JP2009203072A - Sheet feeder and printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air feeder, and a printing device comprising that, capable of using an air suction drive source of a DC fan in a case with a small suction belt pitch, and a small drive (follower) roller diameter so as to achieve reduction of occupied space and compactness of the device, and to achieve reduction of occupied space and compactness of the device in the height direction especially when applied to stencil printing device. <P>SOLUTION: In the sheet feeder, a suction drive source chamber 17 is connected to a suction relay tube 13, and an air suction port 15a1 of a multiblade fan 15a on the upstream is connected to the suction drive source chamber 17. A fan connection duct 45 is connected to an air delivery port 15a2 of the multiblade fan 15a, and the fan connection duct 45 is connected to the air suction port 15b1 of the multiblade fan 15b on the downstream. Two multiblade fans 15a and 15b are thus serially connected to each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sheet feeding apparatus and a printing apparatus, and more specifically, separates sheets from a stacked sheet bundle by discharging air, and feeds the separated uppermost sheet while sucking air. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air suction type sheet feeding device for feeding and a printing apparatus having the same.

  As is well known, there are a friction type and an air type sheet feeding device (sheet feeding device) that takes out and feeds sheets one by one from the stacked sheet bundle (see FIG. 10 for the friction type). The air-type paper feeding device separates sheets from a sheet bundle by discharging air, and feeds the separated uppermost sheet while sucking air (for example, Patent Document 1). reference).

6 and 7 show an example of a conventional air-type paper feeding device 500 (hereinafter also referred to as “air paper feeding device 500”). The principle of the air feeding device 500 is roughly performed by the following processes (1) to (3).
(1) By blowing air a to the front end surface and side end surface of the sheet bundle 2, air enters between the sheets, and the sheets S of the sheet bundle 2 are separated and separated one by one as shown in FIG.
(2) By sucking only one uppermost sheet S1 of the separated sheets S1 and S, the sheet S1 is attached to and held on the suction belt 11.
(3) As the suction belt 11 rotates and travels, one sheet S1 is fed and conveyed.

  The operation of components (components) that function in the step (1) of blowing air a to the front end surface and side end surfaces of the sheet bundle 2 is as follows. As shown in FIG. 6, from the front of the sheet bundle 2, a flow of air a is created by a front air discharge fan 23 composed of a DC fan as a front air discharge drive source, and this air a passes through the front discharge chamber 20 and is discharged from the front. It exits from the outlet 21 and blows onto the front end surface (front end surface) of the sheet bundle 2.

Further, as shown in FIGS. 6 and 7, air a is also generated from a pair of left and right side air discharge fans 41, 41 composed of a DC fan as a side air discharge drive source, similarly from both left and right end surfaces of the sheet bundle 2. A flow is created, and this air a goes out through the side discharge chamber 42 and blows to each side end face of the sheet bundle 2. When each of the air is blown onto the front end surface and both end surfaces of the sheet bundle 2, the upper portion of the sheet bundle 2 is separated and separated one by one as shown in FIG.
Here, the side air discharge fans 41 and 41 and the side discharge chamber 42 constitute a side discharge unit 40. The front discharge unit and the side discharge unit 40 including the front discharge chamber 20 and the front air discharge fan 23 blow the air S onto the leading end surface and both end surfaces of the sheet bundle 2 stacked on the sheet feeding tray 3. Air separation means for separating the sheets one by one is configured.

The paper feed tray 3 is configured to be movable up and down by an elevating mechanism having an elevating motor as driving means (not shown). Above the sheet feed tray 3, the separated uppermost sheet S <b> 1 comes into contact with the rear end of the uppermost sheet S of the sheet bundle 2 stacked on the sheet feed tray 3. An upper limit detection sensor for occupying a paper feed position where suction feeding is possible (not shown, for example, a transmission type photo sensor is turned on by a filler provided on a roller-shaped member and a bracket that rotatably supports the member. / Off configuration) is provided. Based on a signal from the upper limit detection sensor (not shown), a control means (not shown) controls the lifting motor (not shown) so that the paper feed tray 3 maintains an appropriate height corresponding to the stack height of the sheet bundle 2. It has become.
In the paper width direction Y orthogonal to the paper transport direction X in the paper feed tray 3, a pair of side fences (not shown) for positioning and aligning both end faces of the paper bundle 2 are provided so as to be movable in the paper width direction Y. Each side fence is formed with an opening for allowing side air to pass therethrough.

Components (components) that function in the step (2) of sucking only one separated uppermost sheet S1 and the step (3) of conveying one sheet S1 by rotating and running the suction belt 11 are: The suction belt 11, the drive roller 14 a, the driven roller 14 b, the suction chamber 12, the suction relay pipe (duct) 13, the air suction drive fan 15, the suction drive source chamber 17, and the suction belt drive motor 47.
Above the uppermost sheet S1 in the sheet bundle 2, there is a suction belt 11 consisting of an endless belt stretched between a driving roller 14a and a driven roller 14b. The suction belt 11 has a number of holes 11a for air suction. Is formed. In FIG. 7, for the sake of simplification of illustration, the hole 11 a is illustrated as being formed in a specific range of the suction belt 11 between the driving roller 14 a and the driven roller 14 b. However, the holes 11a are formed at equal pitches on the lower side of the suction belt 11 and the upper sides of the rollers 14a and 14b over the entire sheet conveying direction (sheet feeding direction) X and the sheet width direction Y of the suction belt 11. Needless to say, this is the same (the same applies to FIGS. 2 and 12 described later).
On the left and right outer sides of the sheet feeding tray 3 on which the sheet bundle 2 is stacked, a sheet feeding unit 500A described later (almost all components that function in the above steps (1) to (3) including the sheet feeding tray 3). A pair of unit side plates (not shown) constituting the configuration) is disposed, and the driving roller 14a and the driven roller 14b can rotate in the arrow direction (clockwise direction) in FIG. 6 on the pair of unit side plates. It is pivotally supported. In an air sheet feeder that does not constitute a sheet feeding unit, the driving roller 14a and the driven roller 14b are arranged in a direction indicated by an arrow (clockwise direction) in FIG. 6 on a pair of side plates (not shown) fixed to the apparatus body. It is pivotally supported.
One end of the shaft of the drive roller 14a is connected to an output shaft 47a of a suction belt drive motor 47 as a belt drive means fixed to the one unit side plate side via a coupling 14c. The suction belt drive motor 47 is composed of, for example, a stepping motor that is easy and accurate in controlling the conveyance distance by variable speed control and rotation.

Between the driving roller 14a and the driven roller 14b, and surrounded by the upper and lower suction belts 11, a suction chamber 12 for sucking air a is provided. It has been. A suction relay pipe 13 is connected to and connected to one side of the suction chamber 12.
A drive source for sucking air is an air suction drive fan 15 as an air suction drive source, and a suction drive source chamber 17 is connected to and connected to the air suction drive fan 15. Therefore, the suction chamber 12 and the air suction drive fan 15 are connected and connected via the suction relay pipe (duct) 13 and the suction drive source chamber 17.
The suction belt 11, the drive roller 14 a, the driven roller 14 b, the suction chamber 12, the suction relay pipe 13, the air suction drive fan 15, the suction drive source chamber 17, and the suction belt drive motor 47 constitute the suction unit 10. .
In the suction unit 10 described above, the suction belt 11, the suction chamber 12, the suction relay pipe 13, the air suction drive fan 15, and the suction drive source chamber 17 constitute air suction means.
In the suction unit 10, the suction belt 11, the drive roller 14a, the driven roller 14b, and the suction belt drive motor 47 constitute sheet feeding means for feeding the paper S sucked and held by the air suction means. is doing.

The operations in the above steps (2) and (3) are as follows. That is, by driving the air suction drive fan 15, when the air a is sucked by the suction chamber 12 through the suction drive source chamber 17 and the suction relay pipe 13, the inside of the suction chamber 12 becomes negative pressure, Since the air a is sucked from the hole 11a of the suction belt 11 in the range facing the surface of the opening 12a of the suction chamber 12, the uppermost sheet S1 separated into one sheet in the step (1) is applied to the suction belt 11. Sticked and held by suction.
When the sheet S1 adheres to the suction belt 11, the suction belt drive motor 47 is driven to rotate the drive roller 14a in the direction of the arrow in FIG. The sheet S1 is conveyed to a pair of upper and lower registration rollers 113a and 113b disposed on the downstream side of the “paper feeding direction X”). After transporting the sheet S1 to the registration roller pair 113a, 113b, the suction belt drive motor 47 is stopped to stop the travel of the suction belt 11, and the suction operation is waited for a predetermined time. The remaining sheet S1 is conveyed by rotation of the registration roller pair 113a and 113b. When the rear end of the sheet S1 comes in the vicinity of the front plate 4 that abuts the front end surface of the sheet bundle 2, the sheet S separated into the next sheet by the same operation as described above adheres to the suction belt 11. . The air feeding system feeds paper by repeating these processes and operations.

  6A and 7B, reference numeral 500A denotes a paper feed unit that is integrally configured except for the pair of registration rollers 113a and 113b among the components constituting the air paper feeder 500. The paper feed unit 500A is configured to be detachable from, for example, an apparatus main body 50 of a stencil printing apparatus shown in FIG. 10 to be described later via attachment / detachment means including fastening means such as screws (not shown).

The suction force of the air is sucked from the total area (hereinafter referred to as “suction belt hole area”) of the holes 11a of the suction belt 11 located in the range facing the surface of the opening 12a of the suction chamber 12 and these holes 11a. It depends on the speed of the air. In order to increase the suction force of air, it is generally preferable that the suction belt hole area is large and the air speed is high. This is because the air suction force is increased and the function of sucking and holding the paper S is improved. The air suction force referred to here means the volume and air volume of air per unit time.
In order to increase the speed of the air sucked from the holes 11a of the suction belt 11, the suction relay pipe 13 having a cross-sectional area larger than the area of the total holes 11a of the suction belt 11 is preferable.
The conventional suction relay pipe 13 is
(A) As shown in FIGS. 6 and 7, suction was performed at one place from the side of the suction belt 11.
(B) As shown in FIG. 8, the suction is performed from the upper direction, which is the sheet suction direction.

By the way, in order to separate the sheets S of the sheet bundle 2 one by one in the sheet separating step (1), air a (hereinafter also referred to as “side air a”) to the left and right end faces of the sheet bundle 2. The spraying power of is important.
The blowing force F of the side air a is determined by the following expression of the blowing area (cross-sectional area) Ac and the air velocity (wind velocity) V. However, in the following equation, Q is the flow rate of the side air a, and ρ is the density of the side air a. That is, F = Q × V × ρ = Ac × V × V × ρ (∴Q = Ac × V).

JP 2007-31070 A

  However, with regard to the air suction force, in the method (a) of suctioning from one side from the side of the suction belt 11, the size and cross-sectional area of the suction relay pipe 13 are between the pitches of the suction belt 11, that is, the rollers 14a and 14b. It is determined by the distance between them (see FIG. 6). That is, the size and cross-sectional area of the suction relay pipe 13 are shorter than the distance between the suction belt pitches and smaller than the diameter of the drive (driven) roller 14a (14b) from the relationship shown in FIG.

Until now, because there was no space restriction, the suction belt hole area was smaller than the suction relay pipe (duct) cross-sectional area. However, if the space must be reduced, that is, the suction belt pitch is short, or the drive (driven) Although the diameter of the roller must be reduced, this also reduces the cross-sectional area of the suction relay pipe 13. That is, the suction belt hole area> the suction relay pipe (duct) cross-sectional area, and the suction force is reduced.
Assuming that there is a space limitation, assuming that an air feeding device is provided in a stencil printing device, especially in a printing device, a plate making unit is arranged in the height direction of the device body as shown in FIG. In the case of 100 or a different layout configuration, there is less space because the plate removing unit 70 is arranged. Therefore, a sheet feeding unit (sheet feeding device) arranged below the plate making unit 100 or the plate discharging unit 70. ) There is a strong demand for space saving and downsizing in the height direction Z of 110.

If the suction force is increased due to the relationship of the suction belt hole area> the suction relay pipe (duct) cross-sectional area, the air pressure passing through the suction relay pipe 13 is increased by increasing the static pressure of the air suction drive fan 15. It corresponded.
However, when the static pressure of the air suction drive fan 15 is increased, there is a limit in a DC (direct current) fan motor (hereinafter referred to as “DC fan”), and an AC (alternating current) motor used in a vacuum cleaner or the like. A large blower to drive was used. In this case, it is inevitable to secure a space in the height direction Z by a large blower itself, increase the size of the device, and increase the cost.

  On the other hand, FIG. 8 shows an example in which the above (b) relating to the air suction force is sucked from above, which is the sheet suction direction. In this method, the suction belt hole area is equal to the suction area, but between the upper suction belt 11 and the suction drive source chamber 17A, in particular, between the upper suction belt 11 near the drive roller 14a and the suction drive source chamber 17A. When the gap 19 is generated, air leaks, so that stable suction conveyance cannot be performed, and space saving and size reduction in the height direction Z cannot be achieved. In FIG. 8, a suction force acts between the suction chamber 12A and the upper and lower suction belts 11 and between the suction drive source chamber 17A and the suction belt 11 in the vicinity of the driven roller 14b, and tends to adhere. Therefore, it is a level that can be ignored as compared with the gap 19 of the part.

Next, problems related to the side air blowing force will be described. In order to reliably separate the sheets one by one with the side air, that is, to blow up the sheets, it is better that the speed of the side air is more reliably separated and the force applied per unit area is stronger.
For example, the side air of slow and weak force is used on both sides of paper, especially thick paper or coated paper (referred to as coated paper or art paper, hereinafter `` coated paper '') under high-temperature and high-humidity feeding conditions. Even if sprayed over the entire end face, the adhesion between the coated papers is high and cannot be separated. Even if the spray area is small, the faster the wind speed (side air speed), the more reliably the sheets can be separated one by one. This is because the configuration of the air feeding device 500 shown in FIGS. 6 and 7 separates coated paper under high-temperature and high-humidity feeding conditions using the side air speed and spray area as parameters. This was confirmed by an experiment. Therefore, I want to make the wind speed as fast as possible. The wind speed is proportional to the static pressure of the air drive source. The higher the static pressure, the faster the wind speed.

  Accordingly, the present invention has been made in view of the above-described problems and circumstances, and in a printing apparatus including an air feeding type sheet feeding apparatus and a stencil printing apparatus having the same, space saving and miniaturization of the apparatus are achieved. In order to save space and reduce the size of the device in the height direction, especially when applied to a stencil printing device, the distance between the suction belt pitches is reduced, or the diameter of the drive (driven) roller is reduced. Even in such a case, the first object is to be able to cope with the use of an inexpensive DC fan air suction drive source.

  In addition to the first object or independent of the first object, the present invention increases the static pressure as much as possible by using an inexpensive DC fan side air drive source (air blowing drive source). Therefore, a sheet feeding device that can increase the speed of the side air (wind velocity) and can reliably separate even cardboard or coated paper (coated paper, etc.) one by one, and a stencil printing apparatus having the same. A second object is to realize and provide a printing apparatus including 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 and configuration.
According to the first aspect of the present invention, there is provided an air suction means having an air suction drive source for sucking the separated uppermost sheet after separating the sheets one by one from the stacked sheet bundle, and the air suction means In the sheet feeding apparatus having a sheet feeding unit that feeds the sheet held by suction, the air suction drive source includes an air suction port for sucking air and an air discharge port for discharging air. It is composed of a plurality of sirocco fans, and the air suction port of the downstream sirocco fan adjacent to the upstream sirocco fan is connected to and connected to the air discharge port of the upstream sirocco fan. It is characterized by.

  According to a second aspect of the present invention, in the sheet feeding device according to the first aspect, the sirocco fans have the same static pressure specifications.

  According to a third aspect of the present invention, in the sheet feeding apparatus according to the first or second aspect, each of the sirocco fans comprises a DC fan that can change a static pressure and an air volume by changing a rotation speed. It is characterized by that.

  According to a fourth aspect of the present invention, in the sheet feeding apparatus according to any one of the first to third aspects, the air separation is performed such that the sheets are separated one by one by blowing air to both side end surfaces of the stacked sheet bundle. The air separating means includes a side air discharge port that blows air to each side end surface of the sheet bundle, and an air blowing drive source that is in communication with and connected to the side air discharge port. The blowing drive source is composed of a plurality of air blowing drive source sirocco fans having an air blowing drive source air suction port for sucking air and an air blowing drive source air discharge port for discharging air. The air blowing drive source air discharge port of the air blowing drive source sirocco fan has the downstream side air blowing drive source sirocco fan adjacent to the upstream air blowing drive source sirocco fan. Characterized by being arranged to communicatively connect the A spray drive source for air suction port.

  According to a fifth aspect of the present invention, in the sheet feeding apparatus according to the fourth aspect, the sirocco fan for each air blowing drive source has the same static pressure specification.

  According to a sixth aspect of the present invention, in the sheet feeding device according to the fourth or fifth aspect, the sirocco fan for each of the air blowing drive sources can change the static pressure and the air volume by changing the rotation speed. It is characterized by comprising a certain DC fan.

  According to a seventh aspect of the present invention, there is provided a printing apparatus for feeding a sheet to form a printed image on the sheet, the sheet feeding apparatus according to any one of the first to sixth aspects, and the sheet feeding apparatus. And a print image forming means for forming a print image on the sheet fed by the above.

  The invention according to claim 8 is a printing apparatus for feeding a sheet to form a printed image on the sheet, and printing on the sheet feeding apparatus according to claim 3 and the sheet fed by the sheet feeding apparatus. Print image forming means for forming an image, sheet type recognition means for recognizing the sheet type, and control means for controlling each sirocco fan according to the sheet type recognized by the sheet type recognition means It is characterized by that.

  The invention according to claim 9 is a printing apparatus for feeding a sheet to form a printed image on the sheet, and printing on the sheet feeding apparatus according to claim 3 and the sheet fed by the sheet feeding apparatus. Print image forming means for forming an image, sheet type recognition means for recognizing the sheet type, temperature detection means for detecting the temperature of the printing apparatus, the sheet type recognized by the sheet type recognition means and the temperature Control means for controlling each sirocco fan in accordance with the temperature of the printing apparatus detected by the detection means.

  According to a tenth aspect of the present invention, there is provided a printing apparatus for feeding a sheet to form a printed image on the sheet, and printing on the sheet feeding apparatus according to the sixth aspect and a sheet fed by the sheet feeding apparatus. A print image forming unit for forming an image, a sheet type recognizing unit for recognizing the type of the sheet, and the sirocco fan for each of the air blowing drive sources is controlled in accordance with the sheet type recognized by the sheet type recognizing unit. And a control means.

  The invention described in claim 11 is a printing apparatus for feeding a sheet to form a printed image on the sheet, and printing on the sheet feeding apparatus according to claim 6 and the sheet fed by the sheet feeding apparatus. Print image forming means for forming an image, sheet type recognition means for recognizing the sheet type, temperature detection means for detecting the temperature of the printing apparatus, the sheet type recognized by the sheet type recognition means and the temperature And control means for controlling the air blowing drive source sirocco fans according to the temperature of the printing apparatus detected by the detection means.

  According to a twelfth aspect of the present invention, there is provided a printing apparatus for feeding a sheet to form a print image on the sheet, and printing on the sheet feeding apparatus according to the sixth aspect and the sheet fed by the sheet feeding apparatus. The air blowing drive source sirocco fan is controlled by a print image forming means for forming an image, a double feed recognition means for recognizing the double feed of the sheet, and a double feed of the sheet recognized by the double feed recognition means. And a control means.

According to the present invention, it is possible to provide a novel sheet feeding apparatus and a printing apparatus having the same by solving the above problems. The main effects of the invention are as follows.
According to the present invention, in a printing apparatus including an air feeding type sheet feeding apparatus and a stencil printing apparatus having the same, in order to save space and reduce the size of the apparatus, particularly when applied to a stencil printing apparatus. In order to save space and reduce the size of the device in the height direction, for example, even when the distance between the suction belt pitches constituting the air suction means and the sheet feeding means is reduced or the diameter of the drive (driven) roller is reduced. With the above configuration, that is, a plurality of sirocco fans connected and connected in series as an air suction drive source composed of an inexpensive DC fan, the static pressure is increased and the sheet is sufficiently sucked and held to be fed. (Claims 1 to 3 and 7 to 9).

  Further, according to the present invention, a plurality of air blowing drive source sirocco fans are arranged in series and connected as a side air drive source (air blowing drive source) made of an inexpensive DC fan. The side air speed (wind speed) is increased as much as possible, and even in the case of cardboard or coated paper (coated paper, etc.), it can be surely separated one by one (claims 4-7, 10-12). ).

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments including the best mode and examples for carrying out the present invention will be described below with reference to the drawings. Regarding the constituent elements such as members and components having the same function over the above-described background art examples, embodiments and modifications, etc., once described by attaching the same reference numerals as much as possible, the description will be given. Omitted. In order to simplify the drawings and the description, even components that are to be represented in the drawings may be omitted as appropriate without being specifically described in the drawings.

First, an overall configuration of a digital thermal stencil printing apparatus as an example of a printing apparatus to which the present invention is applied will be described with reference to FIGS. FIG. 9 schematically shows the overall configuration of the digital thermosensitive stencil printing apparatus, and FIG. 10 mainly shows the overall configuration of the stencil printing apparatus main body 200 in FIG.
The stencil printing apparatus shown in FIGS. 9 and 10 can use an active energy ray curable ink. Therefore, an active energy ray curable fixing device 201 for curing the active energy ray curable ink is shown in FIG. It is provided on the paper discharge side of the stencil printing machine main body. As an example of the active energy ray curable ink, an ultraviolet curable ink is used. As an example of the active energy ray curable fixing device, an ultraviolet curable fixing device is used.

9 and 10, a paper feeding unit 110 is provided on the right side of the stencil printing apparatus main body 200. As described above, the active energy ray curing and fixing device 201 is provided on the paper discharge side of the stencil printing apparatus main body 200. In this active energy ray curable fixing device 201, an active energy ray lamp, a motor for conveying paper, a belt, an adsorption fan, and the like are incorporated. Then, the active energy ray curable fixing device 201 is configured to fix the active energy ray curable ink onto the paper and discharge the printed and fixed paper to the paper discharge tray 52 by belt and suction conveyance.
The internal configuration of the active energy ray curable fixing device 201 is the same as the UV irradiation device (2) as the ultraviolet irradiation device shown in FIG. 1 of JP-A-2006-281658 proposed by the present applicant, for example. In relation to this, on the stencil printing apparatus main body 200 side shown in FIG. 10, the same configuration as the stencil printing control apparatus (55) described in FIG. 4 of the above Japanese Patent Laid-Open No. 2006-281658 is arranged. Has been.

Next, the overall configuration of the stencil printing apparatus main body 200 will be described with reference to FIG. In FIG. 10, reference numeral 50 denotes an apparatus main body forming a framework on the stencil printing apparatus main body 200 side. As shown in the figure, the portion indicated by 80 at the top of the apparatus body 50 is a document reading portion as a document reading device, and the portion indicated by 100 below is a plate making portion as a digital thermal stencil type plate making device. The part indicated by 129 on the left side of the plate making unit 100 is a printing drum unit as a printing drum device in which a printing drum 121 having a porous cylindrical plate cylinder on the outer peripheral part is disposed, and a portion 120 below the printing drum 121. A portion shown is a printing pressure unit as a printing pressure device, a portion indicated by 70 on the left side of the printing drum 121 is a plate discharging portion as a plate discharging device, and a portion indicated by 110 below the plate making unit 100 is a paper feeding device as a paper feeding device. The part indicated by the reference numeral 130 on the left side of the printing pressure device 120 and below the plate discharging device 70 indicates a paper discharge unit as a paper discharge device.
9 and 10, reference numerals 150 to 156 shown in parentheses together with the reference numerals of the stencil printing apparatus main body 200 are a first embodiment, a first modification, a second modification, and a second embodiment, which will be described later. These represent the stencil printing apparatus main body according to the third modification, the fourth modification, and the fifth modification, and are distinguished from the stencil printing apparatus main body 200 to which the present invention is applied.

  The document reading unit 80 has a function of reading an image of the surface of the document 60 transferred from a document placing table (not shown), and the plate making unit 100 has a function of making a plate 101 of a master 101 wound in a roll shape and feeding and feeding it. The printing drum unit 129 has a function of winding the plate-making master 101 around the outer peripheral surface thereof and supplying ink to the plate-making master 101 on the printing drum 121. A function of forming a print image on the sheet S by pressing the sheet S as a sheet-shaped recording medium / printing medium against the sheet 121, and the plate discharging unit 70 uses the master 101 from the outer peripheral surface of the printing drum 121 The paper feed unit 110 has a function of stripping and discharging it into the plate discharge box 74. The paper feed unit 110 is configured to print the paper S stacked on the paper feed tray 51 as a paper feed table and the printing drum unit 129 and the printing pressure unit. The ability to feed between 20, sheet ejection section 130, a function of discharging the paper S printed by the printing drum 129 and the indicia pressure part 120 to the discharge tray 52, each having.

  The basic overall operation of the stencil printing apparatus main body will be described with reference to FIGS. First, the user places and sets a document 60 having an image to be printed on a document placing table (not shown) disposed at the top of the document reading unit 80, and makes a plate making start key 91 on the operation panel 90 shown in FIG. Press. In response to pressing of the plate making start key 91, a plate making start signal is generated, and this is used as a trigger to first execute the plate discharging process. That is, in this state, the used master 101 used in the previous printing remains attached to the outer peripheral surface of the printing drum 121 (the outer peripheral surface of the plate cylinder). The printing drum 121 is connected to printing drum driving means (not shown, for example, a main motor) via a driving mechanism (not shown), and is driven to rotate by the printing drum driving means.

  The printing drum 121 rotates in the direction opposite to the arrow direction A in the figure, and the rear end portion of the used master 101 mounted on the outer peripheral surface of the printing drum 121 approaches the pair of plate discharge peeling rollers 71 a and 71 b of the plate discharge unit 70. Then, the roller pair 71a, 71b rotates while scooping up the rear end of the used master 101 with one of the plate release roller 71b, and a plate discharge roller pair 73a disposed to the left of the plate release roller pair 71a, 71b. , 73b and a pair of discharge plate transfer belts 72a and 72b spanned between the pair of discharge plate peeling rollers 71a and 71b, the used master 101 is gradually peeled off from the outer peripheral surface of the printing drum 121. Then, the sheet is discharged into the discharge plate box 74 while being conveyed in the arrow direction X1, and the so-called discharge process is completed. At this time, the printing drum 121 continues to rotate counterclockwise. The used master 101 that has been discharged is then compressed inside the discharge plate box 74 by the compression plate 75.

In parallel with the plate removal process, the document reading unit 80 operates to read the document. In other words, the document 60 placed on a document placement table (not shown) is moved in the direction of arrows X2 to X3 (hereinafter referred to as the following) by the rotation of the separation roller 81, the front document transport roller pair 82a, 82b, and the rear document transport roller pair 83a, 83b. (Referred to as “original transport direction X2”) while being conveyed for exposure reading. At this time, when there are a large number of documents 60, only the lowermost document is conveyed by the action of the separating blade 84.
The upper rear document transport roller 83a is rotationally driven by a document transport motor (not shown) made of, for example, a stepping motor. The upper front document transport roller 82a is rotationally driven by the document transport motor via a timing belt (not shown) spanned between the upper transport roller 83a and the transport roller 82a, and each roller 82b, 83b. Each follower rotation.

  When reading the image of the original 60, the reflected light from the surface of the original 60 illuminated by the fluorescent lamp 86 while being conveyed on the contact glass 85 is reflected by the mirror 87 and passes through the lens 88, and then the CCD (photocoupler such as a charge coupled device) is read. This is performed by being incident on an image sensor 89 formed of a conversion element. The original 60 from which the image has been read is discharged onto the original tray 80A.

  Optical information (image data) of the document 60 is photoelectrically converted by the image sensor 89, and an analog electric signal is input to an analog / digital (A / D) converter (not shown) and converted into a digital image signal. . This digital image signal is subjected to image processing for stencil printing by an image processing unit (not shown) in a control unit (not shown). Digital image signals relating to binary black pixels and white pixels thus subjected to image processing are It is input to a thermal head drive control unit (not shown). This thermal head drive control unit controls each heating element 102a of the thermal head 102 shown in FIG. 10 mainly through a thermal head drive circuit (not shown), and receives a command from a control means (not shown). Control operation.

The optical information (image data) input to the A / D conversion unit is not limited to that read by the CCD, and may be information from a contact image sensor (CIS) or the like, for example. The digital image data input to the thermal head drive control unit in the control unit (not shown) may be a digital image signal transmitted from a computer such as a personal computer.
The digital image signal input to the thermal head drive control unit in the control unit (not shown) generates a digital image data signal or the like as a thermal head drive signal and passes through a thermal head drive circuit (not shown). 102.

On the other hand, in parallel with such document scanning and image reading operations, plate making and plate feeding processes are performed based on digital signalized image information (digital image signal). That is, when the plate making start signal is used as a trigger and a stepping motor (not shown) coupled to the platen roller 103 is driven to rotate, the master 101 is set to be able to be fed out via a master support member (not shown). The master 101 is pulled out from a master roll 101A formed by being wound around the core tube 101a. At this time, the master 101 performs sub-scanning indicated by an arrow X4 in the drawing by rotation at a constant speed of the platen roller 103 and the tension roller pair 105a, 105b serving as a master conveying unit pressed against the thermal head 102 via the master 101. It is transported downstream in the direction X4 (hereinafter also referred to as “master transport direction X4”).
A large number of minute heating elements 102a arranged in a line in the main scanning direction of the thermal head 102 are sent from the thermal head drive control unit in the control unit (not shown) to the conveyed master 101. Each position-selective heat is generated according to the digital image data signal, and the film portion of the master 101 that is in contact with the heat generating element 102a is heated, melted and punched. In this way, image information is written in the master 101 as a drilling pattern by position-selective melt drilling of the master 101 according to the image information.

  The platen roller 103 is connected to a stepping motor (not shown) via a rotation transmission member (not shown) such as a timing belt and a gear, and is rotated by the stepping motor. The rotational driving force of the stepping motor is applied to a pair of upper and lower reversing rollers 107a and 107b via a rotation transmission member (not shown) such as a gear and via a tension roller pair 105a and 105b and an electromagnetic clutch (not shown). It is to be transmitted. In addition, there is a device in which a stepping motor different from the stepping motor for rotating the driving roller of the pair of reverse rollers 107a and 107b is provided instead of the electromagnetic clutch.

  The thermal head 102 is shown for receiving a digital image signal from the image sensor 89, the A / D conversion unit, the image processing unit, etc. (not shown) or from a personal computer (not shown) as described above. Thermal head drive including digital image data signal processed and sent out by the thermal head drive control unit of the control unit (not shown) via the image processing unit via the personal computer / controller, interface device, data development unit, etc. The master 101 has a function as plate-making means for position-selectively heating, melting, punching, and making a plate by selectively heating a large number of heating elements 102a based on the signal for use. The thermal head 102 can be brought into and out of contact with the platen roller 103 via the master 101 by a well-known contacting / separating means (not shown).

As the master 101 used in FIGS. 9 and 10, for example, a laminate structure in which a thermoplastic resin film and a porous support made of Japanese paper fiber or synthetic fiber or a mixture of Japanese paper fiber and synthetic fiber are bonded together. Can be mentioned. As the thermoplastic resin film, for example, a polyethylene terephthalate (PET) film is used.
In FIG. 10, 65, 66, 76, 77 and 78 indicated by two-dot chain lines indicate control means according to Modifications 1 and 2 of the first embodiment and Modifications 3 to 5 of the second embodiment which will be described later. In the same figure, 67 shown with a dashed-two dotted line represents the temperature detection sensor as a temperature detection means which detects the temperature inside the stencil printing apparatus main bodies 150-156,200, respectively. As described above, the control means 65 and 66 and the temperature detection sensor 67 are used in Modification 2 of the first embodiment and Modification 4 of the second embodiment, which will be described later. This is shown in FIG.
The plate making unit 100 constitutes a plate making unit that can be attached to and detached from the apparatus main body 50 via a known attaching / detaching means. As the attaching / detaching means, for example, a guide member having a U-shaped cross section that is provided on the apparatus main body 50 side and guides the plate making unit, and a convex member that is provided on the plate making unit side and is slidable with respect to the guide member. Combinations are mentioned. As described above, since a guide member (not shown) and the like is disposed on the apparatus main body 50 side, space saving and miniaturization in the height direction Z in the paper feeding unit 110A are desired.

The leading end of the master 101 having image information written therein is fed toward the outer periphery of the plate cylinder of the printing drum 121 by the pair of reverse rollers 107a and 107b, and the traveling direction is changed downward by the plate feeding guide plate 108. Then, it hangs down toward the master clamper 122 in which the printing drum 121 in the plate feeding position state indicated by a two-dot chain line in FIG. At this time, the used master 101 has already been removed from the printing drum 121 by the plate discharging process.
When the leading end of the master 101 that has been made is clamped and held by the master clamper 122 at a fixed timing by the operation of an opening / closing device (not shown) disposed on the apparatus main body 50 side to open and close the master clamper 122, the printing drum 121. , The master 101 that has been subjected to the plate making is gradually wound around the outer peripheral surface while rotating in the arrow A direction (clockwise direction) in the figure. The plate making master 101 has its rear end cut into a certain length by the cutter 104 after the plate making is completed, and the plate making master 101 is completely wound around the outer peripheral surface of the printing drum 121. The plate making and feeding processes are completed.

  After that, the rotation of the platen roller 103, the pair of tension rollers 105a and 105b, and the pair of reverse rollers 107a and 107b causes the upstream end of the remaining master 101 on the upstream side to be transported toward the nip portion of the pair of reverse rollers 107a and 107b. The When the leading edge of the master 101 thus transported is detected by a master leading edge detection sensor (not shown) and it is determined that the leading edge of the master 101 has occupied the initial position, the platen roller 103, the tension roller pairs 105a and 105b, and the reverse roller pair 107a, The rotation of 107b stops, and a plate making standby state for the next plate making is entered. The initial position of the master 101 is set in advance, for example, to a position slightly protruding forward from the position sandwiched between the nip portions of the pair of reversing rollers 107a and 107b.

  Next, the printing process is started. First, the uppermost one of the sheets S stacked on the sheet feeding tray 51 is pulled out by the sheet feeding roller 111 and further separated into one sheet by the cooperative action of the separation roller pairs 112a and 112b. The printing drum 121 in the printing pressure unit 120 is fed to the roller pair 113a, 113b in the direction of arrow X (paper conveyance direction X) and is further synchronized with the rotation of the printing drum 121 by the registration roller pair 113a, 113b. And the press roller 123. The press roller 123 is detachably contacted with the outer peripheral surface of the printing drum 121 by a known press roller displacing means (not shown), and is supplied to the printing drum 121 on which the master 101 having been made on the outer peripheral surface is wound. It functions as a pressing unit that presses the fed paper S to form a print image on the paper S. When the fed paper S is inserted between the printing drum 121 and the press roller 123, the press roller 123 that has been separated below the outer peripheral surface of the printing drum 121 is swung and raised. As a result, it is pressed against the master 101 that has been pre-rolled around the outer peripheral surface of the printing drum 121. Thus, due to the adhesive force due to the viscosity of the ink that has oozed out from the porous portion of the printing drum 121, the master 101 that has been subjected to plate making comes into close contact with the outer peripheral surface of the printing drum 121, and at the same Ooze out and the oozed ink is transferred to the surface of the paper S to form a printed image.

At this time, ink is supplied to the ink reservoir 127 formed between the ink roller 125 and the doctor roller 126 from the ink supply pipe 124 that also serves as the support shaft 124 on the inner peripheral side of the printing drum 121, and the rotation of the printing drum 121. Ink is supplied to the inner peripheral side of the printing drum 121 by the ink roller 125 that is in contact with the inner peripheral surface while rotating in the same direction as that of the printing drum 121 in synchronization with the rotation speed of the printing drum 121.
The ink supply pipe 124, the ink roller 125, and the doctor roller 126 constitute an ink supply unit that supplies ink to the master 101 on the printing drum 121. The pressing means is not limited to the press roller 123, and an impression cylinder having a diameter substantially the same as the diameter of the printing drum (plate cylinder) 121 is also used. Of course, the present invention is applied to such an impression cylinder type stencil printing apparatus. The
As described above, the printing drum 121, the ink supply unit, and the press roller 123 constitute a print image forming unit that forms a print image using ink on the paper S fed by the printing unit 110.

  For example, W / O type emulsion ink is preferably used as the ink used when printing on uncoated paper such as high-quality paper. Hereinafter, in the example of the stencil printing apparatus shown in FIG. 9 and FIG. 10, it is assumed that an ultraviolet curable ink as an active energy ray curable ink is used in order to simplify the description. Hereinafter, the simple ink means an active energy ray curable ink (ultraviolet curable ink).

The sheet S on which the printing image is formed in the printing pressure unit 120 is peeled off from the print drum 121 by the sheet discharge peeling claw 114 in the sheet discharge unit 130 and is sucked by the suction fan 118 while being sucked by the suction sheet discharge inlet roller 115 and the suction. It is adsorbed by the porous conveyance belt 117 stretched around the sheet discharge outlet roller 116, and is conveyed toward the sheet discharge table 52 as indicated by the arrow X5 by the rotation and running of the conveyance belt 117 in the counterclockwise direction. The paper is sequentially discharged and stacked on the paper discharge tray 52. In this way, so-called plate printing is completed.
After the plate printing is completed, the press roller 123 is separated from the printing drum 121, and the printing drum 121 returns to the initial position (home position) where the master clamper 122 is substantially above in FIG.

  Next, a desired printing speed value is set by pressing a printing speed setting key (not shown) arranged on the operation panel 90 shown in FIG. When the print start key 92 is pressed and the printing start key 92 is pressed, the paper feeding, printing, and paper ejection steps are repeated for the set number of prints at the set printing speed in the same process as the stencil printing. This completes the entire process.

In FIG. 10, a portion surrounded by a two-dot chain line except for the registration roller pairs 113a and 113b is a paper feed configured to be detachably attached to the apparatus main body 50 via an attaching / detaching means including a fastening means such as a screw (not shown). The unit 110A is shown. The sheet feeding unit 110A is configured as a sheet feeding device using the friction method described above. In the paper feeding unit 110A, the separation roller pairs 112 and 112b are used as the separating means, but a combination of a paper feeding roller and a friction pad as a friction member is also used.
In FIG. 10, reference numerals 1A and 1B indicated by parentheses together with the reference numeral of the paper feeding unit 110A are described later, which are configured to be detachable from the apparatus main body 50 through attachment / detachment means including fastening means such as screws (not shown). 2 shows a sheet feeding unit according to the first and second embodiments.
Further, the air feeding device may be configured so as to be mounted as an external option on the printing apparatus main body in combination with a mass feeding unit capable of mass feeding.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS.
Compared with the paper feeding unit 500A of the air paper feeding device 500 shown in FIGS. 6 and 7, the first embodiment shows the air paper feeding device 1 as shown in FIG. 1 and FIG. The only difference is that the sheet feeding unit 1A is used. The paper feeding unit 1A of the air paper feeding device 1 is different from the paper feeding unit 500A of the air paper feeding device 500 only in using a suction unit 10A instead of the suction unit 10 of the paper feeding unit 500A.
As compared with the suction unit 10 shown in FIGS. 6 and 7, the suction unit 10 </ b> A replaces the air suction drive fan 15 with a plurality of air suction drive sources (this embodiment) as shown in FIGS. 1 and 2. In the example, it is clearly stated that two sirocco fans 15a and 15b are used, that is, a sirocco fan 15a having an air suction port 15a1 for sucking air and an air discharge port 15a2 for discharging air, and air for sucking air Next to the air discharge port 15a2 of the sirocco fan 15a upstream of the air discharge path (air flow direction), it is clearly stated that the sirocco fan 15b having the suction port 15b1 and the air discharge port 15b2 for discharging air is used. The main difference is that the air suction port 15b1 of the downstream sirocco fan 15b is connected and connected.
The air sheet feeder 1 of the first embodiment is the same as the air sheet feeder 500 shown in FIGS. 6 and 7 except for the above differences. 9 and 10, the air-type paper feed unit 1A shown in parentheses together with the friction-type paper feed unit 110A is mounted and applied to the stencil printing apparatus shown in the figure instead of the paper feed unit 110A. Represents.

As a method of increasing the static pressure even in a DC fan, air suction drive fans as air suction drive sources are sirocco fans 15a and 15b, and the sirocco fans 15a and 15b are arranged as shown in both drawings. That is, after the suction drive source chamber 17 is connected to and connected to the suction relay pipe (duct) 13 in the same manner as shown in FIGS. 6 and 7, the upstream side of the suction drive source chamber 17 is upstream as shown in FIGS. The air suction port 15a1 of the sirocco fan 15a is connected and connected.
A fan connection duct 45 is connected to and connected to the air discharge port 15a2 of the upstream sirocco fan 15a, and then a fan connection duct 45 is connected to and connected to the air suction port 15b1 of the downstream sirocco fan 15b. The air discharge port 15b2 of the sirocco fan 15b is opened on the most downstream side so as to discharge air. In other words, two sirocco fans 15a and 15b are connected and connected in series.
As a matter of course, the connection portion between the suction relay pipe 13 and the suction drive source chamber 17, the connection portion between the suction drive source chamber 17 and the air suction port 15a1 of the sirocco fan 15a, and the fan connection with the air discharge port 15a2 of the sirocco fan 15a. The connection part between the duct 45 and the connection part between the air suction port 15b1 of the sirocco fan 15b and the fan connection duct 45 has an appropriate fitting connection shape so that there is no air leakage, and an appropriate seal tape or the like is applied. Thus, air leakage is prevented.

FIG. 3 shows a specific product example of the sirocco fans 15a and 15b. In FIG. 3, 15c denotes a multi-blade fan provided in the sirocco fans 15a and 15b, and 15d denotes a lead wire for supplying electric power to the DC fan motor provided in the sirocco fans 15a and 15b. The name of the sirocco fan is a term widely used among those skilled in the art, but its official name (academic term) corresponds to a multiblade fan of a centrifugal blower.
As is well known, a centrifugal blower (sirocco fan) equipped with a multi-blade fan is small and inexpensive, and it is easy to obtain a large pressure increase in one stage and less noise than an axial flow blower. There is a feature.

The sirocco fans 15a and 15b have the same static pressure specifications, that is, have the same shape and dimensions including the static pressure specifications. By adopting a configuration in which the two sirocco fans 15a and 15b are communicated and connected in series, the static pressure can be increased by about 50% compared to the case of one of the sirocco fans 15a and 15b. For example, assuming that the static pressure of one sirocco fan is 400 Pa, only one of the sirocco fans 15a and 15b and the sirocco fans 15a and 15b connected in series as shown in FIGS. As a result of conducting a comparison test with the configuration, it was possible to increase about 50% to 600 Pa in this embodiment.
In general, when two sirocco fans having the same static pressure specifications are connected and connected in series, the theoretical static pressure is doubled, but in this embodiment, the suction drive source chamber 17 and the fan are connected. It was found that the friction was increased by about 50% due to friction and load resistance caused by the duct 45.
In this embodiment, since each sirocco fan 15a, 15b consists of DC fans, it is also possible to change a static pressure and an air volume by changing each rotation speed, However, In this embodiment, normally, Each sirocco fan 15a, 15b is set to be driven to rotate at the maximum rotational speed.

1 and 2, the suction belt 11, the drive roller 14a, the driven roller 14b, and the suction chamber 12 (shown in FIGS. 6 and 7 and not shown in FIGS. 1 and 2), the suction relay pipe 13, and the suction drive The source chamber 17, the sirocco fans 15a and 15b, the fan connection duct 45, and the suction belt drive motor 47 (shown in FIGS. 6 and 7 and not shown in FIGS. 1 and 2) constitute the suction unit 10A. Yes.
In the suction unit 10A, the suction belt 11, the suction chamber 12 (shown in FIGS. 6 and 7 and not shown in FIGS. 1 and 2), the suction relay pipe 13, the suction drive source chamber 17, and each sirocco fan 15a. , 15b constitute air suction means.
In the suction unit 10, the suction belt 11, the drive roller 14a, the driven roller 14b, and the suction belt drive motor 47 constitute sheet feeding means for feeding the paper S sucked and held by the air suction means. is doing.

  According to the present embodiment, in the paper feeding unit 1A of the air paper feeding device 1 and the stencil printing apparatus main body 150 having the same, the suction of the apparatus main body 50 in order to save space and reduce the size in the height direction Z. Even when the pitch between the belts 11 is small or the diameter of the driving (driven) roller 14a (14b) is small, the sirocco fans 15a and 15b, which are inexpensive DC fans, are connected and connected in series as described above. As a result, the sheet S can be sufficiently sucked and held and fed by increasing the static pressure.

(Modification 1 of the first embodiment)
With reference to FIG. 4 and FIG. 10, the modification 1 of 1st Embodiment is demonstrated.
In the first modification, instead of the paper feeding unit 1A of the air paper feeding device 1 according to the first embodiment and the stencil printing apparatus main body 150 having the same, as shown in FIGS. The main difference is that a stencil printing apparatus main body 151 having a paper type setting means and a control means 65 as a paper type recognition means provided in FIG. The first modification is the same as the first embodiment except for the above differences, and it is needless to say that the first modification includes the same sheet feeding unit 1A of the air sheet feeding apparatus 1 as that of the first embodiment. is there.

An operation panel 90 shown in FIG. 11 is arranged on one side of the upper part of the document reading unit 80. As shown in detail in FIG. 11, the operation panel 90 includes a plate making start key 91, a printing start key 92, a numeric keypad 93, a trial printing key 94, an enter key 95, a mode clear key 96, a touch panel 98, a display device 99, and the like. It is installed. The operation panel 90 is also provided with a function that functions as a paper type setting unit as a notification type and a sheet type recognition unit that recognizes the sheet type.
The plate making start key 91 functions as an operation starting means for starting a series of steps (operations) from reading of an image of a document to plate discharge, plate making, plate feeding, paper feeding, plate printing, and paper discharge steps. The numeric keypad 93 has a function for inputting and setting the number of prints and the like, the print start key 92 has a function for starting the printing operation for the number of prints inputted and set with the numeric keys 93, and the trial printing key 94 has Each has a function of starting a test printing operation. The enter key 95 has a function for confirming / setting values and the like at various settings, and the mode clear key 96 has a function for erasing / clearing various mode setting states. Is done.

The touch panel 98 is driven by an LCD (Liquid Crystal Display) drive circuit including a touch panel drive circuit (not shown), and is used to display various modes and various selection setting means (the above-described paper type setting means) displayed on the screen by a known touch panel method. It is configured so that it can be highlighted and selected and set.
The display means or notification means comprising an LCD screen disposed on the touch panel 98 is used when the ink used and the air volume due to the rotational speed of each sirocco fan 15a, 15b do not match the thin paper, plain paper, coated paper or cardboard. This is displayed or notified.
The paper type setting means has a function as a paper type recognition means capable of selecting and setting thin paper, plain paper, coated paper, and thick paper as the paper, and specifically, a thin paper setting key provided on the touch panel 98. 131, a plain paper setting key 132, a coated paper setting key 133, and a thick paper setting key 134. The paper type setting means is not limited to the one described above, and a key capable of setting thick paper or the like in more detail may be provided.

  Not only the above paper type setting means, but also known paper (sheet / printing medium) type detection by detecting and recognizing the amount of reflected light on each surface of thin paper, plain paper, coated paper and thick paper using the difference in smoothness It may be paper (sheet / print medium) type recognition means including means. As the paper type detection means, for example, the same paper type detection sensor (40) as shown in FIG. 5 of JP-A-2001-328332 can be used. That is, the paper type detection means is described in paragraph numbers “0059” to “0065” of the above publication, and as shown in detail in FIG. 5, a light emitting element as light emitting means for projecting light onto the surface of the paper 62 A light emitting section (40a) having (40aa) and a light receiving section (40b) having a plurality of light receiving elements (40ba) as light receiving means for receiving reflected light reflected by the surface of the paper 62, The light-emitting unit (40a) and the light-receiving unit (40b) receive the reflected light received by the plurality of light-receiving elements (40ba) of the light-receiving unit (40b) with respect to the sheet 62 that is moved by being conveyed. The type of printing medium is automatically detected by recognizing the variation. Further, it may detect thin paper, plain paper, coated paper, or thick paper by detecting the amount of transmitted laser light. The sheet type recognition unit includes both a sheet type setting unit and a sheet type detection unit.

The control unit 65 selects one of the paper types from the thin paper setting key 131, the plain paper setting key 132, the coated paper setting key 133, and the thick paper setting key 134 selected and set by the paper type setting unit as the sheet type recognition unit. Accordingly, the sirocco fans 15a and 15b have a function of controlling to change the rotation speed and the air volume.
The control means 65 is based on signals from various keys and switches and various sensors arranged on the operation panel 90, a liquid crystal display device (LCD) and various LEDs arranged on the operation panel 90, and each of the above devices and parts. (Not shown) each having a known microcomputer equipped with a CPU, ROM, RAM, timer, etc. (control means 66 of modification 2 described later, control means 76 of modification 3 and modification) The same applies to the control means 77 of Example 4 and the control means 78 of Modification 5.) In the ROM, an operation program and related data for performing the function of the CPU of the control means 65 are stored in advance (control means 66 of Modification 2 described later, control means 76 of Modification 3 and Modification 4). The same applies to the control means 77 and the control means 78 of the modified example 5).

As described in the first embodiment, each sirocco fan 15a, 15b is normally driven to rotate at the maximum number of rotations. However, in the case of thin paper or the like that has no waist, if the static pressure is high, the paper may enter the hole 11a of the suction belt 11 and damage the paper. In that case, according to a command from the control means 65, the rotational speed of one of the sirocco fans 15a, 15b is halved or stopped so that static pressure is applied so as not to damage the thin paper (paper). Can be lowered.
That is, according to the first modification, the same effect as that of the first embodiment can be obtained, and when the thin paper is used on the operation panel 90, the thin paper setting key 131 for setting the thin paper mode is pressed. The rotational speed of one fan can be automatically reduced by the control by the control means 65.

  In the first modification, the control unit 65 and the sheet type recognizing unit are described on the stencil printing apparatus main body 151 side. However, the present invention is not limited thereto, and the control unit 65 and the sheet type recognizing unit are not limited to the sheet feeding device. The air feeding device 1 can be arranged on the paper feeding unit 1A side. According to a configuration conceptually expressing this, that is, in the sheet feeding device according to claim 3, according to the sheet type recognizing unit for recognizing the type of the sheet, and the sheet type recognized by the sheet type recognizing unit. A sheet feeding apparatus having control means for controlling each sirocco fan may be used.

(Modification 2 of the first embodiment)
A modification 2 of the first embodiment will be described with reference to FIGS. 5 and 10.
In the second modification, instead of the paper feeding unit 1A of the air paper feeding device 1 and the stencil printing apparatus main body 150 having the same in the first embodiment, as shown in FIGS. Mainly, a stencil printing apparatus main body 152 having a paper type setting means as a paper type recognition means provided in the apparatus, a temperature sensor 67 made of, for example, a thermistor disposed in the apparatus main body, and a control means 66 is used. Is different. The second modification is the same as the first embodiment except for the above differences, and it is needless to say that the second modification has the same paper feeding unit 1A as that of the first embodiment. is there.

  The control unit 66 selects any one paper type from the thin paper setting key 131, the plain paper setting key 132, the coated paper setting key 133, and the thick paper setting key 134 selected and set by the paper type setting unit as the sheet type recognition unit. In accordance with the temperature in the apparatus main body 50 detected by the temperature sensor 67, the sirocco fans 15a and 15b have a function of controlling the rotational speed and the air volume to be changed.

In the second modification, in addition to the control peculiar to the first modification by the control means 65, there is a possibility that the sheet such as thin paper may be further damaged at the time of high temperature and high humidity. Therefore, in the second modification, the same effect as that of the first embodiment is obtained. When using thin paper, the thin paper mode is set by pressing the thin paper setting key 131 for setting the thin paper mode, and the temperature is set. When the temperature from the sensor 67 is higher than the temperature stored in the ROM (not shown) in advance, the operation of one fan is automatically stopped by the control of the control means 66, and the thin paper (paper) is damaged. It can be lowered to an appropriate static pressure only by the other fan.
In addition, when it is desired to detect a high temperature and high humidity state more accurately, a known temperature / humidity sensor in which a temperature sensor and a humidity sensor as temperature / humidity detection means are integrated may be employed.

  In the second modification, the control unit 66, the sheet type recognition unit, and the temperature sensor 67 as the temperature detection unit have been described as being disposed on the stencil printing apparatus main body 152 side. The temperature sensor 67 as the type recognizing unit and the temperature detecting unit may be arranged on the sheet feeding unit 1A side in the air sheet feeding device 1 as the sheet feeding device. A configuration that expresses this conceptually, that is, in the sheet feeding device according to claim 3, a sheet type recognition unit that recognizes the type of the sheet, a temperature detection unit that detects the temperature of the sheet feeding device, A sheet feeding device having control means for controlling each sirocco fan in accordance with the sheet type recognized by the sheet type recognition means and the temperature of the sheet feeding device detected by the temperature detection means. May be.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. 12 and 14, the length in the paper transport direction X in the paper feed tray 3 and the paper bundle 2 on the paper feed tray 3 is shown exaggerated in the paper transport direction X. Further, in FIG. 14, illustration of the back side of the paper surface of the sirocco fans 15 a and 15 b and the side discharge relay rod 43 is omitted for simplification of the drawing.
Compared with the paper feeding unit 1A of the air paper feeding device 1 in the first embodiment shown in FIGS. 1 to 3, the second embodiment is an air paper feeding device as shown in FIGS. The only difference is that one sheet feeding unit 1B is used. Compared with the paper feed unit 1A of the air paper feeder 1 of the first embodiment, the paper feed unit 1B uses a side discharge unit 40A instead of the side discharge unit 40, and this side discharge unit 40A is adopted. Accordingly, the difference is that the air blowing drive source and the like constituting this are configured in a specific arrangement as will be described later.

The front discharge unit composed of the front discharge chamber 20 and the front air discharge fan 23, and the side discharge unit 40A, the sheet S by blowing air a to the leading end surface and both end surfaces of the sheet bundle 2 stacked on the sheet feeding tray 3. Air separation means for separating the sheets one by one is configured. The present embodiment focuses particularly on the side discharge unit 40A in the configuration of the air separation means.
The paper feeding unit 1B of the air paper feeding device 1 is the same as the paper feeding unit 1A of the air paper feeding device 1 in the first embodiment shown in FIGS. 1 to 3 except that the above differences will be described in detail later. is there. In FIG. 9 and FIG. 10, an air-type paper feeding unit 1B shown in parentheses together with the friction-type paper feeding unit 110A is a stencil printing apparatus main body shown in parentheses in the same drawing instead of the paper feeding unit 110A. 153 indicates that it is mounted and applied.

  Compared to the side discharge unit 40 shown in FIG. 7, the side discharge unit 40 </ b> A replaces the side air discharge fan 41 as a side air discharge source, as shown in FIGS. 12 to 15, as an air blowing drive source. A plurality of (two in the present embodiment) air blowing drive source sirocco fans 41a and 41b (hereinafter also simply referred to as “sirocco fans 41a and 41b”), that is, air blowing drive source air that sucks air. A sirocco fan 41a having a suction port 41a1 (hereinafter also simply referred to as “air suction port 41a1”) and an air blowing drive source air discharge port 41a2 (hereinafter also simply referred to as “air discharge port 41a2”) for discharging air. And air blowing port 41b1 for air blowing drive source (hereinafter also simply referred to as “air suction port 41b1”) for sucking air and air blowing for discharging air The point of using a sirocco fan 41b provided with a power source air discharge port 41b2 (hereinafter also simply referred to as “air discharge port 41b2”), an air discharge port of the sirocco fan 41b upstream of the air discharge path (air flow direction) 41b2 is mainly different in that the air suction port 41a1 of the adjacent downstream sirocco fan 41a is communicated and connected.

  As a method of increasing the static pressure even in a DC fan, air blowing drive fans as air blowing drive sources are sirocco fans 41a and 41b, and the sirocco fans 41a and 41b are arranged as shown in FIGS. That is, the fan connection duct 46 is communicated and connected to the air discharge port 41b2 of the upstream sirocco fan 41b, and the fan connection duct 46 is communicated and connected to the air suction port 41a1 of the downstream sirocco fan 41a. The air discharge port 41a2 of the sirocco fan 41a is opened on the most downstream side so that air is pumped and discharged. In other words, two sirocco fans 41a and 41b are connected and connected in series.

  A side discharge drive source chamber 44 communicates with and is connected to the air discharge port 41a2 of the sirocco fan 41a, and side discharge relay pipes (ducts) extending in the paper width direction Y on both sides of the side discharge drive source chamber 44. ) 43 is connected and connected. The side discharge relay pipes 43 are provided so as to extend to the upstream and downstream sides in the paper transport direction X so as to face both end surfaces of the sheet bundle 2 stacked on the paper feed tray 3. Side discharge nozzles 42 a, 42 b, 42 c, 42 d provided with side air discharge ports for blowing and discharging air a to each side end surface of the sheet bundle 2 at the end portions of the side discharge relay pipes 43 on both sides in the sheet width direction Y. Are connected and connected.

  As described above, each side discharge nozzle 42a, 42b, 42c, 42d provided with a side air discharge port communicates with the two sirocco fans 41a, 41b via the side discharge relay pipe 43 and the side discharge drive source chamber 44. It is connected. Therefore, the air a pumped at a high static pressure generated by the two sirocco fans 41a and 41b communicated and connected in series passes through the side discharge drive source chamber 44 and the side discharge relay pipe 43, and is supplied to each side discharge. By ejecting from the nozzles 42a, 42b, 42c, and 42d and spraying each side end surface of the sheet bundle 2, the sheets S are surely separated one by one.

  Naturally, each side discharge nozzle 42a, 42b, 42c, 42d and the connection part of the side discharge relay pipe 43, the connection part of the side discharge relay pipe 43 and the side discharge drive source chamber 44, and the side discharge drive source chamber 44 And the connection part between the air discharge port 41a2 of the sirocco fan 41a, the connection part between the air suction port 41a1 of the sirocco fan 41a and the fan connection duct 46, and the connection part between the fan connection duct 46 and the air discharge port 41b2 of the sirocco fan 41b. In order to prevent air leakage, the air is prevented from leaking by an appropriate fitting connection shape so that there is no air leakage, and by applying an appropriate seal tape or the like.

  As a specific product example of the sirocco fans 41a and 41b, as shown in FIG. 3, it is the same as the sirocco fans 15a and 15b of the first embodiment. 3, 41c indicates a multi-blade fan provided in the sirocco fans 41a and 41b, and 41d indicates a lead wire for supplying power to the DC fan motor provided in the sirocco fans 41a and 41b. .

Each sirocco fan 41a, 41b has the same static pressure specification, that is, has the same shape, dimensions, etc., including the static pressure specification. By adopting a configuration in which the two sirocco fans 41a and 41b are communicated and connected in series, the static pressure can be increased by about 50% compared to the case of either one of the sirocco fans 41a and 41b. For example, assuming that the static pressure of one sirocco fan is 400 Pa, only one of the sirocco fans 41a and 41b and the sirocco fans 41a and 41b are connected in series as shown in FIGS. As a result of conducting a comparison test with the configuration, it was possible to increase about 50% to 600 Pa in this embodiment.
As described above, when two sirocco fans having the same static pressure specifications are connected and connected in series, the theoretical static pressure is doubled, but in this embodiment, the fan connection duct 46, side discharge It was found that the driving source chamber 44 and the side discharge relay pipe 43 increase the friction by about 50% due to friction, load resistance, and the like.

  In the present embodiment, each sirocco fan 41a, 41b is composed of a DC fan. Therefore, it is possible to change the static pressure and the air volume by changing the number of rotations of each sirocco fan 41a, 41b. Each sirocco fan 41a, 41b is set to be driven to rotate at 70% of the maximum rotational speed. That is, when the rated voltage of each sirocco fan 41a, 41b is 24V, for example, it is set to about 17V. In the following description, the rated voltage of each sirocco fan 41a, 41b is set to 24V.

  According to the present embodiment, in the paper feeding unit 1B of the air paper feeding device 1 and the stencil printing apparatus main body 153 having the same, the sirocco fans 41a and 41b, which are inexpensive DC fans, are connected in series as the air blowing drive source as described above. By connecting and connecting to the air, the static pressure is increased as much as possible, so the speed of the side air (wind speed) is increased, especially for thick paper and coated paper (coated paper, etc.) It became possible to separate each sheet.

(Modification 3 of the second embodiment)
A third modification of the second embodiment will be described with reference to FIGS. 10, 11, and 16.
As shown in FIGS. 10, 11, and 16, the modified example 3 is an operation panel 90 instead of the paper feeding unit 1 </ b> B of the air paper feeding device 1 of the second embodiment and the stencil printing apparatus main body 153 having the same. The main difference is that a stencil printing apparatus main body 154 having a paper type setting means as a paper type recognizing means and a control means 76 is used. The third modification is the same as the second embodiment except for the above differences, and it is needless to say that the modification 3 includes the same paper feeding unit 1B of the air feeding device 1 as that of the second embodiment. is there.

  The control unit 76 selects one of the paper types from the thin paper setting key 131, the plain paper setting key 132, the coated paper setting key 133, and the thick paper setting key 134 which is selected and set by the paper type setting unit as the sheet type recognition unit. Accordingly, the sirocco fans 41a and 41b have a function of controlling the rotational speed and the air volume to be changed.

As described in the second embodiment, each sirocco fan 41a, 41b is normally set to be driven to rotate at 70% of the maximum rotation speed. However, when using thin paper or other thin paper, if the side air speed (wind speed) is high, the paper S on the paper bundle 2 made of thin paper or the like is blown up more than necessary, or the paper S is fluttered. Thus, the suction belt 11 on the suction unit 10A side cannot easily suck the uppermost sheet S1, and a conveyance error may occur.
In that case, the rotational speed of both sirocco fans 41a and 41b is automatically slowed down (for example, fan voltage 14V) or one of the sirocco fans 41a and 41b is stopped by a command from the control means 76.
Further, in the case of using thick paper, it is better to increase the speed of the side air (wind speed) in order to reliably separate the sheets S on the paper bundle 2 made of thick paper one by one. In that case, the rotational speed of both the sirocco fans 41a and 41b is automatically increased by a command from the control means 76 (fan voltage of about 21V).

  That is, according to the third modification, the same effect as that of the second embodiment can be obtained, and when the thin paper is used, the thin paper setting key 131 for setting the thin paper mode is pressed on the operation panel 90. The speed of the side air (wind speed) is reduced by automatically slowing down the rotational speeds of both the sirocco fans 41a and 41b (for example, fan voltage 14V) or stopping one of the sirocco fans 41a and 41b by the control by the control means 76. Can be late. Further, when using thick paper, the rotational speed of both sirocco fans 41a and 41b is automatically increased (fan voltage 21V) by the control of the control means 76 by pressing the thick paper setting key 134 on the operation panel 90. Can do.

  In the third modification, the control unit 76 and the sheet type recognition unit are described as being disposed on the stencil printing apparatus main body 153 side. However, the present invention is not limited thereto, and the control unit 76 and the sheet type recognition unit are not limited to the sheet feeding device. The air feeding device 1 can be arranged on the paper feeding unit 1B side. According to a configuration in which this is expressed conceptually, that is, in the sheet feeding apparatus according to claim 6, according to the sheet type recognizing means for recognizing the sheet type and the sheet type recognized by the sheet type recognizing means. A sheet feeding apparatus having control means for controlling each sirocco fan may be used.

(Modification 4 of the second embodiment)
A modification 4 of the second embodiment will be described with reference to FIGS. 10, 11, and 17.
As shown in FIGS. 10, 11, and 17, the modified example 4 is an operation panel 90 instead of the paper feeding unit 1 </ b> B of the air paper feeding device 1 and the stencil printing apparatus main body 153 having the air feeding device 1 of the second embodiment. The main point is to use a stencil printing apparatus main body 155 having a paper type setting means as a paper type recognizing means, a temperature sensor 67 such as a thermistor disposed in the apparatus main body, and a control means 77. Is different. The modification 4 has the same configuration as that of the second embodiment except for the above differences, and it is a matter of course that the modified example 4 has the same sheet feeding unit 1B of the air feeding device 1 as that of the second embodiment. is there.

  The control unit 77 selects any one paper type from the thin paper setting key 131, the plain paper setting key 132, the coated paper setting key 133, and the thick paper setting key 134 selected and set by the paper type setting unit as the sheet type recognition unit. In accordance with the temperature in the apparatus main body 50 detected by the temperature sensor 67, the sirocco fans 41a and 41b have a function of controlling the rotational speed and the air volume to be changed.

In the modified example 4, in addition to the control specific to the modified example 3 by the control means 76, when the coated paper (coated paper) is thicker under high temperature and high humidity conditions, it becomes difficult to separate the sheets one by one. Therefore, the number of rotations of both sirocco fans 41a and 41b is maximized (rated voltage 24V) by a command from the control means 76.
According to the modified example 4, the same effect as in the second embodiment can be obtained, and when using thick paper and coated paper (coated paper), the thick paper mode is set by pressing the thick paper setting key 134. At the same time, the coated paper (coated paper) mode is set by pressing the coated paper setting key 133, and the temperature from the temperature sensor 67 is higher than the temperature stored in advance in a ROM or the like (not shown) (for example, 27 ° C.). The control means 77 automatically maximizes the rotation speed of both the sirocco fans 41a and 41b (rated voltage 24V), so that the maximum side air speed (wind speed) can be obtained. Even when thick paper of coated paper (coated paper) is used, the paper S can be surely separated one by one.
In addition, when it is desired to detect a high temperature and high humidity state more accurately, it is preferable to employ a known temperature / humidity sensor in which a temperature sensor and a humidity sensor as temperature / humidity detection means are integrated.

  In the modification 4, the control unit 77, the sheet type recognition unit, and the temperature sensor 67 as the temperature detection unit are described on the stencil printing apparatus main body 154 side. However, the present invention is not limited to this. The temperature sensor 67 as the type recognizing unit and the temperature detecting unit may be arranged on the side of the sheet feeding unit 1B in the air sheet feeding device 1 as the sheet feeding device. In a sheet feeding apparatus according to claim 6, a configuration that expresses this conceptually, that is, a sheet type recognition unit that recognizes a sheet type, a temperature detection unit that detects a temperature of the sheet feeding apparatus, A sheet feeding device having control means for controlling each sirocco fan in accordance with the sheet type recognized by the sheet type recognition means and the temperature of the sheet feeding device detected by the temperature detection means. May be.

(Modification 5 of the second embodiment)
A modification 5 of the second embodiment will be described with reference to FIGS. 10, 11, and 18.
In the fifth modification, instead of the paper feeding unit 1B of the air paper feeding device 1 of the second embodiment and the stencil printing machine main body 153 having the air feeding device 1, as shown in FIGS. The main difference is that a stencil printing apparatus main body 156 having a double feed sensor 79 as a double feed recognition means / multiple feed detection means for recognizing double feed and a control means 78 is used. The modified example 5 has the same configuration as that of the second embodiment except for the above differences, and it is needless to say that the modified example 5 includes the same sheet feeding unit 1B of the air sheet feeding device 1 as that of the second embodiment. is there.

The control unit 78 has a function of controlling the sirocco fans 41a and 41b to change the rotation speed and the air volume by the double feed of the paper S detected by the double feed sensor 79. The double feed sensor 79 of the present embodiment is disposed on a paper transport path between a paper exit transported from the paper feed unit 1B and the pair of registration rollers 113 and 113b.
The double feed sensor 79 is constituted by, for example, a photodiode disclosed in Japanese Patent Laid-Open No. 7-121079 in FIG. 1 and paragraph “0012”, and detects a double feed from a change in the transmittance of the paper. An example using the feed sensor (7) is given. Further, a double feed sensor (10) using an ultrasonic sensor disclosed in FIG. 2 and paragraph “0023” of Japanese Patent Laid-Open No. 2000-159393, or a known sensor using an optical sensor may be used.
The double feed recognition means includes a double feed setting means for setting the occurrence of double feed in addition to the double feed detection means for automatically detecting double feed.

  When double feeding of the sheet S is detected by the double feeding sensor 79, the voltage of the currently operating sirocco fans 41a and 41b is increased by about 2V in accordance with a command from the control means 78, and thereby the sirocco fans 41a and 41b are controlled. By increasing the rotation speed, the speed (wind speed) of the side air is automatically increased, so that the sheets S can be reliably separated one by one in the sheet feeding / separating operation after the jam processing. It becomes like this.

This cannot be dealt with when each sirocco fan 41a, 41b is operated at a maximum voltage of 24V. However, when a double feed occurs at a voltage other than 24V, the double feed is detected by a command from the control means 78. Since the warning is displayed on the LCD screen of 98 and the warning is notified by the buzzer 97, the user understands that the double feeding is performed by the warning display and the warning sound, and is appropriately disposed on the touch panel 98 of the operation panel 90 or the like. By pressing a multi-feed mode key (not shown) or a multi-feed mode button as a multi-feed setting unit, it is possible to cope with the same as described above.
Not limited to the above-described example, when double feeding continues two or more times, the voltage of the currently operating sirocco fans 41a and 41b is increased, thereby increasing the rotational speed of the sirocco fans 41a and 41b. The side air speed (wind speed) can be automatically increased.

  In the modified example 5, the control unit 78 is described as being disposed on the stencil printing apparatus main body 155 side. However, the present invention is not limited to this, and the control unit 78 and the double feed sensor 79 as the double feed recognition unit / double feed detection unit are described. Can be arranged on the side of the paper feeding unit 1B in the air paper feeding device 1 as a sheet feeding device. In the sheet feeding apparatus according to claim 6, the multi-feed recognition unit for recognizing the multi-feed of the sheet and the multi-feed of the sheet recognized by the multi-feed recognition unit. The sheet feeding device may include a control unit that controls the sirocco fan for each of the air blowing drive sources.

  The present invention is not limited to a printing apparatus including a stencil printing machine (stencil printing apparatus), an offset printing machine, and the like, but an electrophotographic copying machine, a printer, an ink jet recording apparatus, or a complex machine including at least a plurality of these. Of course, the present invention can also be applied to other image forming apparatuses. When the present invention is applied to an image forming apparatus, “printing apparatus” may be read as “image forming apparatus”, and “print image forming means” may be read as “image forming means”.

The present invention includes two or more inventions. That is, the invention corresponding to the second embodiment and the modifications 3 to 5 can be configured independently of the invention corresponding to the first embodiment and the modifications 1 and 2. If these are expressed conceptually, they are the following first to seventh technical configurations.
That is, the first technical configuration includes an air separating unit that separates the sheets one by one by blowing air onto both side end surfaces of the stacked sheet bundle, an air suction unit that sucks the separated uppermost sheet, In the sheet feeding device having a sheet feeding unit that feeds the sheet sucked and held by the air suction unit, the air separating unit includes a side air discharge port that blows air to each side end surface of the sheet bundle, A plurality of sirocco having an air suction port for sucking air and an air discharge port for discharging air; and an air blowing drive source connected to and connected to the side air discharge port. The air suction port of the sirocco fan on the downstream side adjacent to the sirocco fan on the upstream side is connected to and connected to the air discharge port of the sirocco fan on the upstream side. Characterized in that the placed.

  A second technical configuration is characterized in that, in the sheet feeding device described in the first technical configuration, each of the sirocco fans has an equivalent static pressure specification.

  According to a third technical configuration, in the sheet feeding device described in the first or second technical configuration, each sirocco fan can change a static pressure and an air volume by changing a rotation speed. It is characterized by comprising.

  According to a fourth technical configuration, there is provided an image forming apparatus that feeds a sheet to form an image on the sheet, the sheet feeding device according to any one of the first to third technical configurations, and the sheet feeding. And image forming means for forming an image on the sheet fed by the feeding device.

  According to a fifth technical configuration, in the image forming apparatus described in the fourth technical configuration, a sheet type recognition unit that recognizes a sheet type, and each sirocco according to the type of sheet recognized by the sheet type recognition unit. And a first control means for controlling the fan.

  According to a sixth technical configuration, in the image forming apparatus described in the fourth or fifth technical configuration, a sheet type recognition unit that recognizes a sheet type, a temperature detection unit that detects a temperature of the image forming apparatus, and the sheet And a second control unit that controls each of the sirocco fans in accordance with the type of the sheet recognized by the type recognition unit and the temperature of the image forming apparatus detected by the temperature detection unit.

  According to a seventh technical configuration, in the image forming apparatus described in any one of the fourth to sixth technical configurations, a double feed recognition unit that recognizes a double feed of a sheet and a sheet recognized by the double feed recognition unit. And third control means for controlling each of the sirocco fans by double feeding.

As described above, the present invention has been described with respect to specific embodiments, modifications, and the like. However, the technical scope disclosed by the present invention is limited to those exemplified in the above-described embodiments, modifications, or examples. However, it should be understood that various embodiments, modifications, or examples may be configured within the scope of the present invention in accordance with the necessity and application thereof. It will be clear to the trader.
For example, a control configuration in which the above-described modifications 1 to 5 are appropriately combined may be used. From the content of the invention disclosed in the present application, a person skilled in the art can control all of the modifications 1 to 5 etc. It can be easily understood and implemented.

It is a typical top view which shows the principal part (communication and connection state of two sirocco fans) of the suction unit in the paper feed unit of the air paper feeder of the first embodiment of the present invention. It is a bottom view of FIG. (A) is a bottom view showing a product example of a sirocco fan, (b) is a right side view of the fan, and (c) is a plan view of the fan. It is a block diagram which shows the control structure of the modification 1 of 1st Embodiment. It is a block diagram which shows the control structure of the modification 2 of 1st Embodiment. It is a schematic partial sectional front view which shows the principal part of the conventional air feeder. FIG. 7 is a schematic plan view of FIG. 6. FIG. 7 is a schematic partial cross-sectional front view showing a main part of a conventional air sheet feeding device different from FIG. 6. 1 is a schematic front view showing an overall configuration of a stencil printing apparatus to which the present invention is applied. It is a front view which shows the whole structure of the stencil printing apparatus main body of FIG. It is a top view of the operation panel used for modification 1 thru | or 5 grade | etc.,. It is a schematic partial sectional front view which shows the principal part of the air paper feeder of the 2nd Embodiment of this invention. It is a typical front view which shows the principal part (communication and connection state of two sirocco fans) in the side discharge unit of FIG. FIG. 13 is a schematic partial cross-sectional front view of FIG. 12. It is a schematic side view of the side discharge unit of FIG. It is a block diagram which shows the control structure of the modification 3 of 2nd Embodiment. It is a block diagram which shows the control structure of the modification 4 of 2nd Embodiment. It is a block diagram which shows the control structure of the modification 5 of 2nd Embodiment.

Explanation of symbols

1 Air feeding device (sheet feeding device)
1A, 1B Paper feed unit 2 Paper bundle (sheet bundle)
3 Paper feed tray (sheet stacking stand, paper feed stand)
10A Suction unit 11 Suction belt (composed of air suction means / sheet feeding means)
12 Suction chamber (composes air suction means)
13 Suction relay pipe (composed of air suction means)
14a Drive roller (constitutes sheet feeding means)
14b Follower roller (constitutes sheet feeding means)
15a, 15b Sirocco fan (composed of air suction drive source and air suction means)
15a2 Upstream sirocco fan air discharge port 15b1 Downstream sirocco fan air suction port 15c Multi-blade fan 17 Suction drive source chamber (configures air suction means)
23 Front air discharge fan (Consists of front air discharge source and air separation means)
40A Side discharge unit (constitutes air separation means)
41a, 41b Sirocco fan for air blowing drive source (composed of air blowing drive source and air separating means)
41a1 Air blowing drive source air suction port of the sirocco fan for air blowing drive source on the downstream side 41b2 Air blowing drive source air discharge port of the sirocco fan for upstream air blowing drive source 42a to 42d Side discharge nozzles (side air discharge) Exit)
45 Fan connection duct (composed of air suction means)
46 Fan connection duct (composed of air separation means)
50 Device body 65, 66, 76, 77, 78 Control means 67 Temperature sensor (temperature detection means)
79 Double feed sensor (Double feed detection means)
121 Print drum (constitutes print image forming means)
123 Press roller (constitutes printing image forming means)
131 Thin paper setting key (sheet type setting means / sheet type recognition means)
133 Coated paper setting key (sheet type setting means / sheet type recognition means)
134 Thick paper setting key (sheet type setting means / sheet type recognition means)
150 to 156 Stencil printing machine body (printing machine)
S paper (sheet, printing medium)
X Paper transport direction (sheet transport direction, sheet feed direction)
Y Paper width direction (sheet width direction)
Z height direction

Claims (12)

After separating the sheets one by one from the stacked sheet bundle, an air suction means having an air suction drive source for sucking the separated uppermost sheet, and a sheet sucked and held by the air suction means are supplied. In a sheet feeding apparatus having a sheet feeding means for feeding,
The air suction drive source comprises a plurality of sirocco fans having an air suction port for sucking air and an air discharge port for discharging air,
A sheet feeding device characterized in that the air suction port of the downstream sirocco fan adjacent to the upstream sirocco fan is connected to and connected to the air discharge port of the upstream sirocco fan. apparatus. The sheet feeding apparatus according to claim 1,
Each of the sirocco fans has the same static pressure specification. In the sheet feeding apparatus according to claim 1 or 2,
Each of the sirocco fans comprises a DC fan that can change a static pressure and an air volume by changing a rotation speed. In the sheet feeding apparatus according to any one of claims 1 to 3,
Air separation means for separating the sheets one by one by blowing air onto both end faces of the stacked sheet bundle;
The air separating means has a side air discharge port that blows air to each side end surface of the sheet bundle, and an air blowing drive source that is connected to and connected to the side air discharge port.
The air blowing drive source comprises a plurality of air blowing drive source sirocco fans having an air blowing drive source air suction port for sucking air and an air blowing drive source air discharge port for discharging air,
The sirocco fan for the air blowing drive source on the downstream side adjacent to the sirocco fan for the air blowing drive source on the upstream side is connected to the air discharge port for the air blowing drive source of the sirocco fan for the air blowing drive source on the upstream side. A sheet feeding apparatus, wherein the air suction port for the air blowing drive source is arranged in communication and connected. The sheet feeding apparatus according to claim 4, wherein
Each of the air blowing drive source sirocco fans is equivalent in static pressure specification. In the sheet feeding apparatus according to claim 4 or 5,
Each of the air blowing drive source sirocco fans includes a DC fan capable of changing a static pressure and an air volume by changing a rotation speed. In a printing apparatus that feeds a sheet and forms a printed image on the sheet,
A sheet feeding device according to any one of claims 1 to 6,
Print image forming means for forming a print image on the sheet fed by the sheet feeding device;
A printing apparatus comprising: In a printing apparatus that feeds a sheet and forms a printed image on the sheet,
A sheet feeding device according to claim 3;
Print image forming means for forming a print image on the sheet fed by the sheet feeding device;
Sheet type recognition means for recognizing the type of sheet;
Control means for controlling each sirocco fan according to the type of sheet recognized by the sheet type recognition means;
A printing apparatus comprising: In a printing apparatus that feeds a sheet and forms a printed image on the sheet,
A sheet feeding device according to claim 3;
Print image forming means for forming a print image on the sheet fed by the sheet feeding device;
Sheet type recognition means for recognizing the type of sheet;
Temperature detecting means for detecting the temperature of the printing apparatus;
Control means for controlling each sirocco fan according to the sheet type recognized by the sheet type recognition means and the temperature of the printing apparatus detected by the temperature detection means;
A printing apparatus comprising: In a printing apparatus that feeds a sheet and forms a printed image on the sheet,
A sheet feeding device according to claim 6;
Print image forming means for forming a print image on the sheet fed by the sheet feeding device;
Sheet type recognition means for recognizing the type of sheet;
Control means for controlling each air blowing drive source sirocco fan according to the type of sheet recognized by the sheet type recognition means;
A printing apparatus comprising: In a printing apparatus that feeds a sheet and forms a printed image on the sheet,
A sheet feeding device according to claim 6;
Print image forming means for forming a print image on the sheet fed by the sheet feeding device;
Sheet type recognition means for recognizing the type of sheet;
Temperature detecting means for detecting the temperature of the printing apparatus;
Control means for controlling the air blowing drive source sirocco fans according to the sheet type recognized by the sheet type recognition means and the temperature of the printing apparatus detected by the temperature detection means;
A printing apparatus comprising: In a printing apparatus that feeds a sheet and forms a printed image on the sheet,
A sheet feeding device according to claim 6;
Print image forming means for forming a print image on the sheet fed by the sheet feeding device;
A double feed recognition means for recognizing the double feed of the sheet;
Control means for controlling each sirocco fan for each air blowing drive source by double feeding of the sheets recognized by the double feeding recognition means;
A printing apparatus comprising:

Images