JPS62216087A - Reading method for identification number - Google Patents

Abstract

PURPOSE:To avoid erroneous read based on the trouble or the like of sensors and to improve the reliability of read by using sensors whose number is larger than the number of all bits by one and shifting the read position to read data again after data is read once and collating read results. CONSTITUTION:In the first read, the detection of n-number of bits b1-bn and a point A which is a length P distant from the left end bit b1 in the left direction is performed. At this time, a sensor S1 faces the point A and outputs '0' certainly, and sensors S2 and S(n+1) face a start hole and an end hole respectively and output '1' certainly. Sensors S3-S(n-1) output '1' or '0' in accordance with the code of an identification number. The read result is stored in a memory. In the second read, a point B which is the length P distant from the bit bn in the right direction is detected to read the code similarly. It is checked whether a code reader is arranged correctly or not in accordance with output signals of points A and B or the like, and the coincidence between bits for two serial number displays is checked.

Description

[Detailed description of the invention] [100th] - Overview - Field of industrial application - Prior art - Problems to be solved by the invention - Means for solving the problems - Effects - Examples - Effects of the invention [Summary] Using the total number of bits + 1 sensor, read twice by shifting the correspondence between each bit and sensor by 1 pitch, and check the reading by comparing the reading results to check the reliability of the reading. An identification number reading method with improved performance.

[Industrial application field]

The present invention relates to a method for reading an identification number in which the product number, manufacturing number, etc. of an article is coded and displayed.

[Conventional technology]

In the manufacturing process of printed circuit boards, etc., in order to display serial numbers such as the product number and serial number of the printed circuit board, holes with a constant pitch are formed on the side edge of the printed circuit board.
” is formed. When reading such a serial number, a code league having a number of sensors equal to the total number of bits is used to simultaneously detect all bits and read the code.

[Problem that the invention seeks to solve]

With conventional methods of reading identification numbers such as serial numbers, there is a possibility of erroneous readings due to failure of the code league sensor, etc., and there is a problem with the reliability of reading. In the case of such a sensor failure, even if the reading operation was repeated twice to confirm the number, the result was the same and it was not possible to avoid misreading.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and it is an object of the present invention to provide an identification number reading method that avoids erroneous readings due to sensor failure, etc., and improves the accuracy of readings.

(Means for solving the problem) In order to achieve this object, in the present invention, l" or "0
``In an identification number reading method that displays an identification number by providing a level encoding means and reads the identification number using a sensor that determines the ``1'' or ``0'' level of each bit, Arranged (n+1)
The sensors simultaneously determine "1" and "0" at positions outside the n bits and the bit at one end by a distance [P, and then each sensor is shifted by 1 pitch to determine the n bits and the opposite side. It is characterized in that it discriminates between "1" and "0" at a position a distance P from the end bit, and performs a reading check by comparing the above two discrimination results.

[For production]

The code league has the total number of bits plus one sensor, and the code league is read twice by shifting the code league by one bit to change the combination of the sensor and the bit. Only when the results of the two readings are compared and there is a loss, the Code League will issue a reading output.

〔Example〕

The procedure of the method of the present invention will be explained with reference to FIG.

n bits bl"bn are provided at a constant pitch p on the side edge of the printed board P. Each bit tzxbn is
'', a semicircular hole is formed as a means of encoding "O", and "I" depending on the presence or absence of the hole.

“0” is determined. Bits b and bn at both ends are always provided with holes as a start hole and an end hole. second bin from the right) b (n-1)
are check parity bits, and the remaining central bits b2 to b (n-2) are number display bits. Parity bit b (n-1) is adjusted so that the number of holes in all bits is always an odd number, for example. That is, if the number of bits with holes formed among the number display bits bt~b (n-2) is an even number, the parity bit b
A hole is formed in (n-1), and if the majority of number display bits is an odd number, no hole is formed in the parity bit.

By detecting this parity bit, it is possible to check the detection result as to whether the large number of number display bits detected by the sensor is an even number or an odd number. A code league (not shown) for reading such code numbers has (n
+1) sensors S, ~S(n+1) are arranged at a pitch p that is the same as the bit pitch. Each sensor may be any sensor capable of detecting holes, such as a transmission type photo sensor, a reflection type photo sensor, a proximity switch, or a microswitch.

Using a code league having such (n+1) sensors, first, as shown in the figure, n bits) b+ ~bn and A that is P away to the left of the leftmost bit b1 are read as the first reading. Perform point detection. As a result, output signals of "1" for Obu and "O" for Daikoku are obtained from each sensor depending on the presence or absence of a hole. At this time, S,
is point A, which is always “0”, S2 and S (n+1)
are the start hole and end hole and must be “1”
, Sn are parity bits and are predetermined "1" or "01". Also, S3 to S (n-1) are each "engine" according to the code of the identification number (serial number).
or O''. This output signal is input to the memory circuit.

Next, a second reading is performed. In this case, as shown in the figure, the code league is shifted to the right by one pitch from the first reading, and n bits tz~bn and the rightmost bit b are
Point B, which is located a distance P to the right of n, is detected. At this time,
S (n+1) is point B and must be 0", S and Sn are the start hole and end hole and must be "
1', S (n+1) is a parity pit and is the same "work" or "0" as the first time. Also 82~S (n-2
) corresponds to the identification number and is the same “1” or “O” as the first time.
”.

The above reading results are shown in the table.

In each of the first and second detections, the output signals of point A, point B, start/end hole, and parity pit are used to check whether the state of the sensor and the arrangement of the code league are appropriate.

It is also checked whether the output signals of the display bits bz-b (n-2) of the first and second serial numbers match. If all the verification check results are correct, the code league will issue a read output signal.

〔Effect of the invention〕

As explained above, in the identification number reading method according to the present invention, reading is performed twice using the total number of bits + 1 sensor with the reading position shifted, and the reading results are compared. Therefore, the reading check is performed reliably and the reliability of the reading is improved.

[Brief explanation of drawings]

FIG. 1 is a procedural explanatory diagram of the method of the present invention. P...Printed board, h...hole. SI S2 S3 St, 55 S6
S(r+-+)Sn S(rm1 Procedure explanatory diagram of the method of the present invention Fig. 1

Claims (1)

[Claims] 1. An identification number is displayed by providing a "1" or "0" level coding means at n bit positions provided at a constant pitch p on the article, and each bit's " In an identification number reading method in which the identification number is read using a sensor that discriminates between ``1'' and ``0'' levels, n bits and one end are simultaneously read by (n+1) sensors arranged at the pitch p. Distinguish "1" and "0" at the outer position by distance P from the bit, and then shift each sensor by 1 pitch to detect "1" and "0" at the outer position by distance P from n bits and the bit at the opposite end. 1” and “0”, and perform the above 2.
An identification number reading method characterized by performing a reading check by comparing the discrimination results twice. 2. The identification number reading method according to claim 1, wherein the encoding means is an opening provided on the article at the bit position. 3. The identification number reading method according to claim 2, wherein openings are always provided at the bit positions at both ends.