JP2924077B2 - Powder sprayer for paper ejection section of printing press - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a discharge section of a sheet-fed printing press, in which an appropriate amount of powder is sprayed on a printing paper surface to be printed and discharged, and the back of the printing ink is printed. The present invention relates to a powder spray device for discharging and stacking printing paper while preventing transfer.

(Prior Art) Conventionally, the printing ink adhering surface of printing paper which is printed by a sheet-fed printing press and sequentially discharged is provided with a fine powder of a slippery material such as silica on each of the discharged printing paper. Is sprayed by a powder spray device so that the printing ink does not set off on the back surface of the printing paper to be discharged next. The powder spraying device sprays a predetermined amount of powder on a sheet of printing paper. However, if the amount of powder spraying is too small or too large, it is inconvenient for printing paper. Conventionally, it is necessary to spray powder. Conventionally, the dial of an opening / closing valve for adjusting the spraying amount of the spraying device is manually rotated to adjust the amount of printing ink. Subtle adjustments are required depending on the size of the ink image area), and considerable time and skill are required for the initial setting of the powder spray amount, such as determining the spray amount while monitoring the printed matter that is printed and discharged. I needed it.

(Purpose of the Invention) The present invention is intended to automatically perform the initial setting of the powder spray amount and correct the powder spray amount while actually measuring the amount of powder used after the start of printing. It is intended to be.

(Constitution of the Invention) The present invention relates to a powder spraying device of a paper ejection part of a printing machine for sequentially spraying powder such as silica on a printing paper surface to be printed and ejected to prevent printing ink from settling over the paper surface. Powder spraying means 1 for spraying powder, powder spraying quantity initial setting means 2 for initial setting of powder spraying quantity, powder spraying quantity detecting means 3 for detecting powder spraying quantity as an actually measured value, and powder spraying means 1. A powder spray amount adjusting means 4 such as an opening / closing valve for adjusting the powder spray amount; and a print area, print color number, print density,
An initial setting value conversion storage unit 5 for storing in advance a storage table for converting printing specification data such as printing paper quality and printing pressure into the initial setting value of the powder application amount, and the converted initial setting value and the powder application amount. And a control means 9 comprising: a comparison determining section for comparing the measured value with the actual measurement value; and a powder applied amount control section for controlling the operation of the powder applied amount adjusting means 4 based on the comparison / determination signal from the comparison / determining section. A powder spray device for a paper discharge section of a printing press.

(Operation of the Invention) The present invention is to store in advance before printing based on printing specifications (printing conditions such as printing image area, printing color number, printing image density, printing ink density, printing paper quality, printing pressure, etc.). The powder spraying device automatically operates the powder spraying amount adjusting means based on the initial setting value of the appropriate amount of powder sprayed by the put powder spraying device, and the powder spraying device is operated, so that the initial setting of the powder spraying amount is easy. is there. Also,
The powder spray amount adjustment means is measured by actually measuring the powder spray amount obtained by the operation based on the initial set value, comparing the initial set value with the actual measured value, and always making the actual measured value equal to the initial set value. It can be operated to automatically correct the spray.

(Examples) The present invention will be described in detail according to examples.

FIG. 1 is a block diagram of the apparatus of the present invention, in which an initial setting means 2 includes a storage unit 5 which previously stores signal data for setting a predetermined powder application amount as a storage table. For example, the storage table is as shown in Table I below, and the image area% on the horizontal axis is an ink image in which printing ink adheres to the surface of one sheet of printing paper (1 m ² ) printed according to a certain printing specification. The printing ink film thickness (μm) on the vertical axis indicates the average ink film thickness of the ink image to which the printing ink adheres. And it shows the amount of powder applied (mg) in that case.

However, Table I above is an appropriate value for a certain printing paper quality,
Initial setting values are not limited to the above table.

In this way, the initial setting means 2 causes the storage unit 6 of the control means 9 to store the initial setting data X (mg) for performing printing with the predetermined printing ink image area and printing ink film thickness. The data in the storage unit 6 is read by the control unit 8 via the arithmetic unit 8a, and the initial setting data X
First, the powder spray amount adjusting means 4 (for example, an opening / closing valve which is driven by a servo motor or a pulse motor equipped with an encoder) is operated to adjust the spray amount provided in the powder spray device 1. The opening degree of the means 4 (opening / closing valve) is set to the opening degree corresponding to the setting data X (mg). Spray the powder on top. The powder spread amount detecting means 3 detects the actually measured powder spread usage amount (the amount of powder decrease ΔWmg in the powder replenishing container) from the start of printing operation. On the other hand, from the number of prints S during that time,
Actual amount of powder sprayed per sheet of printing paper ΔW / S = x mg
Is calculated by the calculation unit 8a and is temporarily stored in the storage unit 6. This is obtained by printing a certain number of printed sheets (for example, about 50 sheets) after the start of the printing operation. Then, the storage unit 6
The comparison unit 7 compares the initial setting data X stored in the storage unit with the actual usage amount x, and based on the control signal of the control unit 8 which issues a control command signal based on the comparison result, the powder of the powder spraying means 1. The powder spraying means 1 is operated by operating the spray amount adjusting means 4 and adjusting the opening of the valve or the like of the adjusting means 4 so that the actual powder usage amount x becomes x = X.

FIG. 2 is a schematic side view of the powder spraying means in the apparatus of the present invention.
And a mixing container 14 for powder and air that communicates via a supply pipe 22 at the lower part of the container. The replenishing container 11 is filled with a powder p, and a powder level detector 12 for detecting a decrease (variable level) due to the use of the powder p.
Is provided. The powder p in the supply container 11 falls under its own weight, and is supplied to the mixing container 14 through the supply pipe 22. A predetermined amount of mixing powder p1 is stored in the supply pipe. 25 is a level sensor of the mixing powder.

The supply pipe 22 includes a solenoid 16 that reciprocates each time a sheet of printing paper 24 passes, an on-off valve 16a that opens and closes by reciprocating drive of the solenoid 16, and a powder spraying amount below the on-off valve 16a. Adjusting means 4. The means 4 includes an opening / closing valve 4c screwed from the side of the supply pipe 22 at the tip of a rotating shaft 4b that is driven to rotate by a micromotor 4a or the like, and the opening / closing valve 4c enters the supply pipe 22 and retreats. The opening degree of the supply pipe 22 can be set by the operation. The mixing vessel 14 has an air supply pipe 19 at the top and an air discharge pipe.
21 is provided. An open / close solenoid valve 17 is provided upstream of the air supply pipe 19.
And an air supply pipe 18 for blowing air a from the blower 13 into the mixing vessel 14 with a predetermined jetting power. The solenoid valve 17 is opened each time one sheet of printing paper is printed and discharged,
While blowing up a predetermined amount of mixing powder p1 in the mixing container 14, the powder p1 and the air a are mixed,
The air a1 mixed with the powder p1 passes through the discharge pipe 21 and is ejected from the spray nozzle 15 on the downstream side of the air discharge pipe 21. Outside the nozzle 15, a nozzle outer tube 15a
And an air supply pipe 20 for supplying air a from the blower 13 to the nozzle outer pipe 15a. From the air discharge pipe 21 side, every time the sheet-fed printing paper 24 passes below the nozzle 15, the electromagnetic valve 17 is operated to intermittently release air.
a1 is ejected from the nozzle 15. The on-off valve 16a is at the same phase timing as the opening operation of the solenoid valve 17, or
The opening operation is performed at the opposite phase timing. Thus, every time the printing paper 24 passes through the position facing the nozzle 15 from the nozzle 15, the powder mixed air 1a
And air a continuously ejected from the air supply pipe 20 side together with the air from the air ejection port 15b of the nozzle 15.
The powder p1 is sprayed onto the printing paper 24 on which the printing ink 23 has been transferred by being ejected from the position 5 and passing the position facing the air outlet 15b in the direction of the arrow. The powder spraying means is installed in the middle of the conveyance path of the printing paper in the paper discharge section of the sheet-fed printing press, and the blower 13 starts at the same time as the operation of the printing press, and in synchronization with the rotation of the printing press, The on-off valve 16a and the solenoid valve 17 are designed to open and close intermittently.

In the present invention, the replenishing amount of the powder p in the powder replenishing container 11 into the mixing container 14 is defined as the actual amount of powder used. Further, in the present invention, the supply amount of the air a by the blower 13 is always constant.

Initial setting data X (mg) set before starting printing operation
Indicates that the powder supply container 11 to the mixing container 14
Is the ideal amount of powder to be replenished, but in fact, the initial setting data X (mg) may not be replenished. The actual usage is detected by the level sensor 12.

FIG. 3 is a flowchart for explaining the operation of the apparatus of the present invention. If the operation of the apparatus of the present invention is described according to the flowchart, an initial setting value X is set in advance before printing is started. Subsequently, the operation of the sheet-fed printing press is started, and at the same time, the powder spraying means 1 is started. Subsequently, detection of the powder application amount x is started, and detection is continued for the detection duration T = t to detect the actual application amount x (actual powder usage amount). Subsequently, a comparison between the initial set value X and the actual spray amount x is performed. X = x
If so, the detection of the actual powder application amount x is repeated again.
If X <x, the amount of powder replenishment from the supply container 11 is suppressed by operating the powder amount adjusting means 4 in the closing direction. On the other hand, if X <x (if X> x), the powder amount adjusting means 4 is operated in the opening direction to increase the powder supply amount from the supply container 11, and the detection of the actual powder application amount is performed again. Start. By repeating the above operation, the amount of powder spray is controlled in a direction that approximates the initial set value X as much as possible.

The suppression amount, or the adjustment amount for each time in the repetitive control operation of the increase, may be a control operation of no replenishment and a constant small amount of replenishment, respectively, or, in an analog or digital manner, the opening degree of the on-off valve 4a. You may make it control.

(Effects of the Invention) The present invention provides a method for spraying a set-off preventing powder onto printing paper that is printed and discharged by a sheet-fed printing press.
Automatically, so that you can get the proper amount of spraying set in advance,
The powder spraying means can be controlled to operate, so that an appropriate amount of powder can be sprayed without the amount of powder being sprayed being too large or too small.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the structure of the apparatus of the present invention, FIG. 2 is a schematic side view of an embodiment of a powder spray means in the apparatus of the present invention, and FIG. 3 explains the operation of the apparatus of the present invention. It is an operation flowchart. 1 ... powder spray means, 2 ... initial setting means, 3
... powder spraying amount detecting means, 4 ... powder spraying amount adjusting means, 4a ... micromotor, 4b ... ... rotating shaft, 4c ...
... On-off valve, 5 ... Initial setting value selection data storage unit, 6 ...
Calculation data storage unit 7, comparison unit 8, control unit 8a
Calculation unit 9, Control means 10, Display unit 11, Powder supply container 12, Powder level sensor 13,
... Blower, 14 ... Mixing container, 15 ... Spray nozzle, 15
a ... Nozzle outer tube, 15b ... Spout, 16 ... Solenoid,
17… Solenoid, 17a… On-off valve, 18 …… Air supply pipe, 19 …… Air supply pipe, 20 …… Air supply pipe, 21 ……
Air discharge pipe, 22 ... Supply pipe, 23 ... Printing ink, 24 ...
… Printing paper, 25… powder level sensor, a… air, a1… powder mixed air, p… replenishing powder, p1… mixing powder

Claims (1)

(57) [Claims] 1. A powder spraying apparatus for a paper ejection section of a printing press for ejecting a powder of silica or the like sequentially onto a printing paper surface to be printed and ejected to prevent printing ink from settling over the paper surface. Spraying means, powder spraying amount initial setting means for initial setting of powder spraying amount, powder spraying amount detecting means for detecting powder spraying amount as an actual measurement value, and opening / closing valve for adjusting the powder spraying amount of the powder spraying means The printing specification data such as the printing area, the number of printing colors, the printing density, the printing paper quality, and the printing pressure, which are input and set from the powder spraying amount adjusting unit and the powder spraying amount initial setting unit, are converted into the initial setting value of the powder spraying amount. The initial setting value conversion storage unit that stores in advance a storage table for performing the conversion and the converted initial setting value and the powder application amount. A control unit comprising a comparison determination unit that compares the measured value and a powder application amount control unit that controls the operation of the powder application amount adjustment unit based on a comparison determination signal from the comparison determination unit. A powder spray device for the paper ejection section of the printing press.