JPS6058535A - Printing error detecting method - Google Patents

Abstract

PURPOSE:To judge printing error when the computed value exceeds the measured value, by obtaining the difference between a reference value and the amount of light reflected from the surface of paper to be detected at each measuring point, and designating the part, in which error points are continued, an error block. CONSTITUTION:A digital signal from an AD converter 13 is stored in a memory circuit 75 for each measuring point in accordance with the instruction of a memory controller 14. The content of a memory 16 is compared with the content of a memory 15 by a poor-level and poor-point detector 31. When the difference exceeds a specified poor-level or poor-point, the signal is detected as the poor- point. An operator 50 is provided in order to perform the computation of L+ S/P, where L is a peak value of an error block, S is the sum of the levels of the error block, and P is the number of error points in the error block. A part, in which the error points are continued is designated to be the error block. When the computed value exceeds the preset value, the error is judged.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting printing errors.

An object of the present invention is to provide a printing error detection method that can accurately detect printing errors.

The printing error detection method of the present invention shines light onto the paper surface, and the difference between (a) and (2) the foul light is determined by the difference between (a) and (printing).

The printing error detection method of the present invention is based on the signal of the standard 111i paper surface (preferably memorized), and compares this reference value with the signal of the detected paper surface to determine whether the printed surface is good or not. Determine.

Printing error detection method of the present invention (Jl) A plurality of points 1~ on the paper are taken as measurement points i~.At that time, a plurality of light receiving elements are arranged in a row, and the amount of electricity continuously transmitted from each light receiving element is measured. A large number of measurement points are obtained by time-division covering.

The comparison at each measurement point 1 was easily determined as "1 - [3 1' - 0"("1 is one point 1 ~" (vote '4')
If there are two rows of r((reflection of the surface 8, [1' (on the detected paper surface: ;';) and line 4r, there is a slight unevenness of the paper surface, and the error ZX position of the measurement point l~ (the thread of C7). 2, there is a risk that C-41\C will be determined to be defective. It seems that the outbreak will be reversed in J5, so let's do it.
[Insert it as a nonce (Osa, beyond this, I'
Judgment that there is 21-C in Ji is 1...J J,
Uniriru 1゜However, if the two printing surfaces are set as 8111, then I
f! rl IO) When comparing the measurement point 1-, an error number 11g may be generated at the other (I'!, J,-), and a Sierra signal may be output.

Therefore, in the present invention, the comparison is made at the same position as the paper surface and the point 1 is compared to the defective point 1.
Collect ~, 11, according to the difference of the points, the ratio of the number of defective points 1~ (also +J, /lゝnumber of error points in point 1-) is P119. constant' L, / (diξ), when the defective point exceeds this ratio (or number),
It is determined that the detected paper surface is a printing error.

However, another determination method may also be adopted. In other words, the difference between the standard value and the amount of foul light from the detection paper surface is taken for each measurement point, and the difference is calculated as the level arrow 1 nonce and /
Or error point 1 when exceeding point 1 to allowance
~, and set the continuous part to error point 1 as error point 1
-1 ivy and zuru 3, i and the next equation is 40'? do.

L + S / P (Here, To (J, Ellerbe I cock peak fi5i
, S is the sum of the levels of error No. 11g, and [] is the number of points of []]] of Niraburo and 1-. ) A printing error is determined when the number of tears in the above equation exceeds the measured value.

The embodiment shown in FIG. 1 will be explained. The vertical axis indicates the amount of foul light on the paper surface. Suke A indicates the level of the pure white paper, lll
1lIB is the level of the pitch-black paper.
([1) (c)..., (1~) is J
: Indicates the positions of multiple measurement points of one light-receiving element.
A large number of measurement points are distributed over the entire C1 printing surface of the camera.

For one light-receiving element - (only explanation (J tt is the signal 1001.
00a is a signal obtained by adding level) 1-1 tuns M to ImF3100, and signal 100b4, +C3'+
(') Subtract level horn once X+ from O, A, (1
'l'I'7'' (Yes.Measure the detected paper surface and believe;
'i 'I OOa and I.

If a measurement of a predetermined height j or more is entered between No. 1001) and India enters, the measurement paper is cut off at 1'11 if the printing is good at θj'.

Now, if the detected paper surface is a good print (regardless of whether there is a defect in the paper surface), the J, QJ quantification may be different, and it may be set as Print - L error, and 1: may occur. This J,
In order to avoid such discrimination mistakes (J), set correction level α to [1']
If we add or subtract E+ - (E+' ±α) to ±M and make a comparison, correct the difference between Mitsuhaku on the other side and reverse the judgment, it would be 12.

For example, if the detected paper surface is dark, the detected paper surface signal 101 (
1) approaches axis B as a whole. Believe as it is Q10
If we compare Q1 with Q100, the detected paper surface will be determined to be a printing error, so we add correction level α to Q101 and make the comparison with Q101 as Q51o1'.

Does this J-level allowance correspond to the paper quality, paper unevenness, and senri "-drift 1"?
Points 1 to 1, which will be explained next, are mainly used to deal with the misalignment between the print surface and the print surface. (h′ [zero value)
, and the point 1 hair L]once is the horizontal allowance (tolerance 1ii'j).

If level) Norowance and Point 1 to Allowance are set to exactly the same value, the allowable range is measurement point 1.
- to the center [becomes a bevel shape] Of course, level allowances and point 1 to allowances can be sentai to each other. In that case, both names may have different values, and it goes to the rectangular 11 volume range. Any of the once combinations (Figure 2) 1.1. ! If the zumbling data exceeds the allowance of plus or minus (31), the error pawn will be 1 degree and the next f number will be 71%.
Determine C printing 1 fu.

Judgment method (1) 仝Point 1-medium, 1-C point 1~
Because of this, the J seed is placed on the platform beyond the fixed position l + fj.

Judgment method <2)] Sea point 1 to 4-;

L + S / P 1- is the error block [Cock's peak (Direct S is the sum of the levels of error blocks P is] - Sea block's 2 [Seaboin 1 to a number below, referring to FIG. 4, the method of the present invention is Preferred implementation examples will be explained below.

The sensor section '1 detects the paper surface. N011...N
O, II 4J, Indicates the number of the optical lens relay J, that is, the light receiving element.

The sensor section 1 is installed and covered at a suitable location where the printing surface advances.

The sensor section 1 is constructed in such a way that the light from the light emitting element is reflected onto the surface of the paper, and the reflected light is converted into an optical element (light receiving element) into an analog or electrical signal.

The output of the sensor section 1 is amplified by an amplifier 2. lll
It is preferable that the single-width amplifier 2 is a buffer/amplifier that changes impedance in order to prevent noise from entering.

The amplified signal is sent to Multibrella 1-79. At Multi-Breakley-79, Anna 1' Gui 3 is time-divided and sequentially sent to AD] Nba Kui 13 via AI 1'-C 11.

The multi-block 79 is omitted, and each light receiving element No. 1~
11 △1] Point 11 - Set up a road block after Lar 1L - JC is also J, yes.

AD controller 111. L iit iit time 2 During the measurement pulse of the rollers 1 to 12, the horse mackerel [
I want to sample J-gu Shino / 1 1 1 Hearter 1
Send to 3. 11-12 (from starter 3 to fili'; my daughter-in-law Lus J, -) (
It works. Starter 31J: Attached to the power shaft of the printing machine, etc., it emits a signal pulse at the same time as starting the signal.

Sampling is performed in the form of a verse division, fj<r, on the pulse from EnT]-Gu1. The printer 4 can act as a power shaft for the printing machine 1.

The Δ1〕2'' converter 13 converts the 11 signal into a digital signal. According to the instructions, the memory circuit 7
5 for each measurement point.

The following will explain one optical sensor (light receiving element) as an example.

The memory circuit 75 is a standard memory 15 due to its role.
It can be determined that the detection memory is 1G. There is no functional difference between the standard memory 15 and the detection memory -16+; L 4tM. Merry-15 #, J, Muku single group j(r) U
) information, and the memory 16 stores information on the detected paper surface.

The operations of memory 15 and memory 16 are as follows.

The contents of the memory 16 are compared with the contents of the memory 15 by the level defect and point 1 to defect detector 31, and if there is a difference of more than a predetermined defect level or t;L defect point, it is detected as a defect point I. be done. Information on the first measurement point on the standard paper of memory 15 (hereinafter referred to as E)
l> is derived to the level failure and point 1 to failure detector 31. Subsequently, information on the first measurement point (~ (hereinafter referred to as E+') on the detection paper surface in the memory 16 is led to the level defect and point defect detector 31.I-(, level defect and point 1 information) to defective detector 3'I
(゛, E+-(E+'±α) < 18: By the determination of M, [■1' is judged whether there is a defective or defective in 1~(゛).

In this case (J, level y7 j'J once and po, in 1
~ j′ mouth 1 nonce is the same jlb, but both 81;
1. It may be a different value.

The correction level α is set arbitrarily by the correction level 1 imprinter 90-(-.For example, when there is no change in the paper quality of the standard paper,
Set level α to 0 7J.

Defective level and defective point 1 to M L, U defective level level determiner 32 J, 5Q is determined arbitrarily 3, defective level and defective point 1 separately +7 It is preferable to cover it so that it can be set.

If E+' is a failure signal, one pulse is sent from the level failure and point failure detector 31 to the failure rate detector 51. The defect rate detector 51 counts the number of pulses.

Next, information on the second measurement point on the standard paper (E2
) and the information of the second measurement point on the detection paper surface (E 2
')- are compared with the same J, and it is determined whether E2' is a defective signal or not.

This operation is performed for all measurement points 1-.

When the comparison is completed for the measurement points 1 to 1, the defective rate detector 51 stores the number of defective signals. Whether printing is defective or not is determined based on the ratio of the number of defective signals to the total number of measurement points. In other words, J
It is determined that .

The ratio of the defective signal to the total number of measurement points is set in the defective $ setter 42.

For example, when the failure rate setting device 42 is set to 20%, the total measurement points 1- are 10 + j, t and 2 points are the limit for the number of failures 8. This 2 Ill") information is sent from the defective rate setter 42 to the defective rate detector 51. The defective rate detector 51 stores the number of defective signals (g) and the defective rate. The information sent from the setter 42 is compared with the information sent from the setter 42, and sent to the continuous failure occurrence detector 61, which determines whether the detected ifI is suitable for printing.

FX setting device 4 to the failure level and failure point 1.
It is also possible to set the defective rate in accordance with φ/I.

In addition, as shown in FIG.
2 and the defective rate detector 51 are omitted, and instead of the above-mentioned 1.
．． - I-S / +1 to 61 cuts 1 ii,! j pull 1
:P', 50 may be set and the above-mentioned determination method (2) may be performed.

In order to be compatible with high-speed printing presses, the zumbling time at each measurement point 1 to 1 must be as short as possible, but the above-mentioned allowance (tolerance) must be kept at all points 1.
When ~ is stored in the C memory, r d3 <, IJI → non-pull, comparison and determination processing become faster at each point, and the processing speed improves.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the principle of the printing error detection method of the present invention, and Fig. 2 shows the relationship between the reference value and the level [1 once].
Figure 3 shows the standard value, level allowance, and points 1~
FIG. 4 is a block diagram showing an example of implementing the printing method of the present invention. 1... Sensor part 2... Amplifier 13... AD converter 14... Memory controller 1 to roller 15... Standard memory 16... Detection meter - 31... Level failure and Point 1 - defective detector 32 ... defective part and point 1 - defective detector ii,
Q determiner 42...Failure rate setter 50...Densifier I unit 51...Failure rate detector 90...Correction level setter Patent applicant Co., Ltd. (Meeting 1 Hokuden I' Agent) Person Patent Attorney T, "1"'+' Jl Toru Figure 1 Figure 3 Procedural Amendment (Voluntary) October 1982) Japan Patent Office Commissioner Kazuo Wakasugi 1, Indication Patent No. 01358-1 66942 2, Detection method for printing errors in the name of invention 3, person making amendment, case and relationship Patent applicant address: 28-6 Iwabuchi-cho, Kita-ku, Tokyo Name: Kita Denshi Co., Ltd. 4, Agent address: 2-8-1 Toranomon, Minato-ku, Tokyo Drawing 7, details of amendment The official drawing has been corrected as shown in the attached sheet. No changes to content. Procedure for amendment (method) % formula % 1. Indication of the case Patent application 1982-166942 2. Method for detecting printing errors in the name of the invention 3. Person making the amendment What is the relationship between the case and special gamma [Applicant's address Kita-ku, Tokyo] 28-6 Kanbuchi-cho Name: Kita Denshi 4 Co., Ltd. Agent address: 2-8-1 Toramon, Minato-ku, Tokyo 5, Date of amendment order: January 110, 1980 (Shipped on January 31 of the same year) 5. Target of amendment: tlfJ7 in "Brief explanation of drawings" from Mei III, "Gura 11" in page 14, bottom line 1 of the detailed description of the amendment
Figure 5 shows another example of the r-gram, which is a rib block tie 17-gram.

Claims (2)

[Claims] (1) First, shine light on the marker i1 at multiple measurement points 1~ on the paper, measure the amount of reflected light at all measurement points, set it as a reference value, and measure the positive and negative level allowances from that standard (i1). Then, apply light to multiple corresponding measurement points on the detection paper surface, measure the amount of reflected light from the detection paper surface, and calculate the difference between the reference value and the amount of reflected light from the detection paper surface at each measurement point. When the ax exceeds the level allowance, it is set as an error point, and the point where sea points 1 and above are consecutive is set as an error mark [-], and L is set as an error point.
+ S / P (Here, L is the peak value of the error block, S is the sum of the levels of the error block, and P is the conicy point 1 to number of the error block) 4" to determine a printing error.
j i 歭と1ノRU 類 り] [Detection method of ra. (2) The leveler [l once and the point