JP2005313486A - Powder spreading device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the adhesion efficiency of powder in terms of a powder spreading device for being used for spreading anti-offset powder, mixed with air, on a sheet in a sheet ejecting part of a sheet-fed press. <P>SOLUTION: This powder spreading device is provided in a sheet ejector 70 of the sheet-fed press for sequentially piling the printed sheets 2 on a piling table 12 . The powder spreading device is equipped with a spreading means 71 for spreading the anti-offset powder, mixed with the air, between uppermost one of sheets 2, piled on the piling table 12, and the sheet 2 superposed under it. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a powder spraying device used for spraying powder for preventing show-through mixed with air on a sheet of paper in a paper discharge unit of a sheet-fed printing press.

4 to 6 are views for explaining a powder spraying device provided in a paper discharge unit of a conventional sheet-fed printing press. FIG. 4 is a side view showing the paper discharge unit, and FIG. FIG. 6 is a front view of the powder injection device viewed from the paper transport direction.
As shown in FIG. 4, the sheet discharge unit 3 of the sheet-fed printing machine is generally a sheet that has been printed by a printing apparatus (not shown) in the previous process and conveyed while being held by the nail 1 a of the impression cylinder 1. A leaf paper (hereinafter simply referred to as paper) 2 is received by a chain gripper 7 provided on an endless chain (hereinafter simply referred to as chain) 6 that is wound around a paper discharge cylinder 4 and a driven shaft 5 and travels along a predetermined path. They are conveyed while being held by the chain gripper 7 and stacked on the pile base 12. In FIG. 4, reference numeral 15 denotes a guide for stabilizing the traveling posture of the paper 2.

As shown in FIG. 5, the paper discharge cylinder 4 is a paper discharge cylinder in which both shaft end portions 4b and 4b are pivotally supported by side frames 8 and 8 installed at both ends in the width direction of the printing press (machine width direction). A shaft 4a is provided. Further, sprockets 9 and 9 are fixed to both sides of the discharge cylinder shaft 4a close to the side frames 8 and 8, and the chains 6 and 6 are engaged with the sprockets 9 and 9, respectively.
Further, a shaft 10 connecting the chains 6 and 6 is fixed between the chains 6 and 6. A plurality of shafts 10 are provided between the chains 6 and 6 at a distance substantially equal to the distance between the claws 1 a and 1 a on the circumference of the impression cylinder 1. A plurality of chain grippers 7 are fixed side by side in the axial direction (that is, the paper width direction) of each shaft 10, gripping a plurality of locations in the width direction of the front end portion of the paper 2, and transporting the paper 2 above the pile table 12. It is supposed to be.

  Further, as shown in FIG. 4, a vacuum suction wheel 13 that generates a suction force in accordance with the timing at which the rear end of the paper 2 passes is provided on the upstream side (inlet part) in the paper transport direction above the pile table 12. In addition, a paper pad (stopper) 14 for restricting the movement of the paper 2 is provided on the upstream side in the paper transport direction above the pile table 12. Furthermore, a fan 16 provided above the pile table 12 and blows air onto the upper surface of the paper 2 when the paper 2 is released from the gripped state by the chain gripper 7, and a paper aligning plate for aligning the position of the paper 2 in the paper width direction 17 and 17 (in FIG. 4, only the rear-side paper alignment plate is shown).

  As a result, the paper 2 conveyed to the upper side of the pile base 12 by the chain gripper 7 is released from the chain gripper 7 and at the rear end of the paper 2 by the vacuum suction wheel 13 provided at the inlet portion above the pile base 12. Are sucked and hit the paper pad 14 in a decelerated state, and are piled up on the pile table 12. At this time, with the paper width direction position determined by the paper aligning plates 17, 17, air is blown onto the upper surface of the paper 2 by the fan 16, and the paper 2 is stably lowered.

  By the way, normally, the paper 2 is conveyed by the chain gripper 7 with the printing surface facing up, and is sequentially stacked on the pile base 12 in this state. At this time, the back surface of the paper 2 (the surface on the back side of the printing surface). However, there may be a case where the show-through occurs due to contact with the upper surface of the paper 2 immediately below, that is, the printing surface. For this reason, a fine powdery anti-sticking agent (hereinafter referred to as powder) is formed on the printing surface of the paper 2 in the transport path from when the paper 2 is printed by the printing apparatus to when it is stacked on the pile table 12. ) Is mixed with a large amount of air and sprayed.

  The conventional powder injection device 100 is provided on the downstream side of the paper discharge cylinder 4 in the paper transport direction and at a location facing the printing surface of the paper 2. Specifically, as shown in FIG. 6, the powder injection device 100 includes a tube 101 spanned between the side frames 8 and 8, and a tube 101 at a location facing the printing surface of the paper 2 on the circumferential surface of the tube 101. A plurality of nozzles 102 arranged side by side in the axial direction, a hose 103 connected to the pipe 101, and a supply device 104 that supplies powder mixed with air to the hose 103. With such a configuration, the powder supplied from the supply device 104 is jetted onto the printing surface of the paper 2 through the hose 103, the pipe 101 and the nozzle 102.

For example, Patent Document 1 discloses a technique in which a powder injection device is provided in the middle of the ascending conveyance path on the downstream side in the paper conveyance direction of the paper discharge cylinder 4, similarly to the technique described above.
Japanese Patent No. 3184529

However, in the above-described conventional powder device 100, since the powder collides with the printing surface of the paper 2 together with a large amount of air, air turbulence easily occurs, and the sprayed powder can be efficiently attached to the printing surface of the paper 2. There is a problem that it cannot be done.
If the nozzle 102 is arranged at a position close to the paper 2, it is considered that the powder can be efficiently attached to the printing surface of the paper 2 even if the ejection speed is low, but actually, as shown in FIG. The nozzle 102 needs to be disposed at a position separated from the paper 2 by a predetermined distance (the height of the chain gripper 7) so that the nozzle 102 does not hinder the travel of the chain gripper 7. For this reason, it is necessary to spray the powder at a higher speed, and the adhesion efficiency of the powder is reduced.

In addition, although the nozzle 102 is fixed, the paper 2 is conveyed at a high speed by the chain gripper 7, so that the relative speed between the nozzle 102 and the paper 2 is large, as compared with the case where powder is sprayed on a stationary paper. Adhesion efficiency is significantly reduced.
Thus, when the adhesion efficiency of powder falls, the quantity of the powder which will be scattered without adhering to the paper 2 will also increase. Since the powder that has not adhered to the paper rides on the air flow and spreads and accumulates not only in the vicinity of the powder jetting apparatus but also in and out of the printing machine, there is a risk of contaminating the periphery of the printing machine. In addition to consuming a larger amount of powder than necessary, the accumulated powder may fall on the printing surface of the paper 2 and damage the product.
The problem as described above can occur in the technique of Patent Document 1 as well.

  The present invention was devised in view of such problems, and an object of the present invention is to provide a powder spraying device capable of improving the adhesion efficiency of powder.

For this reason, the powder spraying device according to the first aspect of the present invention is a powder spraying device provided in a paper discharge device of a sheet-fed printing machine in which printed sheets are sequentially stacked on a pile table. A spraying means for spraying a powder for preventing show-through mixed with air between the uppermost sheet stacked on the pile table and the next stacked sheet; It is characterized by having it.
The powder spraying device of the present invention according to claim 2 is the device according to claim 1, wherein the spraying means is between the uppermost sheet and the next stacked sheet. A side plate provided so as to surround the four sides of the space to be formed, a hole formed in the side plate, and a nozzle for injecting powder into the space through the hole. It is characterized by.

A powder spraying device according to a third aspect of the present invention is the device according to the second aspect, wherein a plurality of the holes and the nozzles are provided.
A powder spraying device according to a fourth aspect of the present invention is the device according to any one of the first to third aspects, wherein each sheet is provided below the spraying means and stacked on the pile table. The present invention is characterized in that there is provided suction collecting means for sucking and collecting air between the paper and excess powder.

  According to a fifth aspect of the present invention, in the powder spraying device according to the fourth aspect of the present invention, the suction recovery means is provided so as to surround the four sides of the sheets stacked on the pile table. A suction box having a suction hole at a portion facing the sheet and a suction device for sucking the inside of the suction box are provided.

According to the powder spraying device of the present invention according to claim 1, after the next sheet is stacked on the uppermost sheet, the powder adheres to the sheet by its own weight, The adhesion efficiency can be further improved. Thereby, since powder scattering can be reduced, it can suppress that powder accumulates around a printing machine.
According to the powder spraying device of the present invention as set forth in claim 2, the powder is sprayed after the space between the uppermost sheet and the next stacked sheets is made substantially closed by the side plate. Therefore, it is possible to further reduce the powder scattering to the outside.

According to the powder spraying device of the present invention, the space between the uppermost sheet and the next stacked sheet can be filled with the powder in a short time by the side plate. .
According to the powder spraying device of the present invention as set forth in claim 4, it is possible to reliably recover surplus powder.
According to the powder spraying apparatus of the present invention described in claim 5, it is possible to collect the powder while preventing the excessive powder from scattering.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1-3 is a figure for demonstrating the powder dispersal apparatus which concerns on one Embodiment of this invention, Comprising: FIG. 1 is the side view (AA arrow sectional drawing of FIG. 2), FIG. A top view and FIG. 3 are perspective views thereof. 1 to 3, the same parts as those in the conventional example described above are denoted by the same reference numerals. 2 and 3, the paper pad 14 is omitted.

  As shown in FIG. 1, the powder spraying apparatus according to the present embodiment is provided in a paper discharge device 70 in a paper discharge unit 3 of a sheet-fed printing press and is stacked on a pile table (loading table) 12. The sheet 2 (hereinafter simply referred to as “paper”) 2 and the next stacked paper 2 are configured to spray a show-through preventing powder (hereinafter referred to as “powder”) mixed with air. . That is, the configuration is completely different from a conventional powder injection apparatus that injects powder onto paper being conveyed.

  The paper discharge unit 3 is provided with a vacuum suction wheel 13 that generates a suction force at the timing when the rear end of the paper 2 passes on the upstream side (inlet part) in the paper conveyance direction above the pile table 12. In addition, a paper pad (stopper) 14 for restricting the movement of the paper 2 is provided on the upstream side in the paper transport direction above the pile table 12. Furthermore, a fan 16 that is provided above the pile base 12 and blows air onto the upper surface of the paper 2 when the paper 2 is released from the gripped state by the chain gripper 7, and a paper aligning plate for aligning the paper 2 in the paper width direction 20 and 21 (refer to FIG. 2 and FIG. 3 for the paper aligning plate 21). The vacuum suction wheel 13, the paper pad 14, the fan 16, and the paper aligning plates 20 and 21 are supported by a support member (not shown).

The pile table 12 is moved up and down by a control device (not shown) so that the height position of the uppermost paper 2 stacked on the pile table 12 is always a predetermined position. That is, as the number of sheets 2 stacked on the pile table 12 increases, the pile table 12 gradually descends.
As shown in FIGS. 1 to 3, the present powder spraying device prevents the show-through mixed with air between the uppermost paper 2 stacked on the pile table 12 and the next paper 2 stacked. Spraying means 71 for spraying the powder for use. The spreading means 71 is composed of the uppermost paper 2 among the papers 2 already stacked on the pile table 12 (the whole sheets stacked in this way are also called piles), and the uppermost paper. 2, flat side plates 30, 31, 32, and 33 are provided so as to surround the four sides of the space formed between the next paper 2 stacked on the 2. The spraying means 71 sprays powder through the holes 30a, 31a, 32a, 33a and the holes 30a, 31a, 32a, 33a formed in the side plates 30, 31, 32, 33, respectively. Nozzles 60, 61, 62, 63.

Here, the side plate 30 is the right side of the paper 2 in the paper conveyance direction (in FIG. 1, rear side), the side plate 31 is the left side of the paper 2 in the paper conveyance direction (front side in FIG. 1), and the side plate 32 is the paper conveyance direction of the paper 2 The downstream side (left side in FIG. 1) and the side plate 33 are arranged on the upstream side (right side in FIG. 1) of the paper 2 in the paper conveyance direction.
Further, the side plate 30 is disposed outside the paper aligning plate 20 so as to partially overlap the paper aligning plate 20, and the paper aligning plate 20 is provided with a hole 20 a at a position corresponding to the hole 30 a of the side plate 30. Has been. Similarly, the side plate 31 is disposed outside the paper aligning plate 21 so as to partially overlap the paper aligning plate 21, and the paper aligning plate 21 has a hole 21 a at a position corresponding to the hole 31 a of the side plate 31. Is drilled. Further, the holes 30a, 31a, 32a, 33a, 20a, and 21a are arranged above the position of the uppermost paper 2.

In this embodiment, the paper alignment plates 20 and 21 are provided. However, the side plates 30 and 31 have the function of the paper alignment plates 20 and 21 (that is, the function of aligning the paper width direction position of the paper 2). Of course. In this case, it is not necessary to provide the paper alignment plates 20 and 21 in particular.
The powder sprayed from each nozzle 60, 61, 62, 63 is supplied from a mixing device (powder supply source) 66 through a hose 65. The mixing device 66 mixes powder for preventing show-through with air, and at the timing when the paper 2 is stacked on the pile table 12 (that is, while the paper 2 is descending), the nozzles 60, 61, 62. , 63 and the powder is ejected from the nozzles 60, 61, 62, 63.

  Further, below the spraying means 71, there is provided a suction collecting means 72 for sucking and collecting excess powder and air between the sheets 2 stacked on the pile table 12. Specifically, cube-shaped suction boxes 40, 41, 42, and 43 are provided at positions close to the lower portions of the side plates 30, 31, 32, and 33, respectively. The suction boxes 40, 41, 42, 43 are provided so as to surround the four sides of the paper 2 stacked on the pile table 12.

  Further, suction holes 50, 51, 52, 53 are formed on the surfaces of the suction boxes 40, 41, 42, 43 facing the paper 2. 1 to 3, the suction holes 51 are not shown, but are formed on the surface of the suction box 41 facing the paper 2.

  Here, the surface of the suction boxes 40, 41, 42, 43 facing the paper 2 (that is, the surface facing the pile side surface) is formed of a wire mesh, and the mesh of the wire mesh is the suction holes 50, 51, 52 and 53 function. Further, the suction boxes 40, 41, 42, 43 are arranged such that the surface facing the paper 2 (that is, the surface of the wire net) is continuous with the surface facing the paper 2 of the side plates 30, 31, 32, 33 without any step. ing.

Note that the size of the suction holes 50, 51, 52, and 53 (that is, the size of the wire mesh) may be set to a size that allows at least the powder to pass through. Further, the wire mesh can be removed, and can be easily replaced when clogging occurs.
Suction tubes 40 a, 41 a, 42 a, and 43 a protrude from the suction boxes 40, 41, 42, and 43, respectively. Further, a hose 45 is connected to the suction pipes 40 a, 41 a, 42 a and 43 a, and the hose 45 is connected to a suction device 46. The suction device 46 sucks the inside of the suction boxes 40, 41, 42, and 43 through the hose 45 and the suction tubes 40a, 41a, 42a, and 43a.

  The suction timing by the suction device 46 can be set as appropriate by a control device (not shown). For example, the suction timing may be intermittently sucked every time the pile base 12 is lowered little by little. The spraying means 71 and the suction collecting means 72 are supported by a support member (not shown).

  Since the powder spraying apparatus according to an embodiment of the present invention is configured as described above, first, when the paper 2 is conveyed to the upper side of the pile base 12 by the chain gripper 7 with the printing surface up, the chain gripper 7, the rear end portion of the paper 2 is sucked by the vacuum suction wheel 13 provided at the inlet portion above the pile table 12, and the front end portion hits the paper pad 14 in a decelerated state. Then, with the paper width direction position determined by the paper aligning plates 20 and 21 (and also by the side plates 30, 31, 32, and 33), air is blown onto the upper surface of the paper 2 by the fan 16, so that the paper 2 is stable. To descend.

  Then, powder mixed with air is sprayed from the nozzles 60, 61, 62, and 63 between the lowering paper (that is, the next paper to be stacked) 2 and the uppermost paper 2. At this time, the space formed by the paper 2 to be stacked next, the uppermost paper 2, the side plates 30, 31, 32, 33 and the paper alignment plates 20, 21 is an incomplete but closed space. Thus, the powder sprayed from the nozzles 60, 61, 62, and 63 is filled (that is, dispersed) in this space.

Thereafter, the paper 2 is further lowered by its own weight action, and further by the action of the descending air flow by the fan 16, and is stacked on the uppermost paper 2. In this way, the papers 2 are successively stacked on the 12 piles.
As the paper 2 is stacked, the 12 piles are gradually lowered and the gap between the papers 2 is narrowed, and the powder sandwiched between the papers 2 adheres to the paper 2 by its own weight. Thereby, the show-through of the paper 2 is prevented. Further, the air and surplus powder existing between the papers 2 slowly flow out in all directions, but the air and surplus powder are sucked into the suction boxes 40, 41, 42, and 43 and collected.

Thus, after the paper 2 to be stacked next is stacked on the uppermost paper 2, the powder adheres securely to the printing surface of the paper 2 by its own weight, so that the adhesion efficiency is further improved. Can do. Thereby, since powder scattering can be reduced, it can suppress that powder accumulates around a printing machine.
Further, the powder is sprayed to the outside because the space between the next stacked paper 2 and the uppermost paper 2 is made a substantially closed space by the side plates 30, 31, 32, 33. This can be further reduced. Furthermore, since the powder is sprayed by the plurality of nozzles 60, 61, 62, 63, it is possible to fill the space in a short time.

  Further, since the suction boxes 40, 41, 42, 43 are provided so as to surround the four sides of the paper 2 stacked on the pile table 12, the suction boxes 40, 41, 42, 43 are reliably collected while preventing the scattering of excess powder. be able to.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, only one nozzle may be provided. In the present embodiment, the surface of the suction boxes 40, 41, 42, 43 facing the paper 2 is formed of a metal mesh, but instead of the metal mesh, suction holes are directly formed in the suction boxes 40, 41, 42, 43. You may set up. Further, in the present embodiment, suction boxes 40, 41, 42, 43 are provided on the four sides of the paper 2 stacked on the pile table 12, and the suction boxes 40, 41, 42, 43 are separately sucked. However, the suction boxes 40, 41, 42, and 43 may be connected and sucked together.

It is a side view (AA arrow sectional view of Drawing 2) showing typically a powder spraying device concerning one embodiment of the present invention. It is a top view which shows typically the powder spraying apparatus which concerns on one Embodiment of this invention. It is a perspective view showing typically a powder spraying device concerning one embodiment of the present invention. It is a side view which shows typically the paper discharge part of the conventional sheet-fed printing press. It is a figure which shows typically the paper discharge cylinder provided in the paper discharge part of the conventional sheet-fed printing machine, Comprising: It is the DD arrow line view of FIG. It is a figure which shows typically the powder injection apparatus provided in the paper discharge part of the conventional sheet-fed printing machine, Comprising: It is the front view seen from the paper conveyance direction.

Explanation of symbols

1 Impression cylinder 1a Impression nail 2 Paper (sheet)
DESCRIPTION OF SYMBOLS 3 Paper discharge part 4 Paper discharge cylinder 4a Paper discharge cylinder shaft 4b Shaft end part 5 Drive shaft 6 Chain 7 Chain gripper 8 Side frame 9 Sprocket 10 Shaft 12 Pile stand 13 Vacuum suction wheel 14 Paper application 15 Guide 20, 21 Paper alignment board 30, 31, 32, 33 Side plate 30a, 31a, 32a, 33a Side plate hole 40, 41, 42, 43 Suction box 40a, 41a, 42a, 43a Suction tube 45 Hose 46 Suction device 50, 51, 52, 53 Suction hole 60, 61, 62, 63 Nozzle 65 Hose 66 Mixing device (powder supply source)
70 Paper Discharge Device 71 Spraying Means 72 Suction Collection Mean

Claims (5)

A powder spraying device provided in a paper discharge device of a sheet-fed printing machine that sequentially stacks printed sheets on a pile table,
A spraying means for spraying a powder for preventing show-through mixed with air is provided between the uppermost sheet stacked on the pile table and the next stacked sheet. Characteristic powder spraying device. The spraying means
A side plate provided so as to surround the four sides of the space formed between the uppermost sheet and the next stacked sheet;
A hole drilled in the side plate;
The powder spraying device according to claim 1, further comprising a nozzle that sprays powder into the space through the hole. The powder spraying apparatus according to claim 2, wherein a plurality of the holes and the nozzles are provided. The suction and recovery means, which is provided below the spraying means and sucks and collects air and excess powder between the sheets stacked on the pile table, is provided. The powder spraying apparatus of any one of 1-3. The suction recovery means comprises:
A suction box provided so as to surround the four sides of the sheets stacked on the pile table, and having a suction hole in a portion facing the sheets;
The powder spraying device according to claim 4, comprising a suction device that sucks the inside of the suction box.

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