JP2007245510A - Printing plate discharging apparatus and stencil printing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new printing plate discharging apparatus capable of preventing a master released from a printing drum with any strength from winding itself around a pair of printing plate discharging rollers, and realizing preventing the master from winding itself around a pair of the printing plate discharging rollers by a simple and inexpensive constitution, and to provide a stencil printing apparatus having it. <P>SOLUTION: In a shape of an elastic blade 32a on a blade roller 32 of a pair of the printing plate discharging rollers 30, lengths of a plurality of the elastic blades 32a extending in the centrifugal direction from a roller stem part 32b are formed alternately in the circumferential direction of the blade roller 32, and equally formed in the axial line direction of the rotating shaft 38, namely, their tips are formed all together in the same rotating shaft line direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a stencil discharging apparatus for discharging a master, also called a used stencil sheet, wound around an outer peripheral surface of a printing drum, and a stencil printing apparatus having the same.

  Conventionally, a master that has been heated and perforated and engraved is wound around the outer peripheral surface of a rotatable plate cylinder, and ink is supplied by an ink supply means provided inside the plate cylinder. The printing paper (hereinafter referred to as “paper”) is continuously pressed against the pre-printed master on the plate cylinder by a pressing means such as to cause ink to ooze out from the plate cylinder opening part and the master punching part. A thermal digital stencil printing apparatus for performing printing is known.

The plate cylinder has a configuration in which a mesh screen made of a resin or metal mesh is wound around a porous support cylinder. Hereinafter, in this specification, the “plate cylinder” is expressed as “print drum” provided on the outer peripheral portion thereof, and the “plate cylinder” is sometimes simply referred to as “print drum”.
Master mixed Japanese paper fiber or synthetic fiber, or Japanese paper and synthetic fiber constituting a porous support (hereinafter simply referred to as “support”) into a thermoplastic resin film (hereinafter simply referred to as “film”). It has a laminate structure in which things are bonded together. The thickness of the film is generally about 1 to 2 μm. The master film surface is brought into contact with the heating element of the thermal head, the thermal head is operated in the main scanning direction, and the plate is heated and punched while moving the master in the sub scanning direction by a platen roller or the like as a conveying means. .
A used master used for printing is sandwiched between a pair of plate discharge rollers of a plate discharge device, peeled off from the outer peripheral surface of the plate cylinder, and accommodated in a plate discharge box.

  As a good example of a conventional plate discharging device, a blade roller is provided with a plurality of elastic blades extending radially in the centrifugal direction on the side of one roller of the plate discharging roller pair, and the elastic blade is elastically bent on the outer peripheral surface of the other roller. The master is peeled off by the elastic blades (hereinafter referred to as “peeled master”) while being brought into contact with deformation, and the one of the above is hit by striking the peeled master with a restoring repulsive force due to elastic deformation of the elastic blades. 2. Description of the Related Art There is known a plate discharging device that does not wind around the outer peripheral surface of a roller. The elastic blade is formed in a rectangular column or plate shape having a rectangular cross section, and one roller and the elastic blade come into contact with the peripheral surface of the other roller at a substantially equal width ratio. (For example, refer to Patent Document 1).

In addition, it is arranged in the vicinity of an openable / closable clamper (holding means) that clamps and holds the front end of the pre-printed master in conjunction with the opening / closing operation of the clamper, and is wound around the outer peripheral surface of the printing drum. A base paper locking device in a stencil printing machine having an elastic thin plate (kicking-out means) provided with a plurality of claw-like members for kicking out the tip of a used master in a substantially centrifugal direction of the printing drum along the axial direction of the printing drum Is already known (see, for example, Patent Document 2).
According to the technique described in Patent Document 2 (Japanese Patent Laid-Open No. 6-247031 (= Japanese Patent No. 2803654)), the clamper can be opened at a predetermined angle required for feeding and discharging, respectively, so that it is relatively simple. It is possible to use an automatic plate-feeding and automatic plate-removing device with a simple mechanism, and an elastic thin plate that swings in conjunction with the clamper is opened at a large angle necessary for plate removal at the plate-release position, and the printing drum Since the plate cylinder is swung in a direction that protrudes in the centrifugal direction, it is possible to reliably remove the used master (stencil paper) and to simplify the mechanism to reduce the size and weight of the device. Therefore, it is possible to provide a base paper locking device that can be achieved, is reliable, and can be produced at low cost.

  Further, according to the plate discharging device described in Patent Document 3 (Japanese Patent Application Laid-Open No. 2004-195873), the rotation of the plate discharging roller pair is started before the used leading end of the master is opened by the holding unit, and the above For example, a low-strength master having a relatively thin support is configured by holding the rotation operation of the pair of discharge rollers while the tip of the used master is held by the pair of discharge rollers for a predetermined time. Even so, the used master between the plate discharge roller pair (the nip portion) and the outer peripheral surface of the printing drum is securely extended before the plate discharge storing operation is performed. This ensures that the tip of the plate is clamped and prevents the plate from being stored in a slacked state with one side or local part of the used master not being pinched, and is almost constant over the entire width of the master. Feeding the amount of the master, for example, in a master storage portion, to stabilize the folding operation when the used master housing, is that prevents becomes plate discharge jam caught or broken in the middle.

By the way, in the stencil printing apparatus, the ink passes through the perforated part of the Japanese paper fiber and film, which is a porous support, and is transferred to the printing paper. However, if the support is thick, it enters the void of the support. When the amount of wasted waste ink that is discarded increases, or when the support fibers are intertwined in a complicated manner, or when thick fibers cross the perforated part, the passage of ink is obstructed. There has been a problem that a phenomenon called “fibrous eyes” in which a solid portion of an image is lost or a thin line or a character is cut or faint occurs.
Therefore, in recent years, attempts have been made to reduce image quality degradation due to the fiber mesh by reducing the thickness of the porous support itself or reducing the support fiber to reduce waste ink and the like.
As described above, when the support body that bears the strength of the master is thinned or the density is lowered, the strength (rigidity / rigidity) of the master itself is greatly lowered, and it becomes easier to bend than the conventional one. In addition, since the production of such a master is technically high level, the master itself is expensive.

JP 2000-43394 A JP-A-6-247031 JP 2004-195873 A

  Several measures have been taken to prevent the master from winding around the discharge roller. Examples of such measures include Patent Document 2 (Japanese Patent Laid-Open No. 6-247031 (= Patent No. 2803654)), Patent What was described in the literature 3 (Unexamined-Japanese-Patent No. 2004-195873) etc. is known.

In the technique described in Patent Document 2 (Japanese Patent Laid-Open No. 6-247031 (= Patent No. 2803654)), the elastic thin plate (kicking-out means) described above swings in conjunction with the clamper and is formed on the clamper base. Further, since it is swung in a direction in which the printing drum (plate cylinder) protrudes in the centrifugal direction from the U-shaped groove (concave portion), reliable removal of the used master (stencil paper) is provided.
However, it is very difficult to completely eliminate the wrapping of the used master around the discharge roller, and the leading end of the master released from the clamper bounces back to the discharge roller that starts to rotate rapidly, resulting in unstable behavior. There is a problem in that only one side or a local portion of the master is not sandwiched between the pair of discharge rollers, and the master is wound around the pair of discharge rollers. In particular, when a low-strength master having a relatively thin support is peeled and discharged from the outer peripheral surface of the printing drum, even if the elastic thin plate (kicking means) is used, the strength (strength of the master) ) Lowers, the behavior of the master tip when the tip of the used master is released from the clamper becomes unstable, and it becomes easy to corrugate and the entry into the plate removal device becomes unstable. There was a problem.

In the plate discharging apparatus described in Patent Document 3 (Japanese Patent Application Laid-Open No. 2004-195873), even a low-strength master having a relatively thin support as described above, The tip portion is securely clamped to prevent it from being broken or caught in the middle and becoming a discharged plate jam.
However, even in Patent Document 3, it is very difficult to completely eliminate the winding of the used master around the discharging roller, and the tip of the used master released from the clamper is rebounded by the rotating discharging roller. There is a problem that the behavior becomes unstable, and only one side of the master is not sandwiched between the plate discharge roller pair, and the master is wound around the plate discharge roller pair.

  In addition, since the production of a master that reduces the image quality deterioration due to the fiber eye by reducing the thickness of the porous support itself or by thinning the support fiber is technically high level, The master itself becomes expensive. Therefore, when high image quality is not required, a low-cost master, that is, a master with high strength is used. When such a high-strength master is discharged by the plate discharging apparatus described in Patent Document 3 (Japanese Patent Application Laid-Open No. 2004-195873), the leading end portion of the high-strength master jumps into the rotating plate discharging roller pair. Therefore, the leading end of the master is more rebounded than in the case of a low-strength master, which causes unstable behavior and may cause winding of the discharge roller pair. It was.

Accordingly, the present invention has been made in view of the above-described circumstances, and can prevent a master having any strength peeled from a printing drum from being wound around a pair of discharge rollers, and the master can be wound around a pair of discharge rollers. It is a first object of the present invention to provide a novel stencil printing apparatus and a stencil printing apparatus having the stencil printing apparatus that can realize prevention with a simple and inexpensive configuration.
Further, in addition to the first object or independently of the first object, the present invention can reliably control the tip of the used master at the nip portion of the discharging roller pair by appropriately controlling the rotational speed of the discharging roller pair. It is a second object of the present invention to provide a novel plate discharging apparatus that can be drawn into and held between the two and extending the master substantially uniformly and a stencil printing apparatus having the same.

In order to solve the above-described problems and achieve the above-described object, the invention according to each claim employs the following characteristic means / invention specific matters (hereinafter referred to as “configuration”).
The invention described in claim 1 has a pair of discharge rollers that pulls in while separating and peeling the used master wound around the outer peripheral surface of the printing drum provided with holding means for holding the leading end of the master that has been subjected to plate making. A blade member that rotates in synchronization with the one roller is provided on one roller side of the plate discharge roller pair, and the blade member includes a plurality of elastic blades extending in the centrifugal direction from the outer peripheral surface of the one roller. In the plate discharging apparatus, wherein the elastic blade is in contact with the outer peripheral surface of the other roller of the plate discharging roller pair while being elastically deformed, the plurality of elastic blades extending in the centrifugal direction from the rotating shaft of the blade member. The lengths are different in the circumferential direction of the roller, and are substantially equal in the rotational axis direction.

Here, “the lengths of the plurality of elastic blades are formed so as to be different in the circumferential direction of the roller” means that 1 in the circumferential direction of the roller as shown in the embodiments and modifications described later. In addition to the state in which the blades are alternately formed or the state in which a plurality of blades are alternately formed, the state in which a plurality of short elastic blade groups are formed between the long elastic blades, and the long elastic blades are rollers. This includes a state in which at least one short elastic blade is formed between a plurality of long elastic blade groups formed continuously in the circumferential direction.
In addition, “being formed approximately equally in the direction of the rotational axis” means that the length of the elastic blade is within the tolerance setting in addition to the length of the elastic blade being equal in the rotational axis direction of the blade member. means. In other words, it means that the tips of the elastic blades are on the same circumferential surface, that is, the tips of the elastic blades are aligned (the same applies hereinafter).

  According to a second aspect of the present invention, in the plate removing apparatus according to the first aspect, the shape including the thickness of the blades is different corresponding to the plurality of elastic blades having different lengths.

  According to a third aspect of the present invention, in the plate discharging apparatus according to the first or second aspect, after the holding means opens the tip of the used master, the plate discharging roller pair is started to rotate, and the printing drum is used. Regarding the rotational speed of the plate discharging roller pair when pulling out the used master while peeling, the used master is separated until the tip of the used master is clamped by the plate discharging roller pair. It is configured to rotate at a lower speed than the rotational speed of the pair of discharging rollers when the leading end is nipped and conveyed, and the rotational speed is gradually increased.

  According to a fourth aspect of the present invention, there is provided a pair of discharge rollers that pulls in while separating and peeling the used master wound around the outer peripheral surface of the printing drum provided with a holding means for holding the tip of the master that has been subjected to plate making. A blade member that rotates in synchronization with the one roller is provided on one roller side of the plate discharge roller pair, and the blade member includes a plurality of elastic blades extending in the centrifugal direction from the outer peripheral surface of the one roller. In the plate discharging apparatus in which the elastic blade is brought into contact with the outer peripheral surface of the other roller of the plate discharging roller pair while being elastically deformed, the holding means releases the tip of the used master, and then the plate discharging roller The rotational speed of the discharge roller pair when the pair is started to rotate and pulled out while peeling the used master from the printing drum is used by the discharge roller pair. Until the leading edge of the star is clamped, it is rotated at a lower speed than the rotational speed of the pair of discharge roller when the leading edge of the peeled used master is clamped and transported, and the rotational speed is gradually increased. It is characterized in that it is configured to be faster.

  The invention according to claim 5 is provided with a holding means for holding the leading end of the master that has been subjected to plate making, a printing drum that wraps the master that has been subjected to the plate making around the outer peripheral surface, and a swingable arrangement in the vicinity of the holding means, Kicking means comprising a plurality of claw-like portions for kicking out the tip of the used master wound around the outer peripheral surface of the printing drum in a substantially centrifugal direction of the printing drum, along the axial direction of the printing drum; 5. A stencil printing apparatus comprising a stencil printing apparatus for peeling and stenciling a used master on the outer peripheral surface of a printing drum, wherein the stencil printing apparatus is as defined in any one of claims 1 to 4. A stencil printing apparatus is characterized.

According to the present invention, the above-described problems can be solved and a new stencil printing apparatus and a stencil printing apparatus having the same can be provided. The main effects of the invention are as follows.
According to the first aspect of the present invention, the lengths of the plurality of elastic blades extending in the centrifugal direction from the rotating shaft of the blade member are formed to be different in the circumferential direction of the roller, and are substantially equal in the rotating shaft direction. Because of the formation, the used master of any strength can be securely held between the discharge roller pair at the time of discharging, so that the used master is rebounded and becomes unstable, It can be prevented from being wound around the pair of discharge rollers, and can be realized with a simple and inexpensive configuration.

  According to the second aspect of the invention, since the shapes including the thickness of the blades are made to correspond to the plurality of elastic blades having different lengths, the lengths of the elastic blades are staggered in the circumferential direction of the roller. However, it is possible to prevent the pair of discharge roller from vibrating during rotation and preventing the used master from waving and winding around the pair of discharge rollers when the tip of the used master is pulled in or during conveyance.

  According to the third aspect of the present invention, with the above-described configuration, the tip of the used master is reliably pulled into and pinched, for example, in the nip portion of the plate discharge roller pair, so that the gap between the outer peripheral surface of the printing drum and the plate discharge roller pair is The used master can be stretched almost uniformly, so that it is almost the same across the master width direction, unlike the case where the discharged master storage operation is performed in a state where one side of the used master or the local part is not pinched. A fixed amount of master over the entire surface can be fed into, for example, the master storage unit, so that the folding operation when storing the used master is stabilized, and it is possible to prevent the paper from being folded or caught in the middle as a result of jamming. In addition to the effects of the invention described in claim 1 or 2, it is possible to more reliably prevent the used master from being wound around the pair of discharge rollers, and to perform a good discharge operation. Obtain.

  According to the invention described in claim 4, with the above configuration, the tip of the used master is securely pulled into and pinched, for example, in the nip portion of the plate discharge roller pair, so that the gap between the outer peripheral surface of the printing drum and the plate discharge roller pair is The used master can be stretched almost uniformly, so that it is almost the same across the master width direction, unlike the case where the discharged master storage operation is performed in a state where one side of the used master or the local part is not pinched. A constant amount of master can be sent to the master storage unit, for example, so that the folding operation when storing the used master is stabilized, and it is possible to prevent the paper from being folded or caught in the middle as a result of jamming. become.

  According to the fifth aspect of the present invention, it is possible to provide a stencil printing apparatus having a plate discharging apparatus that exhibits the effects of the respective inventions.

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

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS.
First, based on FIG. 1, the outline | summary of a structure of the stencil printing apparatus 100 in this embodiment is demonstrated. The stencil printing apparatus 100 is inputted by an image reading device (scanner) 50 having a known configuration for reading an image of a document (not shown) and image information read by the image reading device 50 or an external connection device such as a personal computer (not shown). A plate making device 51 that makes the master 8 based on image information and feeds it, and a paper feeding device 52 that feeds printing paper P (hereinafter referred to as “paper P”) on a paper feed tray 58 as a paper feed tray. And a printing drum 1, a paper discharge conveying device 53 that sucks and conveys the printed paper P peeled from the printing drum 1, and a paper discharge in which the paper P conveyed by the paper discharge conveying device 53 is discharged and accommodated A sheet discharge tray 54 as a table, a plate discharging device 55 for peeling and storing the used master 8 from the outer peripheral surface of the printing drum 1 and the like are provided.

Hereinafter, the configuration around each of the devices and the printing drum 1 will be described in detail.
As shown in FIG. 1, the plate making apparatus 51 includes a holder member (not shown), a platen roller 10, a thermal head 11, a cutter 12, a reverse roller pair 13, and a guide plate 14.
The master 8 can be fed out from a master roll 8a wound around the core material 8b in a roll shape. The master roll 8a is rotatably supported by a holder member (not shown) via a core member 8b. The master 8 has a laminate structure in which, for example, a polyethylene terephthalate (PET) -based film is bonded to a support made of Japanese paper fiber or synthetic fiber, or a mixture of Japanese paper and synthetic fiber with an adhesive. Used.
If the master 8 is a conventional master, for example, the thickness of a film of polyethylene terephthalate (PET) or the like is about 1-2 μm, the thickness of the support is about 45-55 μm, and the total thickness is about 50-60 μm. Is used. On the other hand, the thickness of the porous support itself can be reduced or the support fiber can be made thin to reduce image quality deterioration due to the fiber mesh while also reducing the waste ink during the plate removal operation. In the case of the high-quality master 8, for example, the film configuration is the same as that of the conventional master, and the support has a thickness of about 25 to 30 μm and a total thickness of about 30 to 35 μm. As described above, the high-quality master 8 is relatively thin and low-strength as compared with the conventional master, so that the waist strength of the high-quality master 8 is that of the conventional master. Compared with it, it has fallen by about 30 to 50%.

A platen roller 10 rotatably supported by a plate making unit side plate (not shown) and a thermal head 11 having a large number of heating elements in the main scanning direction are provided downstream of the master 8 in the feeding direction X1. The master 8 is pressed against the platen roller 10 by a thermal head 11 biased by a biasing means such as a spring member (not shown). The thermal head 11 is relatively movable toward and away from the platen roller 8 via the master 8.
The platen roller 10 is rotationally driven in a clockwise direction by a stepping motor (not shown), whereby the master 8 is drawn out from the master roll 8a.
On the further downstream side of the platen roller 10, a guillotine type cutter 12 for cutting the master-made master 8 into a predetermined length is provided. The cutter 12 has an upper blade 12a as a movable blade and a lower blade 12b as a fixed blade. The cutter 12 is not limited to the above, and a rotary blade moving type may be adopted.

On the downstream side of the cutter 12, a pair of reversing rollers 13 rotatably disposed on the plate making unit side plate is disposed, and the pair of reversing rollers 13 are provided in pressure contact with each other. The reverse roller pair 13 is set to a speed slightly higher than the peripheral speed of the platen roller 10, and applies an appropriate tension to the master 8 while sliding between the master 8. On the downstream side of the pair of reversing rollers 13, a curved guide plate 14 is provided that guides the leading end of the master 8 that has been subjected to plate making to a clamper 7 that will be described later.
Although not shown, an automatic document feeder (ADF) that separates and conveys a document is provided above the image reading device 50. The image reading device 50 has a well-known configuration and function capable of reading a document conveyed by the ADF while automatically automatically conveying it, or reading a document placed on a contact glass surface (not shown) without using the ADF. Have.

As shown in FIGS. 1 and 2, the printing drum 1 has a cylindrical plate cylinder disposed on the outer periphery thereof. The plate cylinder is provided with a plurality of mesh screens (not shown) on the outer periphery of a supporting cylindrical body composed of a hole portion 1a formed by opening a large number of ink-permeable holes and a non-ink-permeable non-hole portion 1b. It has a layered configuration.
The support cylindrical body including the opening 1a and the non-opening 1b is formed of a thin metal plate such as stainless steel. The opening 1a is shown in a satin pattern in FIGS. 1 and 2, and is formed over a predetermined range on the circumference thereof excluding the periphery of the clamper 7 arrangement portion. The non-opening portion 1b is shown hatched in FIGS. 1 and 2, and is formed around the clamper 7 placement portion. The mesh screen is wound around a region substantially corresponding to the non-opening portion 1b of the support cylindrical body. For example, a resin or metal net-like ink-permeable region portion, and this ink-permeable region portion And a leather portion as an ink non-passing region.

  As shown in FIG. 2, both ends of the support cylindrical body are fixed to a pair of drum flanges 9 (showing the back side of the paper in FIG. 2) as end plates disposed on the front side and the back side of the paper. Has been. The printing drum 1 is rotatably supported around an ink pipe 5 that also serves as a support shaft 5 via a pair of drum flanges 9. The printing drum 1 is connected to a main motor 15 as a printing drum driving unit via a known driving transmission unit such as a gear or a belt, and the driving force from the main motor 15 is transmitted to the printing drum 1 in FIGS. It is rotationally driven in the middle arrow direction A (clockwise). The main motor 15 is composed of, for example, a DC motor, and is fixed to the stencil printing apparatus main body side.

The printing drum 1 can be stopped in the vicinity of the plate discharging position that also serves as the home position and the plate feeding position. Here, as shown in FIG. 2, the home position (printing position) refers to the rotational position of the printing drum 1 where the clamper 7 is positioned substantially on the left side of the printing drum 1 or diagonally upward to the left. It means a close position. The plate feeding position refers to the rotational position of the printing drum 1 where the clamper 7 is positioned substantially on the right side in FIG.
The configuration in which the printing drum 1 is positioned and stopped at the home position (discarding position) and the plate feeding position is the same as that shown in FIG. 1 of Japanese Patent Laid-Open No. 6-247031 proposed by the applicant of the present application, for example. is doing. That is, as disclosed in FIG. 1 of the above-mentioned publication, a evacuation plate positioning pin for defining a home position (a evacuation position) implanted in the drum flange 9 of the printing drum 1 (the plate cylinder 5 in the above publication). (22), a plate-feeding positioning pin (21) for defining a plate-feeding position, and a stencil printing main body side (side plate 23 shown in FIG. A plate-shaped wide opening for use in plate removal and plate feeding that engages the plate-positioning positioning pin (22) or the plate feeding positioning pin (21) fixed on the back side of the bent portion (32a) on the other end side. It is mainly comprised from the positioning guide (39) in which the positioning groove | channel (38) connected to this opening part (37) and this opening part (37) was formed.

The stencil printing apparatus 100 includes angle detection means (rotation position detection means) that detects the rotation angle of the printing drum 1, that is, the rotation position of the printing drum 1. As shown in FIG. 2, the angle detection means includes an encoder plate 16, an encoder sensor 17, a drum sensor filler 18, and a drum home position sensor 19.
An encoder plate 16 having a large number of slits is attached to the output shaft of the main motor 15. On the stencil printing machine main body side in the vicinity of the encoder plate 16, an encoder sensor 17 comprising a photo interrupter (transmission type optical sensor) that holds the encoder plate 16 at a predetermined interval is disposed. By detecting the number of pulses generated in cooperation with the rotation operation of the encoder plate 16 by the rotation drive of the main motor 15 by the encoder sensor 17, the rotation angle and the rotation speed of the printing drum 1 are detected. Yes. The encoder plate 16 and the encoder sensor 17 are photo-rotary encoders and constitute an incremental type pulse encoder.

The drum flange 9 on the back side shown in FIG. 2 of the printing drum 1 has a substantially “<” shape in a front view protruding further from the drum flange 9 for detecting and indexing the rotational position of the printing drum 1. A drum sensor filler 18 is fixed.
On the other hand, a predetermined position on the stencil printing apparatus main body side facing the drum flange 9 on the back side of the printing drum 1 shown in FIG. 2 engages with the drum sensor filler 18 when the home position, which is also the discharging position, is occupied. Accordingly, a drum home position sensor 19 is disposed as a drum home position detecting means for detecting the home position. The drum home position sensor 19 is a transmissive optical sensor.

The rotation position of the printing drum 1 shown in FIG. 2 represents a state where the printing drum 1 occupies the home position and is stopped. At this time, the drum home position sensor 19 is in a state in which its optical path is blocked by the drum sensor filler 18 on the printing drum 1 side and the home position of the printing drum 1 is detected to be on. This home position is a reference for detecting the rotation angle (rotation position) of the printing drum 1.
Instead of the pulse encoder disposed on the main motor 15 side, it may be disposed on the printing drum 1 side. If the same thing as the above-mentioned pulse encoder is arranged on the printing drum 1 side, the backlash of the gear, belt or the like (rotational driving force transmission means) connecting the main motor 15 and the printing drum 1 or the belt The rotation angle of the printing drum 1 can be directly and accurately detected by eliminating variations and fluctuations in the rotation angle of the printing drum 1 due to elongation.

Inside the printing drum 1, side plates (not shown) are fixed to the ink pipe 5 at intervals in the axial direction. Between these side plates, an ink roller 2 is rotatably provided with its shaft portion supported. The ink roller 2 is rotationally driven in the same direction in synchronism with the printing drum 1 by drive transmission means such as a gear or a belt (not shown).
A doctor roller 3 is provided with a slight gap from the outer peripheral surface of the ink roller 2, and the doctor roller 3 is an ink reservoir 4 having a substantially wedge-shaped cross section formed between the ink roller 2 and the doctor roller 3. A thin film is supplied to the outer peripheral surface of the ink roller 2 while measuring the ink. The ink in the ink reservoir 4 is sucked from an ink pack or the like provided outside the printing drum 1 by an ink supply device (not shown), supplied dropwise from the supply hole 5a of the ink pipe 5, and the ink roller 2 and the doctor roller 3 It is kneaded by rotation. The printing drum 1 constitutes a drum unit integrated with the ink supply device and the ink pack in the axial direction with respect to the stencil printing apparatus main body, and is detachable from the stencil printing apparatus main body. .

  As shown in FIGS. 1 to 3, a stage 6 having a flat surface and a clamper base 48 as a master clamping member are provided on the surface of the non-opening portion 1 b of the printing drum 1 along one bus line of the printing drum 1. Is provided. The clamper base 48 is made of, for example, a ferromagnetic material. As shown in detail in FIGS. 3 to 7, the clamper base 48 has a substantially U-shaped groove portion 48a for loosely fitting a plurality of claw-like portions 36a, 36b formed integrally with a kick-out member 36 described later. A plurality of 48b are formed in the direction of the clamper shaft 25.

In parallel with the stage 6 and the clamper base 48, the clamper 7 as a holding means for clamping and holding the tip of the master 8 that has been made is rotatable by a predetermined angle via the clamper shaft 25, that is, the free end of the clamper 7 is It is supported so that it can swing. As shown in FIG. 3, the clamper 7 and the clamper base 48 are provided to extend in the axial direction of the printing drum 1 at least longer than the dimension in the master width direction Y of the master 8 indicated by the two-dot chain line of the maximum size used. ing.
As shown in detail in FIGS. 3 to 7, the clamper 7 is mainly composed of a magnet plate 7 a made of an elastic permanent magnet (for example, a rubber magnet) and a clamp plate 7 b. Opposed to the fixed clamper base 48, it can be opened and closed. On the clamp plate 7b, lift claws 7c bent in a crank shape and hanging pieces 7d are integrally formed at both ends in the direction of the clamper shaft 25. The clamp plate 7b is integrally formed of a metal such as stainless steel. The magnet plate 7a is adhered and fixed to the clamp plate 7b with an appropriate double-sided tape or the like.
FIG. 1 and FIG. 3 show a state in which the leading end of the master 8 that has been subjected to the plate making supplied from the plate making device 51 is sandwiched and clamped with the clamper base 48 by the closing operation of the clamper 7.

At one end of the clamper shaft 25, a clamper drive lever 26 similar to the clamper drive lever (20) shown in FIGS. 8 and 9 of the above-mentioned JP-A-6-247031 is attached substantially integrally. The clamper driving lever 26 is provided with the plate feeding operating arm (25) or the plate discharging operating arm (32) shown in FIGS. 1, 2, 6, and 7 of the above-mentioned JP-A-6-247031. An engagement surface 26a is formed that engages with the engagement portions (26, 35) of the plate feeding operation arm (25) or the plate removal operation arm (32) when the first or third position is occupied. .
On the other hand, on the stencil printing machine main body side, a printing drum 1 similar to the base paper locking device (60) shown in FIGS. 1, 2, 6 and 7 of the above-mentioned JP-A-6-247031 is provided. The rack shown in FIG. 2 is the same as the plate feeding operating arm (25), the plate discharging operating arm (32), and the rack driving motor (45) that opens and closes the clamper 7 when the home position (plate discharging position) and the plate feeding position are occupied. An opening / closing device (not shown) having a drive motor 45 and the like is disposed.

In the vicinity of the clamper 7, a kick-out member 36 is slidably disposed. The kick-out member 36 has claw-like portions 36 a and 36 b that kick out the tip of the used master 8 wound around the outer peripheral surface of the printing drum 1 in the substantially centrifugal direction of the printing drum 1 along the axial direction of the printing drum 1. And a plurality of kicking-out means provided. The kick-out member 36 is made of an elastic thin plate such as stainless steel, for example, and has a symmetrical shape on both the left and right sides with respect to the center of the printing drum 1 in the axial direction. In addition to the plurality of claw-like portions 36a, 36b formed on the free end side of the kick-out member 36 in the form of comb teeth, an engagement claw 36c that can contact the lift claw 7c of the clamp plate 7b is provided. It is integrally formed at both ends.
In the vicinity of the engaging claw 36c in the drum flange 9 at both ends of the printing drum 1, escape recesses 9a are formed to avoid interference with the engaging claw 36c when the clamper 7 is opened and closed. 4 to 7, the shape of the drum flange 9 and the thickness of the kick-out member 36 and the clamper base 48 are exaggerated and enlarged.

In Japanese Patent Application Laid-Open No. 2004-195873 (Patent Document 3), the length in the direction along the outer peripheral surface of the printing drum 1 among the plurality of claw-like portions 36 a and 36 b corresponds to the both side edges of the used master 8. The claw-shaped portion 36a disposed in this manner is formed to be longer than the claw-shaped portion 36b disposed corresponding to the inside of the used master 8, but in this embodiment, The lengths of the claw-like portions 36a and 36b may be the same.
As shown in FIGS. 1 and 3, when the clamper 7 is closed, the claw-like portions 36 a and 36 b of the kick-out member 36 are fitted and housed in the grooves 48 a and 48 b of the clamper base 48. ing. As will be described later, the claw-like portions 36a and 36b of the kick-out member 36 protrude from the clamper base 48 in the substantially centrifugal direction of the printing drum 1 only in the plate discharging process in which the clamper 7 is expanded more than a predetermined angle θ2. As a result, the tip of the used master 8 is kicked out in the same direction.

The base end portion of the kick-out member 36 is fixed to a rotary shaft 37 that is rotatably supported by a predetermined angle on the stage 6 closer to the rear side in the arrow direction A in FIG. 2 of the printing drum 1 than the arrangement portion of the clamper shaft 25. ing. The rotation shaft 37 is provided in parallel with the clamper shaft 25 along the axial direction of the printing drum 1. The free end portion of the kick-out member 36 is rotated and oscillated counterclockwise around the rotation shaft 37 in FIG. 2 in conjunction with the opening / closing operation of the clamper 7.
As shown in FIGS. 5 and 7, the kick-out member 36 is configured so that the plater operating arm (32) (not shown) swings to the third position and engages with the clamper driving lever 26. When the opening is greater than the angle θ2, the rocker 7 swings in conjunction with the opening operation of the clamper 7.

  Although the explanation is mixed, when clamping the master 8 that has been pre-made or the master 8 that has not been pre-made, the plurality of grooves 48a and 48b of the clamper base 48 are arranged so as to be inside the tip of the master 8. The tip of the master 8 is clamped and clamped between the clamper base 48 and the clamper 7.

In FIG. 1 and FIG. 2, the plate discharging device 55 arranged on the left side of the printing drum 1 has a plate discharging roller pair 30 that holds the used master 8 wound around the outer peripheral surface of the printing drum 1 and pulls it while peeling. is doing. The discharge roller pair 30 has an upper discharge roller 31 and a lower discharge roller 33 that are in pressure contact with each other. The rotation shafts 38 and 39 that form the shafts of these rollers are rotatably supported by a discharge unit side plate (not shown). ing. A drive gear (not shown) is fixed to the lower plate roller 33, and the lower roller 33 is connected to, for example, a stepping motor 75 as a drive unit via drive transmission means such as a gear train (not shown) that meshes with the lower drive roller. Yes.
The stepping motor 75 has a function as a driving unit that rotationally drives the discharge roller pair 30. As a result, the upper plate roller 31 and the lower plate roller 33 are opposed to each other by a stepping motor 75 as shown in FIG. 2, and in FIG. 2, the upper plate roller 31 is clockwise and the lower roller 33 is counterclockwise. It is driven to rotate around. As the driving means, a DC motor or the like may be used, but a relatively inexpensive stepping motor 75 that can be easily changed and rotated is used.
As shown in FIG. 9, a plurality of plate discharge roller pairs 30 are provided at intervals in the axial direction of the printing drum 1, and on each side of the plate discharge roller top 31 in each plate discharge roller pair 30, An impeller 32 (hereinafter referred to as “blade roller 32”) is provided as a blade member that rotates synchronously.

  As shown in FIGS. 2, 8 and 9, the blade roller 32 (blade roller 32) includes a roller-shaped roller base portion 32b fixed to a rotary shaft 38 on the plate discharge roller 31, and a discharge roller from the roller base portion 32b. It has a plurality of elastic blades 32a extending radially in the centrifugal direction (radial direction) of the upper 31 and having tips (free ends) protruding outward from the outer peripheral surface / outer diameter of the upper plate roller 31. ing. The upper plate roller 31 and the blade roller 32 are made of an elastic material such as nitrile rubber or silicon rubber having oil resistance and ink resistance. If the upper plate roller 31 and the blade roller 32 are integrally formed of the same material, manufacture and assembly are facilitated.

The elastic blade 32 a contacts the tip of the used master 8 to draw the used master 8 into the nip portion between the upper plate discharging roller 31 and the lower plate discharging roller 33, and by hitting the used master 8. It has a function of preventing the peeled master 8 from sticking to the peripheral surface of the upper plate roller 31.
As shown in detail in FIG. 8, the shape of the elastic blade 32 a is such that the lengths of the plurality of elastic blades 32 a extending in the centrifugal direction from the roller base portion 32 b including the rotation shaft 38 are different in the circumferential direction of the blade roller 32. They are formed alternately and are equally formed in the axial direction of the rotation shaft 38 (hereinafter referred to as “rotation axis direction”), that is, their tips are formed in the same rotation axis direction. This unique shape of the elastic blade 32a makes it easy to hook the tip of the used master 8.

  Here, the length of the short blades 32a (hereinafter simply referred to as “short blades”) in the elastic blades 32a is 0.5 to 0.00 when the long blade 32a (hereinafter simply referred to as “long blades”) is 1. It is set and formed at a rate of about 7. The thickness of the blade is about 0.5 to 2 mm. For example, when the long blade is about 1.5 to 2 mm, the short blade is set and formed to about 0.5 to 1.5 mm. This is to prevent a difference in conveying force between the long and short blades when the used master 8 peeled from the lower plate roller 33 is conveyed. FIG. 9 is a cross-sectional view of the short blade portion of the elastic blade 32a in the blade roller 32. The length of the short blade of the elastic blade 32a is equal in the rotation axis direction and the tips are aligned. Represents.

As shown in FIGS. 8A and 8B, the elastic blade 32a is in a state immediately before the state shown in FIG. 2, that is, as described in detail later, the tip of the used master 8 is a kicking member. By being kicked up by 36, at the time of plate removal coming into contact with the opened end of the used master 8, the tip of the elastic blade 32a is deformed so as to bend against the outer peripheral surface of the plate lowering roller 33. At this time, if the length of the elastic blade 32a is short, the elastic force becomes strong, and a force F1 for pushing down the lower discharge roller 33 as shown by the thick arrow in FIG. 8B acts. Therefore, as shown in FIG. 8C, when the long and short blades have the same thickness t and are formed of the same material, the force F2 (> F1) acts, and the plate discharge roller pair 30 vibrates during rotation in the direction of the arrow in the drawing, and the leading edge of the master 8 and the conveyance may become unstable. It is desirable to provide a difference in t. When vibration is generated, the master 8 undulates when the leading end of the master 8 is pulled or during conveyance, and the wrapping around the discharge roller pair 30 is likely to occur. Here, “winding around the plate discharge roller pair 30” means that the tip of the used master 8 is wound around at least one member of the upper plate roller 31, the blade roller 32, and the lower plate roller 33. Yes.
Note that the blade width of the elastic blade 32a (the depth direction in FIG. 8 and the horizontal dimension in FIG. 9) is set to 3 to 5 mm for both long and short blades.

  That is, if the length of all the elastic blades 32a is formed long and the tips thereof are aligned, the tip of the used master 8 is rebounded, but in the circumferential direction of the blade roller 32 as in this embodiment. Since the short blades are provided alternately, a space 40 is formed in the portion of the short blades sandwiched between the long blades, and the leading end portion of the master 8 enters the space 40 and is not rebounded, so that the nip portion of the discharge roller pair 30 Can be reliably pulled into. Although it is possible to make the tip of the master 8 easily enter by widening the pitch at which the elastic blades 32a are provided, the conveyance force at the nip portion of the plate discharge roller pair 30 is weakened. There are limitations. As an example of an appropriate range of this pitch, the angle formed by the adjacent elastic blades 32a around the rotation center of the rotation shaft 38 of the blade roller 32 is about 45 ° to 72 °.

  A plate discharging apparatus 55 of this embodiment having a plate discharging roller pair 30 provided with blade rollers 32 in which the long and short blades of the elastic blade 32a are formed in a specific shape and length as described above, and Japanese Patent Application Laid-Open No. 2004-195873. As in (Patent Document 3), the waist strength of the master 8 with the plate discharging device (55) having the plate discharging roller pair (30) provided with the impeller (32) formed on the long blade (elastic blade 32a). As a result of carrying out a comparative test by changing the number of types to several types, the one shown in FIG. 8A and FIG. 8B of the first embodiment of the present invention does not wrap around the plate discharge roller pair 30, and the plate discharge There was no significant jam, and there was a clear significant difference in the effect.

The lower discharge roller 33 is made of resin (for example, ABS resin or polyacetal resin), and the outer peripheral surface thereof is used to reduce sticking of the used master 8 containing ink, that is, the used master. Tooth contact processing and knurling processing are performed so that the contact area with 8 can be reduced.
Since the elastic blade 32a has a columnar shape with less contact with the used master 8, it is used more than the conventional elastic blade (13) shown in FIG. 3 of Japanese Patent Laid-Open No. 2000-43394. The sticking of the already master 8 can be reduced.

On the left side of the plate discharge roller pair 30, a compression plate 34 is provided as a compression member that is rotatably supported at one end between the plate discharge unit side plates and swings about the shaft portion in the arrow direction (vertical direction). . The free end side of the compression plate 34 passes through a position close to the plate discharge roller pair 30 and presses against the peeled master 8 discharged by the plate discharge roller pair 30, that is, the waste master 8d, on the wall surface of the plate discharge box 35. And the waste master 8d is compressed and stored while moving to the back of the discharge box 35.
The compression plate 34 is driven at a predetermined timing by a motor or the like (not shown). The plate removal box 35 is detachably attached to a plate removal apparatus main body (not shown) so that the full disposal master 8d can be disposed of appropriately.

Next, with reference to FIG. 2, the opening / closing control configuration and the plate ejection control configuration of the clamper 7 of the stencil printing apparatus 100 will be described.
In FIG. 2, the control means 77 is for mainly controlling the opening / closing of the clamper 7 and the drive control of the discharge roller pair 30 in the discharge control of the stencil printing apparatus 100 according to the present embodiment. In order to simplify the explanation below, there is a main control means (not shown) for controlling the overall operation of the stencil printing apparatus 100 other than the above control. The main control means and the control means 77 are mutually connected with a command signal and ON / OFF. The description will be made assuming that an off signal or a data signal is transmitted / received.

The control means 77 includes a CPU (central processing unit), an I / O (input / output) port, a RAM (read / write storage device), a ROM (read only storage device), a timer (not shown), etc., not shown. A microcomputer having a configuration in which they are connected by a signal bus is provided.
The CPU of the control means 77 is electrically connected to the encoder sensor 17 and the drum home position sensor 19 via the input port and each sensor input circuit, and relates to the rotation angle of the printing drum 1 from the encoder sensor 17. An output signal (data signal: pulse signal) and an output signal (on / off signal) for detecting the home position of the printing drum 1 are received from the drum home position sensor 19. As a result, the control unit 77 outputs a signal related to the home position that serves as a reference for the rotation angle of the printing drum 1 from the drum home position sensor 19 and the number of pulses from the encoder sensor 17 related to the rotation amount (rotation speed) of the main motor 15. Based on the above, the rotational position of the printing drum 1 is calculated, and the timing (starting of rotation driving) of the plate discharge roller pair 30 described later is determined.

  The CPU of the control means 77 is electrically connected to the stepping motor 75 via the motor drive circuit 76 including the output port and a control circuit (not shown), and sends a command signal for controlling the stepping motor 75 to the motor drive circuit. 76. The control means 77 is electrically connected to the rack drive motor 45 of the opening / closing device for opening / closing the clamper 7 via the motor drive circuit including the output port and a control circuit (not shown). Is transmitted to the motor drive circuit.

The RAM of the control means 77 temporarily stores the calculation result of the CPU, the output signal related to the rotation angle of the printing drum 1 from the encoder sensor 17, and the home position of the printing drum 1 from the drum home position sensor 19. The output signals for detection are stored at any time, and these signals are input / output.
In the ROM of the control means 77, the used master 8 relating to the start timing (rotation drive start timing) and the rotation drive end timing of the discharge roller pair 30 is expanded for the CPU to perform a control function described later. Time required for the relationship, the relation data of the number of pulses supplied to the stepping motor 75 for rotationally driving the plate discharging roller pair 30 ”,“ supplying to the stepping motor 75 for changing the peripheral speed (rotational speed) of the plate discharging roller pair 30 ” “Relation data between pulse frequency and number of pulses output from encoder sensor 17 relating to rotation angle of printing drum 1”, “program for changing frequency of pulse supplied to stepping motor 75”, and “opening / closing operation of clamper 7” And a program relating to the plate removal operation, etc. "are stored in advance.

The CPU of the control means 77 refers to an output signal (pulse number signal) relating to the rotation angle of the printing drum 1 from the encoder sensor 17 and an output signal for detecting the home position of the printing drum 1 from the drum home position sensor 19. However, by starting the rack drive motor 45, the stepper motor 75 is moved via the motor drive circuit 76 so that the plate discharge roller pair 30 starts to rotate after the clamper 7 releases the tip of the used master 8. Regarding the rotational speed (circumferential speed) of the plate discharge roller pair 30 when controlling and pulling out the used master 8 from the printing drum 1, the tip of the used master 8 is pinched by the plate discharge roller pair 30. In the meantime, the pair of discharge rollers 30 is used when the tip of the used master 8 that has been peeled is sandwiched and peeled and conveyed. There is a control function for controlling the stepping motor 75 via the motor drive circuit 76 so that the discharge roller pair 30 rotates at a lower speed than the rotation speed (circumferential speed) and the rotation speed (circumferential speed) gradually increases. .
Here, the control operation for gradually increasing the rotational speed (circumferential speed) of the plate discharge roller pair 30 is continued for a predetermined time, so that the used between the printing drum 1 and the nip portion of the plate discharge roller pair 30 is used as described later. The time required for the master 8 to extend is, for example, the size and shape of the component parts constituting the plate discharge roller pair 30, the peripheral speed when driven, and the strength of the master (the waist It goes without saying that it varies depending on the strength of the

  The rotation speed (circumferential speed) of the pair of discharge rollers 30 is changed by changing the frequency (pps: pulse per second) of the pulses supplied to the stepping motor 75 by the control means 77, that is, changing the pulse interval (narrowing the pulse interval). It can be done easily by acceleration, constant speed at regular intervals, and deceleration by widening the pulse interval). For example, the control unit 77 can be easily configured using a commercially available microcomputer.

As shown in FIG. 1 and the like, on the lower side of the printing drum 1, a pressing unit 21 that presses the paper P against the master 8 on the printing drum 1 that has been made is provided. The pressing means 21 includes an arm shaft 22a rotatably supported on a side plate of a stencil printing apparatus main body (not shown), a press roller arm pair 22 having one end fixed to the arm shaft 22a, and the press roller arm pair 22 The other end side has a press roller 23 that is rotatably supported with a shaft portion supported.
A cam follower (not shown) is provided on one end side of the arm shaft 22a, and the press roller 23 is connected to the printing drum by a biasing means such as a tension spring (not shown) along a cam (not shown) that rotates in synchronization with the printing drum 1. It comes in contact with and away from 1. The press roller 23 is held at a position indicated by a solid line separated from the printing drum 1 by a locking means (not shown) except during printing. As the pressing means, an impression cylinder having a diameter substantially the same as the outer diameter of the printing drum 1 may be used.

The paper feeding device 52 is a paper feeding tray 58 as a vertically movable paper feeding table on which the paper P is stacked, and paper feeding as separation paper feeding means for separating and feeding the paper P one by one from the top. The rollers 59 and 60 and the separation roller 61, and the registration roller pair 20 that conveys the separated and fed paper P to a printing pressure portion between the printing drum 1 and the press roller 23 at a predetermined timing.
On the lower left side of the printing drum 1, a peeling claw 62 that is swingable around a shaft portion that peels the paper P from the surface of the printing drum 1 in the vicinity of the printing drum 1 is provided. The paper P peeled off by the peeling claw 62 is transported while being attracted by the suction force of the fan 64 by the transport roller 63 of the paper discharge transport device 53, and is discharged to a paper discharge tray 54 as a paper discharge tray.

Next, the operation of the stencil printing apparatus 100 will be described. As an initial state of the stencil printing apparatus 100, the used master 8 used in the previous printing remains attached to the outer peripheral surface of the printing drum 1, and the clamper 7 of the printing drum 1 is substantially left in FIG. The rotation position of the printing drum 1 located sideways or diagonally upward to the left, that is, the rotation angle of the printing drum 1 occupies 0 ° (home position: plate removal position) and is stopped.
In this initial state, a document is set on an ADF (not shown), and the number of prints is input and set using a numeric keypad on an operation panel (not shown). Next, when a start button or the like provided on the operation panel is pressed, a start signal is output, and this is used as a trigger to first execute a plate discharging process.

The start signal triggers the rack drive motor 45 of an opening / closing device (not shown) that opens and closes the clamper 7. When the rack drive motor 45 of the opening / closing device is driven, the clamper 7 is opened as shown in FIG. 2, and in conjunction with this, the kicking member 36 kicks up the tip of the used master 8. Is called.
That is, as shown in FIG. 5 and FIG. 7, the plate discharge operation arm (32) (not shown) is swung to the third position, and the plate discharge angle is larger than the predetermined angle θ1 required for the clamper 7 to supply the plate. By being in a state of being opened at θ2, the engaging claw 36c is lifted in conjunction with the lift of the lift claw 7c, whereby the claw-like portions 36a, 36b of the kick-out member 36 are removed from the grooves 48a, 48b of the printing drum 1. By swinging in a direction protruding substantially in the centrifugal direction, the tip of the used master 8 is reliably kicked up and released over the entire width in the master width direction Y including its both side edges. In this state, the used tip end portion of the master 8 is reliably transferred to the discharge roller pair 30. As a result, it is possible to more reliably prevent the occurrence of a plate jam.

  Next, in response to a command from the control means 77, the stepping motor 75 is started to rotate (starts up), so that the discharge roller pair 30 starts to rotate at a low speed. Then, the rotational speed (circumferential speed) of the plate discharge roller pair 30 is gradually increased, and this is continued for a predetermined time and then stopped. By performing such an operation, the upper end portion of the used master 8 that has been released is brought into contact with the elastic blade 32a of the blade roller 32 to the plate roller pair 30 rotating at a low speed. And the lower part of the discharge roller 33 are surely drawn into and pinched. Then, the stepping motor 75 is controlled so as to achieve a rotational speed necessary to extend the used master 8 between the plate discharge roller pair 30 and the outer peripheral surface of the printing drum 1 substantially uniformly.

  Note that the time from when the rack drive motor 45 is started (after the clamper 7 is released and the tip of the used master 8 becomes open / free) until the stepping motor 75 is started is used. Although it depends on the strength of the master's waist, it is known from the experimental results that a time of about 0.1 to 0.5 seconds is desirable. If it is less than 0.1 seconds, the tip of the used master 8 released by the elastic blade 32a of the blade roller 32 may be rebounded as in the prior art (see, for example, Patent Document 3). If it exceeds 5 seconds, it is not preferable from the point that FPT (first print time) until the first printed matter including plate printing is obtained becomes long.

Details of the rotational speed control of the plate discharge roller pair 30 will be described with reference to FIGS. 10 and 11.
10 and 11, the first circumferential speed is the circumferential speed of the pair of discharge rollers 30 when the tip including the tip of the used master 8 is sandwiched and gripped (the speed of the outer peripheral surface of the upper 31 of the discharge rollers). It is set to 0.1 to 0.5 times the third peripheral speed described later.
The second peripheral speed means the peripheral speed of the pair of discharge rollers 30 when the master 8 is clamped and gripped and then the master 8 is stretched substantially uniformly with the printing drum 1. It is set to 0.5 to 1.0 times the third circumferential speed described later.
The third peripheral speed is the peripheral speed of the pair of discharge rollers 30 when the master 8 is stretched substantially uniformly at the second peripheral speed and then the master is peeled and conveyed from the printing drum 1, in other words, used. It means the peripheral speed of the plate discharge roller pair 30 at the time of pull-in when the master 8 is sandwiched and pulled and conveyed, and is set to 1.0 to 1.4 times the peripheral speed of the printing drum 1.

When the opened end of the used master 8 is reliably pulled into the nip portion between the upper plate discharge roller 31 and the lower plate discharge roller 33, the rotational speed (circumferential speed) of the plate discharge roller pair 30 may be lower. Desirably, the discharge roller pair 30 is rotated simultaneously with the rotation of the printing drum 1 to hold the used master 8 and pull and convey it by peeling. That is, it is relatively 10% to half of the third circumferential speed. It is set to a slow first peripheral speed (specifically, 0.1 to 0.5 times the third peripheral speed).
Further, when the tip of the used master 8 is drawn into the nip portion of the plate discharge roller pair 30, the used master 8 between the plate discharge roller pair 30 and the outer peripheral surface of the printing drum 1 is stretched substantially uniformly. It is desirable that the speed be relatively higher than the first peripheral speed, and a relatively slow second peripheral speed that is half or equivalent to the third peripheral speed (specifically, 0.5-3 of the third peripheral speed). 1.0 times).

That is, in response to a command from the control means 77, for example, data related to a pulse with a pulse frequency that starts rotating at 0.2 times the third circumferential speed, accelerates to a circumferential speed of 1.0 times in 2 seconds, and then stops. Then, the control is performed by calling from the ROM and supplying the predetermined pulse to the stepping motor 75. In this way, the acceleration time (required time for the rotation operation) of the peripheral speed (first peripheral speed to second peripheral speed) of the plate discharge roller pair 30 until the leading end portion of the master 8 is drawn and extended is 0.5-2. Seconds.
Here, when the peripheral speed of the plate discharge roller pair 30 is a constant speed and is less than 0.5 times the peripheral speed at the time of pulling in, the FPT becomes too long, and also the tip of the used master 8 From the point that the used master 8 between the plate discharge roller pair 30 and the outer peripheral surface of the printing drum 1 is extended substantially uniformly after the plate is drawn into the nip portion of the plate discharge roller pair 30. Is also not preferable.

  Further, if the peripheral speed when the leading end of the used master 8 that has been released is reliably pulled into the nip portion between the upper plate roller 31 and the lower plate roller 33 exceeds 0.5 times, it is not preferable from the following points. . That is, the peripheral speed of the pair of discharge rollers 30 is rotated at a high speed with respect to the used master 8 to be sandwiched and gripped, so that the corner of the tip of the master 8 is bounced back and bent. It was wound up in a state or torn. If the master 8 with the broken ear or the master 8 with its torn part is removed and stored in the release box 35, it is no longer folded into a beautiful bellows shape, and the amount of stored plate is reduced. Since the master piece and the master that is bounced become unstable and wraps around the plate discharge roller pair 30 and interferes with the next plate discharge, the peripheral speed at the time of pulling is 0.1 to 0. If the peripheral speed is set to 5 times, these problems can be solved, and the tip of the used master 8 can be prevented from breaking or tearing at the corner of the tip of the used master 8. This is because it is possible to pinch and pinch.

  In the above-described rotation speed control, the control means 77 “to gradually increase the rotation speed” means that the master 8 is printed from the time when the tip of the used master 8 is pinched / clamped by the pair of discharge rollers 30. The rotational speed (circumferential speed) of the plate discharge roller pair 30 is gradually increased until it extends substantially uniformly with the drum 1 (after the rotation of the plate discharge roller pair 30 is started, the first circumferential speed to the second circumferential speed). Change to speed). In FIG. 10, the slopes until the first peripheral speed and the third peripheral speed are reached indicate a slow-up curve necessary for starting the rotational driving of the stepping motor 75.

As shown in FIGS. 11 (a) to 11 (d), several variations are conceivable for changing the rotational speed (circumferential speed) of the pair of discharge rollers 30 from the first peripheral speed to the second peripheral speed. (T ″ = 0.5 to 2.0 seconds (s)).
First, as shown in FIG. 11 (a), there is a case where a linear change is made from the first peripheral speed to the second peripheral speed.
Second, as shown in FIG. 11 (b), after maintaining the first circumferential speed for a certain time t ′ (= t ″ / 3 to t ″ / 2), linearly to the second circumferential speed. The case where it changes is mentioned.
Third, as shown in FIG. 11 (c), after maintaining the first circumferential speed for a certain time t ′ (= t ″ / 3 to t ″ / 2), it rapidly changes to the second circumferential speed. In the case of maintaining up to t ″.
Fourthly, as shown in FIG. 11D, there is a case where the curve is changed so as to draw a curve R (for example, a Sin curve).

After the tip of the used master 8 is caught in the plate discharge roller pair 30 and the rotation operation of the plate discharge roller pair 30 elapses for a predetermined time, the tip of the master 8 which has been peeled off by a detection means (not shown) is removed. When it is detected that the sheet is drawn into the nip portion, the rotation of the plate discharge roller pair 30 is temporarily stopped. After that, when the clamper 7 is closed by the operation of the opening / closing device, the main motor 15 starts to rotate (starts) immediately, so that the printing drum 1 moves around the support shaft 5 at two points in FIG. By starting to rotate in the direction of arrow A (clockwise direction) indicated by a chain line, and simultaneously with this, the plate discharge roller pair 30 is driven to rotate again. While being sandwiched between the lower plate discharge roller 33 and being prevented from sticking to the upper plate discharge roller 31 by the blade roller 32, it is peeled sequentially from the surface of the printing drum 1, and the bellows is formed in the space between the compression plate 34 and the discharge plate box 35. It is stored while being folded.
As an example of the detection means, a reflection type optical device disposed near the nip portion of the plate discharge roller pair 30 in FIG. 2 (near the upper left of the plate discharge path formed through the nip portion in FIG. 2). The master detection sensor which consists of sensors is mentioned.

At the time of this plate discharging operation, a third rotation in which the peripheral speed at the time of pulling in of the pair of discharging rollers 30 is equal to or faster than the peripheral speed (drum peripheral speed) of the printing drum 1 at the time of discharging according to a command from the control means 77. Data relating to a pulse having a predetermined pulse frequency such that the speed (specifically, 1.0 to 1.4 times the drum peripheral speed) is called from the ROM, and the predetermined pulse is supplied to the stepping motor 75. To do. The switching timing of the rotation speed of the plate discharge roller pair 30 is performed simultaneously with the rotation of the printing drum 1.
Here, if the peripheral speed of the discharge roller (pulling speed at the time of drawing) is less than 1.0 times the peripheral speed of the drum, the used master 8 on the printing drum 1 that is nipped and transported by the pair of discharge rollers 30 bumps. From the viewpoint of causing a plate jam, or the ink adhering to the used master 8 comes into contact with the components or members in the stencil printing apparatus 100 and stains the inside of the printing apparatus. If it exceeds 4.times., The used master 8 on the printing drum 1 is forcibly pulled, so that the master 8 being nipped and conveyed may be torn, and it is not possible to be folded into a beautiful bellows. It is not preferable because it disappears.

  When peeling of the used master 8 from the surface of the printing drum 1 is completed, the printing drum 1 rotates and stops until the clamper 7 reaches a plate feeding position located substantially on the right side in FIG. As shown in FIGS. 4 and 6, when the printing drum 1 is stopped at the plate feeding position, the opening / closing device operates to swing the plate feeding operating arm (25) (not shown) to the first position. In addition, the clamper 7 is open within a predetermined angle θ1 required for plate feeding. At this time, the lift claw 7c and the engaging claw 36c are in contact with each other and are located above the escape recess 9a, and the claw-like portions 36a and 36b of the kick-out member 36 are inserted into the grooves 48a and 48b of the clamper base 48. Therefore, the plate-feeding (plate-making) of the master 8 at the plate-making master 8 by the clamper 7 and the clamper base 48 at the time of plate-feeding is reliably performed without interfering with the claw-like portions 36a and 36b.

  In the plate feeding standby state, the document is conveyed to the image reading device 50, and the heating element of the thermal head 11 is energized in a pulsed manner according to image information via a CCD, an A / D converter, a plate making control device, and the like. The Then, the thermal head 11 is operated in the main scanning direction, and a film portion of the master 8 is heated while the stepping motor (not shown) rotates and the master 8 is conveyed in the sub scanning direction by the platen roller 10 and the reverse roller pair 13. Plate making to be perforated is performed.

  The guide plate 14 guides the leading end of the master 8 that has been subjected to plate making between the clamper base 48 and the clamper 7 in the stage 6, and the leading end of the master 8 that has been pre-made based on information such as the number of steps of a stepping motor (not shown). When the clamper 7 is determined to have reached the clamping area of the clamper 7, the clamper 7 is closed by the opening and closing device, so that the leading end of the master 8 that has been made is sucked and clamped. A master winding operation for revolving the printing drum 1 at a speed substantially the same as the conveying speed of the master 8 and winding the master-made master 8 around the outer peripheral surface of the printing drum 1 while sandwiching the leading end of the mastering master 8. Is done.

  When it is determined from the number of steps of a stepping motor (not shown) that the plate making has been completed, the cutter 12 is actuated to cut the master 8 and the platen roller 10 and the reverse roller pair 13 are stopped. When the rear end of the master 8 is completely pulled out of the plate making apparatus 51 by the rotation of the printing drum 1, the master winding operation around the printing drum 1 is completed.

  In parallel with this plate feeding / winding operation, the compression plate 34 in the plate discharging device 55 rotates in the clockwise direction, and the waste master 8d stored in a bellows shape is moved along the wall surface of the plate discharging box 35 to the back. The waste master 8d is compressed and stopped at a predetermined position while being pressed. After a predetermined time, the compression plate 34 rotates counterclockwise and returns to the initial position.

When the winding of the master 8 having been subjected to the plate making onto the printing drum 1 is completed, the sheet feeding rollers 59 and 60 are operated, and the sheet P is removed from the sheet feeding tray 58 by the separation action of the sheet feeding roller 60 and the separation roller 61. Only one sheet is separated, fed in the sheet conveyance direction X, and conveyed between the printing drum 1 and the press roller 23 by a registration roller pair 20 that rotates at a predetermined timing. When the paper sensor (not shown) detects the entry of the paper P, the locking means (not shown) of the pressing means 21 is released so that the press roller 23 rotates the cam (not shown) and the biasing means (not shown) such as a tension spring. Is applied by pressing the paper P against the master 8 on the printing drum 1 and the master 8 is filled with ink.
The paper P is peeled off from the surface of the printing drum 1 by the peeling claw 62 approaching and separating from the printing drum 1, transported by the paper discharge transport device 53, and discharged and stacked on the paper discharge tray 54. Thereafter, the set number of prints is performed in the same operation.

Since the stencil printing apparatus 100 of the first embodiment is based on the stencil printing apparatus described in Patent Document 1 (Japanese Patent Laid-Open No. 2000-43394), this is improved so as to achieve the above-described effects. Needless to say, the basic effects described in paragraphs “0038” and “0041” of Japanese Patent Application Laid-Open No. 2000-43394 can be obtained (the same applies to the following modifications).
Similarly, the stencil printing apparatus 100 according to the first embodiment is based on the base paper locking device described in Patent Document 2 (Japanese Patent Laid-Open No. 6-247031) and has been improved so as to exhibit the effects described later. Therefore, it goes without saying that the basic effects described in the above-mentioned conventional technology and Japanese Patent Application Laid-Open No. 6-247031 can be obtained (the same applies to the following modifications).

FIG. 12 shows a first modification of the first embodiment.
This modified example 1 is different from the first embodiment shown in FIGS. 8 and 9 only in that a blade roller 32A instead of the blade roller 32 is used as compared with the blade roller 32 of the plate discharge roller pair 30 in the first embodiment. Compared with the blade roller 32, the blade roller 32A has a width b in the rotation axis direction of the short blade as compared with that of the long blade as shown in FIG. 12B, not the short blade thickness t of the plurality of elastic blades 32a. The only difference is that it is narrower.
For example, the width b of the long blade is 3 to 5 mm, whereas the width b of the short blade is set to about 1.5 to 2 mm. The thickness t of the elastic blade 32a is set and formed at about 1.5 to 2 mm for both the long and short blades. Also in this modified example, the length of the long and short blades in the elastic blade 32a in the centrifugal direction is set and formed in a specific shape as in the first embodiment. a), the same as that shown in FIG.

FIG. 13 shows a second modification of the first embodiment.
This modification 2 is different from the blade roller 32 of the plate discharge roller pair 30 in the first embodiment shown in FIGS. 8 and 9 only in that a blade roller 32B instead of the blade roller 32 is used. Compared with the blade roller 32, the blade roller 32 </ b> B has a thickness t of the long and short blades of the plurality of elastic blades 32 a equal to about 0.5 to 1.5 mm, and 10 at the root of the long blade. The only difference is that the elasticity of the long blades is increased by adding a taper of about 10 degrees. Note that the widths in the depth direction of the drawing in the drawing of the long and short blades of the plurality of elastic blades 32a are both set and formed to be the same. Also in this modification, the operation and advantage are the same as those shown in FIGS. 8A and 8B.
Needless to say, in the first and second modifications, the above-described effects can be obtained by applying a control operation including the rotational speed control operation of the plate discharge roller pair 30 in the first embodiment.

  As described above, the present invention has been described with respect to specific embodiments including examples. However, the configuration of the present invention is not limited to the above-described embodiments, and may be configured by appropriately combining them. It will be apparent to those skilled in the art that various embodiments and examples can be made within the scope of the present invention according to the necessity and application thereof.

1 is a partial cross-sectional front view of a stencil printing apparatus showing a first embodiment of the present invention. FIG. 2 is a partial cross-sectional enlarged front view showing main control structures and operations around a clamper and a plate discharging apparatus in the stencil printing apparatus of FIG. 1. FIG. 2 is a plan view around a clamper, a clamper base, and a kick-out member in the stencil printing apparatus of FIG. 1. FIG. 2 is a perspective view showing an operation at a plate feeding position around a clamper and a kick-out member in the stencil printing apparatus of FIG. 1. FIG. 2 is a perspective view showing an operation at a plate discharging position around a clamper and a kick-out member in the stencil printing apparatus of FIG. 1. It is a partial cross section front view which shows the operation | movement of FIG. It is a partial cross section front view which shows the operation | movement of FIG. (A), (b), (c) is a front view of the plate discharge roller pair of the plate discharge device in the stencil printing apparatus of FIG. FIG. 2 is a front view of a plate discharge roller pair of a plate discharge device in the stencil printing apparatus of FIG. 1. It is a speed diagram showing a specific example of the rotational speed (circumferential speed) control of the plate discharge roller pair. (A), (b), (c), (d) are speed lines showing various modes for changing from the first circumferential speed to the second circumferential speed in the rotational speed (circumferential speed) control of the pair of discharge rollers. FIG. (A) is a front view of the blade roller of the plate discharging apparatus in Modification 1, and (b) is a side view of the blade roller. FIG. 10 is a front view of a blade roller of a plate discharging device in Modification 2.

Explanation of symbols

1 Printing drum 7 Clamper 8 holding means Master (stencil paper)
25 Clamper shaft 26 Clamper drive lever 30 Plate discharge roller pair 31 Upper plate discharge rollers 32, 32A, 32B as one roller Blade blades (impellers) as blade members
32a Elastic blade 33 Lower plate discharge roller as the other roller 34 Compression plate 35 as compression member Discharge box 36 Kick-out members 36a and 36b as kick-out means 37 Claw-shaped portion 37 Rotating shaft 38 Rotating shaft 38 Rotating shaft 45 Rack Drive motor 48 Clamper base 48a, 48b Groove 55 Discharge device 75 Stepping motor 77 Control means 100 Stencil printing device t Elastic blade thickness b Elastic blade width Y Master width direction

Claims (5)

A plate discharging roller pair that holds the used master wound around the outer peripheral surface of the printing drum having a holding means for holding the front end of the plate-making master, and pulls it while peeling, and one of the plate discharging roller pairs A blade member that rotates in synchronization with the one roller is provided on the roller side, and the blade member includes a plurality of elastic blades extending in the centrifugal direction from the outer peripheral surface of the one roller, and the elastic blade is elastically deformed. While in the plate discharging device that is in contact with the outer peripheral surface of the other roller of the plate discharging roller pair,
The lengths of the plurality of elastic blades extending in the centrifugal direction from the rotation shaft of the blade member are formed so as to be different in the circumferential direction of the roller, and are formed substantially equal in the rotation axis direction. A plate removal device characterized by The plate discharging apparatus according to claim 1,
The plate discharging apparatus, wherein the shape including the thickness of the blades is different corresponding to the plurality of elastic blades having different lengths. In the plate discharging apparatus according to claim 1 or 2,
After the holding means releases the tip of the used master, the discharging roller pair starts to rotate, and the rotation speed of the discharging roller pair when pulling out the used master from the printing drum is peeled off. In contrast, until the tip of the used master is clamped by the pair of discharging rollers, the rotational speed of the pair of discharging rollers when the tip of the used master that has been peeled is held while being peeled is conveyed. A plate discharging apparatus characterized by being configured to rotate at a low speed and gradually increase its rotational speed. A plate discharging roller pair that holds the used master wound around the outer peripheral surface of the printing drum having a holding means for holding the front end of the plate-making master, and pulls it while peeling, and one of the plate discharging roller pairs A blade member that rotates in synchronization with the one roller is provided on the roller side, and the blade member includes a plurality of elastic blades extending in the centrifugal direction from the outer peripheral surface of the one roller, and the elastic blade is elastically deformed. While in the plate discharging device that is in contact with the outer peripheral surface of the other roller of the plate discharging roller pair,
After the holding means releases the tip of the used master, the discharging roller pair starts to rotate, and the rotation speed of the discharging roller pair when pulling out the used master from the printing drum is peeled off. In contrast, until the tip of the used master is clamped by the pair of discharging rollers, the rotational speed of the pair of discharging rollers when the tip of the used master that has been peeled is held while being peeled is conveyed. A plate discharging apparatus characterized by being configured to rotate at a low speed and gradually increase its rotational speed. A printing drum provided with holding means for holding the front end of the master that has been subjected to plate-making, and a printing drum for winding the master-made master around the outer peripheral surface; Kicking means provided with a plurality of claw-like portions for kicking out the used tip end of the used master in the substantially centrifugal direction of the printing drum along the axial direction of the printing drum, and use on the outer peripheral surface of the printing drum In a stencil printing apparatus comprising a plate discharging device for peeling and discharging a used master,
The stencil printing apparatus according to any one of claims 1 to 4, wherein the stencil printing apparatus is the stencil printing apparatus.

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