that has flowed, while if the printing rate of the print image following the margin is relatively high, the separation of the printing paper from the plate cylinder is promoted,
The printing paper contacts the separation claw while receiving the air blown out from the outlet, and is peeled off from the plate cylinder by the separation claw.

Regardless of the printing ratio, the portion of the printing paper that has been peeled off from the plate cylinder is brought into close contact with the paper discharge belt by the suction action through the paper discharge belt transport section. Since the transporting unit is driven at a speed higher than the peripheral speed of the plate cylinder, the printing paper is transported while being pulled downstream while the back surface of the printing paper and the discharge belt slide.

[0012] As the printing paper is conveyed downstream, the air permeability of the discharge belt conveyance section is gradually obstructed by the printing paper, and the amount of air blown from the outlet decreases.
Since the air permeability is not completely eliminated, the blowing amount for promoting the separation of the printing paper from the plate cylinder is secured. Further, when the printing paper is conveyed downstream and the air permeability of the paper discharge belt conveyance unit is completely lost, the blowing of air from the air outlet is stopped, but at this time, the portion of the printing paper that has passed the predetermined pressing position is passed. Has already been conveyed downstream in a stable state while being completely in close contact with the discharge belt.

As described above, since both the function of peeling the printing paper from the plate cylinder and the function of bringing the printing paper into close contact with the discharge belt of the discharge belt transport unit are realized by one air suction device, the printing is performed. The sheet is satisfactorily and stably peeled off from the plate cylinder and transported downstream, and the number of fans is reduced.

Here, as the blow-out port, for example, a structure is employed which is located near the downstream side in the rotation direction of the plate cylinder from the separation claw.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a paper discharge device for a stencil printing machine according to the present invention will be described below with reference to the accompanying drawings. In each of the drawings, the same elements are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 is a front view showing a paper discharging device of a stencil printing machine according to an embodiment of the present invention together with its peripheral portion, and FIG.
FIG. 3 is a partially cutaway plan view showing a discharge belt transporting section 50, a suction fan 14, and first and second air ducts 25 and 20 constituting a sheet discharge device. FIG. 3
3 is a cross-sectional plan view showing the air ducts 20 and 17, the air outlet 17a, and the separation claw 9. FIG.

In FIG. 1, a plate cylinder 1 made of a porous material in a cylindrical shape has a central axis 1a rotatably supported by a frame 3 of a stencil printing machine, and a plate cylinder driving mechanism (not shown). Is rotated clockwise in the figure. This plate cylinder 1
A stencil sheet 2 having a perforation corresponding to a print image is wound around the outer peripheral surface thereof, and an ink supply mechanism and an ink pushing mechanism (not shown) are provided therein.

An impression cylinder 4 is arranged to face the plate cylinder 1. The impression cylinder 4 has a center axis 5 rotatably supported, and can selectively press the plate cylinder 1 by a spring device (not shown). It is configured to rotate with the plate cylinder 1 while pressing the plate 30 against the plate cylinder 1. Thereby, the plate cylinder 1 and the impression cylinder 4
A pressing contact portion (predetermined pressing position; also referred to as a nip portion) A having a predetermined width for narrowing the printing paper 30 is formed between
When the printing paper 30 passes through the pressing contact portion A, the plate cylinder 1
By the action of the ink supply mechanism and the ink push-out mechanism inside, the ink inside the plate cylinder 1 oozes out to the outer peripheral side of the stencil sheet 2 through the holes of the plate cylinder 1 and the perforations of the stencil sheet 2, and the printing paper 30 The image corresponding to the perforation of the stencil sheet 2 is transferred.

A pair of registration rollers 6 and a pinch roller 7 and a paper guide 8 are disposed on the transport path upstream of the pressing contact portion A in the paper transport direction. The registration roller 6 and the pinch roller 7 convey the printing paper 30 toward the pressing contact portion A, and the paper guide 8 regulates the conveyance path.

A separation claw 9 is arranged near the plate cylinder 1 downstream of the press contact portion A in the rotation direction of the plate cylinder 1. The separation claw 9 is supported by a support shaft 10 (see FIG. 3) laid over the frame 3 and has a sharp tip 9a formed on the outer peripheral surface of the plate cylinder 1. It is arranged so as to be very close to it. The leading end 9a of the separation claw 9 catches the leading end (front edge) of the printing paper 30 stuck to the plate cylinder 1 by the adhesive action of the ink even after passing through the pressing contact portion A, and Is peeled off from the plate cylinder 1 as the plate cylinder 1 rotates.

A discharge belt transport section 50 is disposed on the discharge path downstream of the pressing contact section A in the sheet transport direction. The delivery belt transport unit 50 includes a drive shaft 22a and a driven shaft 22b that are parallel to the center axis 1a of the plate cylinder 1 and rotatably supported.
, A drive pulley 12 fixed to the drive shaft 22a, a driven pulley 11 fixed to the driven shaft 22b, and an endless flat belt ( And a plurality of (four in the present embodiment) belt conveyance units including a discharge belt 13 in the axial extension direction (axial direction; the direction perpendicular to the paper surface of FIG. 1). That is, as shown in FIG. 2, four drive pulleys 12 and four driven pulleys 11 are fixed to the drive shaft 22a and the driven shaft 22b, respectively. Endless flat belts 13 are respectively stretched.

These belt transport sections are spaced apart from each other at a predetermined interval (equal interval) in the axial direction. For this reason, the discharge belt conveyance unit 50 has air permeability due to the space defined between the belt conveyance units.

A rotational driving force is applied to the drive shaft 22a by a discharge belt driving mechanism (not shown), and the endless flat belt 13 is driven at a speed higher than the peripheral speed of the plate cylinder 1. . The endless flat belt 13 is made of a material having a relatively high coefficient of friction, such as rubber. Note that a round belt, a V-belt, or the like may be used instead of the endless flat belt.

As shown in FIGS. 1 and 2, a suction fan (air suction device) 14 such as a DC fan is disposed below the discharge belt conveying section 50. This suction fan 1
4 is rotatably accommodated in a fan housing 15 fixed to the frame 3. As shown in FIG. 1, a vent 15a communicating with the outside of the fan housing 15 is opened at an upper portion of the fan housing 15, and the upper surface of the fan housing 15 is suctioned so as to surround the vent 15a. Box 16 is fixed. In the suction box 16, portions corresponding to (opposed to) the space defined between the belt conveyance units extend to near the upper side of the endless flat belt 13, and as shown in FIG. Each of the extending portions has a suction hole 16a at an upper portion thereof.

These suction holes 16a, suction box 1
6. Due to the vent 15a and the upper side of the fan housing 15,
The suction operation by the suction fan 14 is performed by the discharge belt transport unit 50.
And a surface opposite to the surface on which the image of the printing paper 30 is formed on the plurality of endless flat belts 13 (hereinafter simply referred to as a back surface, and a surface opposite to the back surface). The surface is called a surface, and is conveyed by suction.

As shown in FIGS. 1 and 2, a wind outlet 14a for communicating the inside of the fan housing 15 with the outside is formed on the side of the fan housing 15. As shown in FIG. 2, a first air duct 25 is connected to the wind outlet 14a.
Air duct 2 through communication hole 3a
Connected to 0. This second air duct 20 is shown in FIG.
As shown in FIG. 3, it extends upward and is connected to the third air duct 17 through a communication hole 3b opened in the frame 3 as shown in FIG.

The lower side of the fan housing 15, the air outlet 14a, the first air duct 25, the communication hole 3a, the second
The air duct 20, the communication hole 3b, and the third air duct 17 form an exhaust-side air passage through which the air sucked and exhausted by the suction fan 14 passes.

An air outlet (air outlet) 17a is opened at the end of the third air duct 17, as shown in FIGS. This air outlet 17a is
As shown in FIG. 1, the printing paper 30 is disposed so as to face substantially the center in the width direction of the printing paper 30 near the downstream side in the rotation direction of the plate cylinder 1 from the separation claw 9 (see FIG. 3). Air is blown from behind the separation claw 9 between the plate cylinder 1 and the printing paper 30 that has passed through the pressing contact portion A.

As shown in FIGS. 1 and 2, a pair of print papers 30 conveyed by the belt transport unit are provided on both sides of the upper side of the discharge belt transport unit 50 on the downstream side of the belt transport unit. The paper discharge wings 21 are arranged (only the paper discharge wing 21 on one side is shown in FIG. 2), and the printing paper 3 which has flew by the paper discharge wings 21 is provided.
A paper discharge tray 23 for stocking 0s is provided outside the machine.

The above-described paper discharge belt transport section 50, separation claw 9, suction fan 14, and air flow paths 3a, 3b, 14a, 1
The paper discharge device of the stencil printing machine is constituted by 5, 15a, 16, 16a, 17, 20, 25 and the air outlet 17a.

Next, the operation of the paper discharge device of the stencil printing machine thus configured will be described with reference to FIG.
First, prior to printing, the plate cylinder 1 is driven to rotate by the plate cylinder driving mechanism, the belt transport section of the discharge belt transport section 50 is driven by the discharge belt drive mechanism, and a predetermined voltage is applied to the suction fan 14. The suction fan 14 is rotationally driven by the application.

By the rotation of the suction fan 14, the air above the discharge belt conveyance unit 50 is moved through the suction holes 16a, the suction boxes 16, and the ventilation holes 15a between the belt conveyance units, so that the suction fan 14 in the fan housing 15 is formed. The air that has been sucked in and exhausted (exhausted) by the suction fan 14 is supplied to the fan housing 15, the air outlet 14 a, and the first air duct 2.
5, vent 3a, second air duct 20, vent 3
b, the air is blown out along the outer peripheral surface of the plate cylinder 1 through the third air duct 17 and the air outlet 17a. The flow of air along the outer peripheral surface of the plate cylinder 1 is directed between the plate cylinder 1 and the printing paper 30 that has passed through the pressing contact portion A.

On the other hand, the printing paper 30 is transported downstream in the paper transport direction by the registration rollers 6 and the pinch rollers 7 while the transport path is regulated by the paper guide 8, and presses between the rotating plate cylinder 1 and the impression cylinder 4. The contact part A is reached. The printing paper 30 is pressed by the plate cylinder 1 and the impression cylinder 4 at the pressing contact portion A, so that ink is transferred to the surface thereof and an image corresponding to the stencil sheet 2 is formed. As the impression cylinder 4 rotates, it is transported downstream in the paper transport direction. As described above, since the ink has a sticking action, the printing paper 30 sticks to the plate cylinder 1 even after passing through the pressing contact portion A.

Since there is a margin at the leading end of the printing paper 30 and, of course, ink is not transferred to this margin, the leading end of the printing paper 30 receives the air blown out from the air outlet 17a. As shown in FIG. 1, the front end portion rises from the plate cylinder 1.

The subsequent behavior of the printing paper 30 depends on the printing ratio of the print image following the margin, and
First, the case where the printing rate of the print image following the margin is relatively low will be described with reference to FIGS.

In this case, as shown in FIG.
With the further rotation of the printing paper 30, the leading end of the printing paper 30 further rises by receiving the air blown out from the air outlet 17a, and before the leading end of the printing paper 30 reaches the separation claw 9a, the leading end of the printing paper 30 Since the subsequent sheet portion also has a low printing rate, the sheet portion is peeled off from the plate cylinder 1 by receiving the air blown out from the air outlet 17a.

When the printing drum 30 is further rotated and the printing paper 30 is further transported downstream, the leading end of the printing paper 30 becomes a negative pressure due to suction at the suction hole 16a of the suction box 16 and its vicinity, and the air The air blown out from the air outlet 17a and the weight of the printing paper 30 contact the endless flat belt 13 as shown in FIG. With the rotation of the plate cylinder 1, the aperture ratio of the suction holes 16a gradually decreases because the number of paper portions of the printing paper 30 that cover the suction holes 16a increases,
As a result, the amount of air blown out from the air outlet 17a gradually decreases. However, as shown in FIG. 5, in the initial state of contact of the leading end of the printing paper 30 with the endless flat belt 13, printing is not performed. The air volume from the air outlet 17a for peeling the paper 30 from the plate cylinder 1 against the adhesive action of the ink is still sufficiently maintained.

When the printing drum 30 is further rotated and the printing paper 30 is transported further downstream, the paper portion above the suction holes 16a of the printing paper 30 is shown in FIG. In this way, it is completely adhered to the endless flat belt 13. Here, as described above, the endless flat belt 13 is
Since the printing paper 30 is driven at a speed higher than the peripheral speed of the printing drum 1, the printing paper 30 is conveyed while being pulled downstream while the back surface of the printing paper 30 and the endless flat belt 13 slide.

At this time, the opening ratio of the suction hole 16a is approximately 50%.
(See FIG. 6), but since the suction hole 16a is not completely closed, the amount of air blown out from the air outlet 17a to promote the separation of the printing paper 30 from the plate cylinder 1 Is secured.

When the printing cylinder 30 is further conveyed further downstream by rotating the plate cylinder 1, as shown in FIG.
6a is completely closed by the printing paper 30, and the blowing of air from the air outlet 17a is stopped. At this time, the paper portion that has passed through the pressing contact portion A of the printing paper 30 is already Since it is transported in a stable state while being closely contacted with and pulled downstream, there is no problem even if there is no air blowing from the air blowing port 17a.

Next, the case where the printing rate of the print image following the margin is relatively high will be described with reference to FIGS. In this case, as shown in FIG. 8, with the further rotation of the plate cylinder 1 following FIG. 1, the leading end of the printing paper 30 further rises by receiving the air blown out from the air outlet 17a. Here, since the printing rate of the print image following the margin is relatively high, the degree of floating is smaller than that in the case of FIG. 4 where the printing rate is relatively low. When the leading end of the printing paper 30 rises, a gap is formed in which the leading end 9 a of the separation claw 9 can enter between the plate cylinder 1 and the leading end of the printing paper 30.

When the printing cylinder 30 is further rotated and the printing paper 30 is further transported downstream, the leading end of the printing paper 30 is separated from the printing cylinder 1 by the air blown out from the air outlet 17a. As shown in FIG. 9, the plate cylinder 1 comes into contact with the separation claw 9 and is
Peeled off.

When the printing cylinder 30 is further rotated and the printing paper 30 is further transported downstream, the leading end of the printing paper 30 becomes a negative pressure due to suction in the suction hole 16a of the suction box 16 and its vicinity, and the air Due to the air blown out from the air outlet 17a and the weight of the printing paper 30, the printing paper 30 hangs downward and travels toward the paper discharge belt transport unit 50 as shown in FIG. 10.

At this point, the printing paper 30 is
As described above, when the printing paper 30 is peeled from the plate cylinder 1 by only the separation claw 9 because of the separation promoting action of the air blown out from the air outlet 17a as described above. The contact pressure of the printing paper 30 against the separation claw 9 is smaller than that of the printing paper 30, and the image formed on the printing paper 30 is prevented from being damaged.

When the printing drum 30 is further rotated and the printing paper 30 is transported further downstream, as shown in FIG. 11, the printing paper 30 separates from the separation claw 9 and the leading end thereof is endless. It contacts the flat belt 13. In this state, as in the case of FIG. 5, since the leading end of the printing paper 30 only partially covers the suction hole 16a, the air volume from the air outlet 17a is almost the same as the initial state shown in FIG. does not change. For this reason, the air blown out from the air outlet 17a promotes the separation of the printing paper 30 from the plate cylinder 1.

Then, with further rotation of the plate cylinder 1,
The printing paper 30 is conveyed while being pulled downstream while the back surface of the printing paper 30 and the endless flat belt 13 slide, and thereafter, the operation is the same as that described with reference to FIGS.

As described above, in the present embodiment, both the function of peeling the printing paper 30 from the plate cylinder 1 and the function of bringing the printing paper 30 into close contact with the endless flat belt 13 of the discharge belt transport unit 50 are provided by one unit. , The printing paper 30 is peeled off from the plate cylinder 1 stably and conveyed downstream, and the number of fans is reduced.

When the endless flat belt 13 is driven at a speed lower than the peripheral speed of the plate cylinder 1, the printing paper 30 is not pulled between the pressing contact portion A and the discharge belt conveying portion 50. For this reason, when the printing rate of the print image following the blank portion is relatively low, the paper portion that has passed through the pressing contact portion A of the printing paper 30 is stuck to the vicinity of the pressing contact portion A of the plate cylinder 1. Therefore, a large amount of ink is transferred to the printing paper 30 and the image bleeds. On the other hand, when the printing rate of the printing image following the margin is relatively high, the printing paper 30 , And the image formed on the printing paper 30 is damaged.

However, in the present embodiment, the endless flat belt 13 is driven at a speed higher than the peripheral speed of the plate cylinder 1, so that the printing paper 30 is peeled off from the plate cylinder 1 in a stable manner, and the printing paper 30 is downstream. It is designed to be transported.

As described above, the present invention has been specifically described based on the embodiments. However, the present invention is not limited to the above embodiments. Although a space is defined between them, the discharge belt conveying section 50 is provided with air permeability. However, separately from this configuration or in combination with this configuration, the endless flat belt 13 has a vent hole. May be provided, so that the discharge belt conveying unit 50 has air permeability.

The inside of the separation claw 9 communicates with the third air duct 17, and the leading end 9 a of the separation claw 9 is attached to the plate cylinder 1.
Needless to say, an air outlet (air nozzle) for blowing air toward the printing paper 30 passing through the pressing contact portion A may be provided.

Further, another air outlet may be provided below the separation claw 9 to blow air. With such a configuration, the performance of separating the printing paper 30 from the plate cylinder 1 is further improved, and the quality of the printed image is further prevented from deteriorating due to the contact of the printing paper 30 with the separation claw 9. Will be done.

Furthermore, in the above embodiment, an example of application to a single-sided printing press is described, but the present invention is also applicable to a double-sided printing press in which the impression cylinder 4 is replaced with a plate cylinder. In this case, the separation claw 9 is also provided for the second plate cylinder used in place of the impression cylinder 4, and the exhaust-side air flow path for the second plate cylinder is provided to the fan housing 15. Preferably, an air outlet is provided in the exhaust-side air flow path for blowing air toward between the second plate cylinder and the printing paper 30 that has passed through the pressing contact portion A.

[0054]

According to the present invention, there is provided a paper discharge device for a stencil printing machine.
Both the function of peeling the printing paper from the plate cylinder and the function of bringing the printing paper into close contact with the discharge belt of the discharge belt transport section
This is realized by a single air suction device. Therefore, the printing paper can be peeled off from the plate cylinder with good stability and can be transported downstream, and the number of fans can be reduced. As a result, the cost can be significantly reduced without impairing the reliability of the device.

[Brief description of the drawings]

FIG. 1 is a front view showing a sheet discharging device of a stencil printing machine according to an embodiment of the present invention, together with a peripheral portion thereof.

FIG. 2 is a partially cutaway plan view illustrating a discharge belt transport unit, a suction fan, and first and second air ducts that constitute the discharge device.

FIG. 3 is a cross-sectional plan view showing second and third air ducts, an air outlet, and a separation claw that constitute the sheet discharging device.

FIG. 4 is an explanatory diagram showing the behavior of the printing paper accompanying the operation of the paper ejection device when the printing rate of the print image following the margin is relatively low.

FIG. 5 is an explanatory diagram showing the behavior of the printing paper associated with the operation of the paper ejection device following FIG. 4;

FIG. 6 is an explanatory diagram showing the behavior of the printing paper associated with the operation of the paper ejection device following FIG. 5;

FIG. 7 is an explanatory diagram showing the behavior of the printing paper following the operation of the paper ejection device following FIG. 6;

FIG. 8 is an explanatory diagram showing the behavior of the printing paper accompanying the operation of the paper ejection device when the printing rate of the print image following the margin is relatively high.

FIG. 9 is an explanatory diagram showing the behavior of the printing paper following the operation of the paper ejection device following FIG. 8;

FIG. 10 is an explanatory diagram showing the behavior of the printing paper following the operation of the paper ejection device following FIG. 9;

FIG. 11 is an explanatory diagram showing the behavior of the printing paper following the operation of the paper ejection device following FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... plate cylinder, 2 ... stencil paper, 3a, 3b ... communication hole (exhaust side air flow path), 9 ... separation claw, 9a ... tip of separation claw, 11,
Reference numeral 12: pulley, 13: endless flat belt, 14: suction fan (air suction device), 14a: wind outlet (exhaust air passage), 15: fan housing (intake / exhaust air passage), 15a ...
Ventilation port (intake-side air flow path), 16: suction box (intake-side air flow path), 16a: suction hole (intake-side air flow path), 17: third air duct (exhaust-side air flow path), 17a: air outlet , 20... Second air duct (exhaust-side air flow path), 2
2a: drive shaft, 22b: driven shaft, 25: first air duct (exhaust-side air flow path), 30: printing paper, 50: discharge belt transport section, A: pressing contact section (predetermined pressing position).

Claims (2)

[Claims] An image corresponding to the stencil sheet is transferred to the printing sheet by rotating the stencil sheet around the outer peripheral surface and rotating the stencil sheet to press the printing sheet at a predetermined pressing position. In the paper discharge device of a stencil printing machine, the print paper on which an image has been transferred is peeled off from the plate cylinder that conveys the print paper downstream while passing through the predetermined pressing position, and is discharged through a predetermined paper discharge path. A discharge belt transport unit that is disposed in the predetermined discharge path, is driven at a speed higher than the peripheral speed of the plate cylinder, and has air permeability; and a rotation direction downstream of the plate cylinder from the predetermined pressing position. A separating claw that is disposed near the plate cylinder on the side thereof and that separates the printing paper from the plate cylinder by contacting the leading end of the printing paper that has passed the predetermined pressing position; and one unit that sucks air. An air suction device, and the air suction device The suction side air flow path that is arranged on the suction side of the air suction device and applies the suction effect of the air suction device to the paper discharge belt conveyance unit; An exhaust-side air passage through which air passes; and an exhaust passage provided in the exhaust-side air passage and located near the separation claw, between the plate cylinder and the printing paper having passed the predetermined pressing position. A paper discharge device for a stencil printing press, comprising: a blowout port for blowing air in a side air flow path. 2. The paper discharge device for a stencil printing machine according to claim 1, wherein the outlet is located near the downstream side in the rotation direction of the plate cylinder from the separation claw.