JPH06316136A - Printer - Google Patents

Abstract

PURPOSE:To apply printing only to a blank paper surface, in a printer such as a cosier or a terminal printer, by automatically discriminating the blank paper surface of supplied printing paper. CONSTITUTION:A paper storing part 1 storing printing paper, a paper processing part 2 taking in the paper from the paper storing part and a printing processing part 3 printing an image on the paper supplied from the paper processing part are provided. The paper processing part 2 has function discriminating whether the taken-in paper has a blank paper surface, function supplying the paper to the printing processing part in a direction applying printing to the blank paper surface when it is discriminated that the paper has the blank paper surface and function discharging the paper without printing the same when it is discriminated that there is no blank paper surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus applied to, for example, a copying machine or a terminal printer of a computer, and more particularly, to a printing apparatus for reusing a sheet having one side already printed as a printing sheet. The present invention relates to a printing device with improved convenience.

[0002]

2. Description of the Related Art In recent years, the importance of reusing resources has been recognized, and even in a general office, in a printing apparatus such as a copying machine or a terminal printer, a sheet already printed on one side is reused to make a back side. There are more and more cases where printing is done.

In such a case, in the conventional printing apparatus, the used paper is first manually selected from the used papers having a blank surface, and the selected papers are aligned so that the blank surface is printed. It is necessary to go through the work of storing it in the printing device.

[0004]

However, since such manual work is troublesome, many people are not willing to recycle used paper.

Further, when the papers already printed on both sides are mixed in the papers manually selected, there is also a problem that double printing is performed on the already printed surface.

Furthermore, since one side is newly printed on the back side of a sheet on which printing has already been performed, print results will eventually exist on both sides of the sheet, making it difficult to know which side is the new printing side. There are also problems.

Therefore, a main object of the present invention is to automatically determine the blank surface of the supplied printing paper in a printing apparatus such as a copying machine or a terminal printer and perform printing only on the blank surface. In addition, if paper that has already been printed on both sides is supplied, it is automatically excluded from the printing paper, so that paper that has already been printed on one side can be efficiently removed without human intervention. To make it reusable.

A further object of the present invention is to make it possible to easily identify the newly printed surface when the new printing is made on the back surface of a sheet having one side already printed.

[0009]

SUMMARY OF THE INVENTION A printing apparatus according to the present invention includes a paper storage unit for storing print paper, a paper processing unit for loading paper from the paper storage unit, and a paper supply unit for each paper supplied from the paper processing unit. And a print processing unit that prints an image. Then, the paper processing unit determines whether or not each of the taken-in papers has a blank surface, and, when the blank surface determination means determines that there is a blank surface, prints on this blank surface. When the blank surface setting unit that supplies the paper to the print processing unit and the blank surface determination unit determines that the paper has no blank surface, the paper that is ejected so that printing is not performed on the paper Have with reject means.

Further, it is desirable that the paper processing unit further comprises mark giving means for putting a mark on the surface of the printing paper which is judged not to be a blank surface.

[0011]

In the printing apparatus of the present invention, the paper to be printed is first checked whether or not there is a blank surface, and if there is a blank surface, printing is performed on the blank surface. The print sheet is supplied to the print processing unit. If the printing paper has no blank surface, the paper is ejected without printing.

Therefore, when the printed paper is reused,
There is no need for the troublesome work of manually removing the paper that has been printed on both sides or aligning the blank surface of the paper in the printing device.

Further, in the apparatus which performs marking on a paper surface other than the blank paper surface, it is possible to easily identify which surface of the printed printing paper is the newly printed surface.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the printing apparatus of the present invention.

As shown in FIG. 1, the printing apparatus 1 includes a printing paper storage unit 2 for storing printing paper, and printing papers taken in from the printing paper storage unit 2 one by one and sent to a printing processing unit 3. It comprises a processing unit 2 and a print processing unit 4 that prints on the print paper supplied from the print paper processing unit 3.

Here, the print sheet processing unit 2 has a function of detecting a blank side of the fetched print sheet, and a function of discharging the double-side printed sheet having no blank side without printing. For a print sheet with a blank side, the function of aligning the blank side of the print sheet in a certain direction and supplying it to the print processing unit 3 so that printing is performed on the blank side, and for a sheet with one side printed, It has a function of attaching a predetermined mark to the printed surface.

The functional configuration of the print sheet processing unit 2 will be described in detail below.

FIG. 2 is a block diagram showing the functional arrangement of the printing paper processing unit 3.

As shown in FIG. 2, the print sheet processing unit 3 is
A black area detection unit 21, a white paper surface determination unit 22, a white paper surface setting unit 23, and a print paper reject unit 24 are provided.

The black area detection unit 21 detects the black areas of the front and back surfaces of the printing paper sent from the printing paper storage unit 2, and indicates the position and size of the detected black area on the paper surface. The information is sent to the blank page discrimination unit 22. Here, the "black area" means an area that has a color substantially the same as the print color on the paper surface, and in the present embodiment, assuming a normal case of printing black on a white background paper, " Although referred to as a "black" area, when the printing color is other than black or in the case of multicolor printing, it refers to the area of the color corresponding to the printing color.

The blank page discrimination section 22 discriminates which side of the printing sheet is a blank page based on the black area information from the detection section 21.

The blank page setting section 23 includes a blank page determination section 22.
According to the result of the judgment, if the blank side is on the side to be printed, the print sheet is in the same direction as it is. Send to Part 4. As a method of turning over the printing paper, a method of sending the printing paper to a roller and making a U-turn is common.

The printing paper rejecting unit 24, when the result of the judgment by the blank paper surface judging unit 22 indicates that there is no blank paper surface,
The print sheet is discharged without being sent to the print processing unit 4.

FIG. 3 shows a functional configuration of the above-mentioned black area detecting section 21.

As shown in FIG. 3, the black area detecting section 21 includes
A black area sensor 31 and a black area information table 33 are provided. The black area sensor 31 detects the black areas existing on the front and back surfaces of the printing paper sent from the printing paper storage unit 2, and the black area information 32 indicating the size and the position of the black area.
To generate. The black area information 32 is recorded in the black area information table 33.

FIG. 4 shows the functional configuration of the blank page discrimination unit 22 described above.

As shown in FIG. 4, the blank page discrimination section 22
The black area information evaluation unit 41 and the judgment result table 44 are provided. The black area information evaluation unit 41 applies the black area information 32 recorded in the black area information table 33 shown in FIG. 3 for each paper surface to the black area information evaluation formula 42 prepared in advance, so that each paper surface It is determined whether the page is blank. The judgment result 43 is recorded in the judgment result table 44.

An example of the black area information evaluation formula 42 is shown below.

[0030]

[Formula 1]

Here, αn is a weighting coefficient determined as a function of the square of the distance of the black region n from the paper center, Ln is the size of the black region n, and T is a threshold value. The weighting factor αn and the threshold value T are selected so that this evaluation formula is satisfied only when the black area does not exist near the center of the screen and the large black area does not exist on the paper surface.

When the black region existing on the paper surface is within the range where this evaluation formula is satisfied, it is determined that the paper surface is a white paper surface.

FIG. 5 shows a functional configuration of the above-mentioned blank page setting section 23.

The blank page setting section 23 includes a process determining section 51,
A setting unit 52 and an old printing surface notification symbol printing unit 53 are provided. The process determination unit 51 determines the content of the process to be performed on the print sheet according to the determination result 43 recorded in the determination result table 44.

This decision is made according to the process decision table 54 shown in FIG. It should be noted that in FIG. 7, the A-side indicates the paper surface facing the printed side, and the B-side indicates the surface facing the non-printed side.

As shown in FIG. 7, when both sides (side A and side B) of the printing paper are blank, no special processing is performed and the printing paper is sent to the printing processing unit 4 in the same direction. If the A side is blank and the B side is printed, B
Print a mark on the side to indicate that it has been printed, and
The printing paper is sent to the printing processing unit 4 in the same direction so that printing is performed on the A side. On the other hand, side A has already been printed,
If the B side is blank, a mark indicating that printing has been completed is printed on the A side, and then the printing paper is turned over and sent to the print processing unit 4 so that the B side is printed. Further, when both sides A and B have been printed, a reject process described later is performed.

Referring again to FIG. 5, the setting unit 52 prints the printing paper that has been sent to the printing processing unit 4 according to the above determination, in the same direction as it is, or after turning over the printing processing. Send to Part 4. In addition, the old printing surface notification symbol printing unit 53 prints a predetermined mark indicating that printing has been completed on a paper surface other than a blank paper surface according to the above determination. For example, an X mark is printed on the entire print surface.

FIG. 6 shows the above-mentioned printing paper rejecting unit 24.
The functional configuration of is shown.

In FIG. 6, the reject processing unit 61 is
When the reject process is determined by the above-described process determination, the print sheet is discharged outside the printing apparatus without printing, and a signal indicating that the sheet is discharged is sent to the next sheet supply 62. The next paper supply unit 62 takes in the next print paper from the print paper storage unit 2 in response to the signal from the reject processing unit 62.

FIG. 8 is a flow chart showing the operation of the printing apparatus having the above-mentioned configuration.

First, one sheet of printing paper is fed from the printing paper storage unit 2 to the printing paper processing unit 3 (step 81). In the printing paper processing unit 3, the black area detecting unit 21 checks the black areas on both sides of the sent printing paper (step 8).
2) Based on the above-described evaluation formula, it is determined whether or not there is a blank surface on the printing paper (step 83).

When neither side of the printing paper is blank, the printing paper is unsuitable for printing and is ejected from the printing apparatus 1 (step 87), and a new printing paper is immediately taken in from the printing paper storage 2 (step 88). ).

When it is determined in step 83 that there is a blank surface, it is determined whether or not there is an already printed surface (step 84). If there is an already printed surface, that surface, for example, A mark such as a cross mark is attached (step 85), the direction of this paper is adjusted so that it can be printed on a blank surface, and the paper is sent into the print processing unit 4 (step 8).
6).

On the other hand, when it is determined in step 84 that both sides of the printing paper are blank, the printing paper is sent to the print processing section 4 as it is (step 89).

Printing is performed on the printing paper thus sent to the printing processing unit 4 (step 90).

Although the preferred embodiment of the present invention has been described above, the scope of the present invention is not limited to the above embodiment, and the configuration can be arbitrarily changed without departing from the scope of the invention. .

For example, in the evaluation formula used in the above embodiment, the weighting factor is not defined as a function of the distance from the center of the paper surface as in the embodiment, but the weighting factor of the peripheral area in the paper surface where printing is not generally performed. Alternatively, the former may be set to be smaller and the latter may be set to be larger by dividing into other weighting factors of the area to be printed in general. In such a case, even if there is some black area in the peripheral area, if there is substantially no black area in the other area, it is determined to be a blank page.

Further, in the above embodiment, the blank surface check of the paper, the adjustment of the paper orientation, and the removal of the non-printable paper are performed when the print processing is performed, but these processings are executed when the print processing is not performed. Then, the blank surfaces of all the sheets may be aligned in a certain direction in advance. In such a case, at the time of printing, the work of turning over the paper and discharging the paper on which double-sided printing has been performed is eliminated, so that the throughput is improved.

Further, in order to improve the throughput and reduce the cost of the apparatus, printing is performed only on the paper whose side A is blank and the paper whose side B is white is the same as the paper that has been printed on both sides. It may be discharged to. This eliminates the need for a paper reversing mechanism, which simplifies the structure of the device and lowers the cost. Moreover, most of the paper is stored in the device because the A side of most of the paper is a blank surface. It is practical enough to be careful so that

[0050]

As described above, according to the present invention,
Before printing on the printing paper, detect the blank side of the printing paper and send the printing paper to the print processing section so that printing is performed on the blank side. In addition, since the printing paper is discharged without printing, it is possible to print only on the white paper surface of the used paper without manpower.

Further, by providing a mark on the already printed surface of the paper, it is possible to easily identify the newly printed surface.

Due to these effects, the present invention can contribute to resource saving.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a printing apparatus of the present invention.

FIG. 2 is a block diagram showing a configuration of a print sheet processing unit of the embodiment.

FIG. 3 is a block diagram showing a configuration of a black area detection unit of a print sheet processing unit.

FIG. 4 is a block diagram showing a configuration of a blank sheet surface determination section of the print sheet processing section.

FIG. 5 is a block diagram showing a configuration of a blank surface setting unit of the printing paper processing unit.

FIG. 6 is a block diagram showing a configuration of a print sheet reject unit of the print sheet processing unit.

FIG. 7 is a processing determination table that determines processing of paper in a blank page setting unit.

FIG. 8 is a flowchart showing the operation of the embodiment.

[Explanation of symbols]

 1 Printing Apparatus 2 Printing Paper Storage Section 3 Printing Paper Processing Section 4 Printing Processing Section 21 Black Area Detection Section 22 White Paper Surface Discrimination Section 23 White Paper Surface Setting Section 24 Printing Paper Rejection Section 31 Black Area Sensor 32 Black Area Information 33 Black Area Information Table 41 Black Area Information Evaluation Section 42 Black Area Information Evaluation Formula 43 Judgment Result 44 Judgment Result Table 51 Processing Decision Section 52 Set Section 53 Old Printing Surface Notification Symbol Printing Section 54 Processing Decision Table 61 Rejection Processing Section 62 Secondary Paper Supply Section

[Equation 1]

Claims (6)

[Claims] 1. Printing comprising a paper storage unit for storing print paper, a paper processing unit for loading the paper from the paper storage unit, and a print processing unit for printing an image on each paper supplied from the paper processing unit. In the apparatus, when the paper processing unit determines that each of the taken-in papers has a blank surface, and a blank surface determination means determines that the paper has a blank surface. , A blank surface setting means for supplying the paper to the print processing section in a direction such that printing is performed on the blank paper surface, and the blank paper surface determination means judges that the blank paper surface does not exist And a sheet rejecting unit for ejecting the sheet without printing it. 2. The printing apparatus according to claim 1, wherein the white paper surface determination unit detects a black area on each of front and back surfaces of the paper, and a black area detection unit. A printing apparatus comprising: a black area evaluation unit that evaluates whether or not each of the front surface and the back surface is a blank surface by evaluating the information of the detected black area using a predetermined evaluation formula. 3. The printing apparatus according to claim 2, wherein the evaluation formula is a weighting coefficient according to a position of each black area detected from one paper surface on the paper surface, and a size of each black area. The evaluation amount of each of the black areas is obtained from the above, the evaluation values are integrated for all the detected black areas, and it is determined whether or not the paper surface is a blank paper surface based on the integrated value. A printing device characterized by being. 4. The printing apparatus according to claim 1, wherein when the blank page setting means is not on the side on which the blank page is printed, the sheet is turned over so that the blank page is on the printed side. The printing apparatus supplies the print processing unit to the print processing unit. 5. The printing apparatus according to claim 1, wherein the blank page setting unit discharges the sheet without printing when the blank page is not on the side where the blank page is printed. Printing device. 6. The printing apparatus according to claim 1, wherein the paper processing unit further includes mark giving means for putting a mark on a paper surface which is judged not to be a blank surface by the blank paper surface determining means. Characteristic printing device.