JPH0367105A - Small hole position detecting device - Google Patents

Abstract

PURPOSE:To improve the detection accuracy by judging whether or not a small- hole detection signal is generated normally at a small hole position when the small-hole detection signal is generated from the video signal of an image sensor and the two-dimensional address of the small hole is detected. CONSTITUTION:When a black area 18a is scanned, an H-level video signal pulse (a) is generated and a monostable multivibrator 11 generates a pulse signal P12 at the point of time of lightness variation from black to white; when the pulse (a) is inputted to a NAND gate 10, an AND signal P13 is outputted. Then when the signal P13 is present in an output signal of neither the gate 10 nor a shift register(SR) 24 and a signal corresponding to a signal P13 is present at all SRs 21 - 23, a small-hole preliminary detection signal (b) is outputted from an AND gate 28. This signal is supplied to a NAND gate 46, an SR 44 outputs a delay video signal pulse P0 corresponding to a pulse (a) which are four pulses precedent, and while a monostable multivibrator 45 does not generate a small-hole detection inhibition pulse PP at the point of time of the generation of the signal (b) is generated, the small-hole detection signal (c) is outputted from the gate 46. This signal (c) is passed through an address signal output circuit 33 and stored 39.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for detecting the two-dimensional address of a small hole surrounded by regions of different brightness on a plane such as a pattern film of a printed circuit board. The present invention relates to a position detection device.

[Prior art] Conventionally, drilling holes in printed circuit boards has been automatically performed using an NC device, but when attempting to drill holes after reading an arbitrary pattern, the two-dimensional position of the hole can be automatically detected. There was no equipment to do so.

Therefore, in Japanese Patent Application No. 63-201055, the present applicant scanned the plane l in a line in FIGS. In response to the image sensor 2 and the video signal pulse P obtained by binarizing the video signal according to the change in brightness, a line scanning time corresponding to a line scanning time slightly wider than the diameter of the small hole 8 is generated at the leading edge of the small hole 8. Pulse P2 with a time width of
The pulse generating means 3a that generates the pulse P2 and the video signal pulse P, and the AND means 3 that receives the pulse P2 and the video signal pulse P, time delay means 4 for time-delaying the output signal of the AND means 3 for the new scan line and the oldest scan line so that the addresses of these scan lines can be compared synchronously; The latest scanning line sentence is not time-delayed by inputting N consecutive output signals of the AND means 3 supplied from the delay means 4 for a total of N+1 minutes. And the AND signal P3 is not read from the output signal of the oldest scan line 18 which is time-delayed, and for the remaining N-1 scan lines, the latest scan line sentence or multiple lines including this scan line are read out. When the AND signal P3 is detected from the scanning line of The small hole address signal generating means 6 outputs a hole address signal. If the stoma address signal is to be used repeatedly, a storage means 7 is attached to the stoma address signal generating means 6.

As a result, the image sensor 2 reads and scans the plane l in a linear manner, and sequentially shifts the line position in the right angle direction. As a result, as shown in FIG. 2, when the surrounding area 8a of the small hole 8 is line-scanned, a binarized video signal pulse P1 is first generated. The AND means 3 receives the video signal pulse P and a pulse P2 generated at a time point when the brightness of the leading edge of the small hole 8 changes during line scanning, and outputs AND signals P and 3. The time delay means 4 delays the output signals of the AND means 3 of the inputted N scanning lines to be delayed so that the addresses of each scanning line are synchronized.

As a result, the small hole judgment means 5 selects the temporally first scanning line sentence that is not delayed among the N,11 scanning lines (the total number of scanning lines to be judged). and the oldest delayed scan line statement, there is no AND signal P, while for the remaining N-1 tree scan lines (number covering hole 8), l# new delayed From a scanning line sentence or multiple scanning lines including this scanning line (IL in Figure 2, only one tree, time width T equivalent to the radius in Figure 3,
When the AND signal P3 is detected, it is determined that a small hole exists and a small hole detection signal is output.

The small hole address signal generating means 6 outputs a two-dimensional small hole address signal at that time every time a small hole detection signal is generated.

(Problem 8 to be solved by the invention) With such a device, the two-dimensional address of a small hole can be automatically detected for automatic hole machining, etc., but it is possible to automatically detect the two-dimensional address of a small hole. When multiple small hole detection signals are generated for one small hole, such as when the pulse waveform corresponding to the small hole is distorted at the rising or falling point of the pulse waveform. However, there was still room to improve the reliability of operation.

Therefore, the present invention aims to improve the reliability of the operation in the above-mentioned small hole position detection device that automatically detects the two-dimensional address of a small hole surrounded by areas of different brightness on a plane. purpose.

(Means for Solving the Problems) In order to achieve this object, the present invention, as shown in FIG. 1, transmits the video signal pulses of the oldest scan line sentence to the latest scan line sentence which is not time-delayed. A video signal pulse time delay means 9a for time delaying the video signal pulse so as to be synchronously compared with the video signal pulse, and in response to the video signal pulse, corresponds to a line scanning time slightly wider than the diameter of the ostium at the leading edge of the ostium. and a prohibition pulse generating means 9b for generating a small hole detection prohibition pulse having a time width, and a small hole f1 cutting means 5.
and the small hole address signal generating means 6, when the small hole preliminary detection signal is generated, the video signal pulse P and the video signal pulse output from the pulse time delay means 9a are both present, and the small hole detection prohibition pulse is present. or when it is not output,
A small hole preliminary detection signal determining means 9 for inputting a regular small hole detection signal to the small hole address signal generating means 6 is also inserted.

[Effect]

To explain the small hole in FIG. 3, the small hole preliminary detection signal determining means 9 detects (a) the first scanning line that passes the edge of the small hole; When scanning the video signal pulse P. (b)
Since a video signal pulse is generated even when scanning the oldest scanning line sentence, the video signal pulse time delay means 9a
A synchronized delayed video signal pulse Pln is also output from
(c) Further (the latest scanning line sentence) is input to the area of time width Tr when the small hole detection prohibition pulse Pp is not generated from the prohibition pulse generating means 9b due to not scanning the small hole (dotted line 8 in the figure). The incoming small hole preliminary detection signal C is judged to be normal, and the normal small hole detection signal C is supplied to the small hole address signal generating means 6.

If for some reason a small hole preliminary detection signal is generated at a position other than the small hole that is not surrounded by the surrounding area, the scanning line statement will be sent. Or sentence, or both sentences. , sentence, video signal pulse P
Since ro and Pin do not exist, it is determined that there is an abnormality, and the normal small hole detection signal C is not output. View scan lines without time delay. If a small hole preliminary detection signal is generated when scanning a small hole or a gap, a small hole detection prohibition pulse PP is generated from the prohibition pulse generating means 9b, and it is determined that there is an abnormality.

(Embodiment of the invention) FIG. 4 shows a small hole position detection device according to an embodiment of the invention.

In the same figure, the printed circuit board film 17, where the copper foil part is black and the other parts are transparent, is imaged by the TV left camera 9, and the video signal is transmitted to the Nant gate 10 as an AND means and the monostable as a pulse generating means. Multi vibrator 11
is supplied to That is, when the black ring-shaped surrounding area 18a of the small hole 18 is line-scanned, a binarized video signal pulse a is generated, and this pulse a and the video signal pulse a are combined in the monostable multivibrator 11. A gate signal P12 generated at the falling edge and corresponding to a scanning time width slightly larger than the diameter of the small hole 18 is input to the Nant Gate)-10.

Reference numerals 21 to 24 designate shift registers that serve as time delay means for the output signal of the Nandt gate 10 and are configured in four stages because the number of scanning lines crossing the small hole 18 is three. Then, the output signal of the Nant gate 10 is supplied to the shift register 21 in the first stage, and is sequentially transferred to the shift registers 22 to 24 in the subsequent stages by a clock.

Reference numeral 28 denotes an ant gate 1 which functions as a small hole determination means, the output signals of the shift registers 21 to 23 are inverted by an inverter 25, and the output signals of the Nant gate 10 and the output signal from the shift register 24 are input as they are. As a result, the AND signal PI3 of these shift registers
The pulse width of the output signal corresponding to the shift register 21 is
A coincident time occurs when all the output signals from 23 to 23 become H level, and a small hole preliminary detection signal S at H level is output.

31 is a counter that counts the X-axis step pulses of the TV left camera 9 and is reset each time each line is scanned; 32 is a counter that counts the Y-axis step pulses and is reset each time one screen finishes scanning. be. Then, the small hole preliminary detection signal from the AND gate 28 takes in these X and Y axis count values as address signals at the time when they are input as the regular small hole detection signal C, as will be described later. Address signal output circuit 3 that outputs an address signal by correcting the expected deviation from the address of the actual center position of the small hole 18
3 constitutes a small hole address signal generating means.

39 is a memory for storing the small hole position signal on the two-dimensional plane of the X and Y axes.

Each of the parts described above substantially corresponds to the configuration according to Japanese Patent Application No. Sho. At least 4 lock operated
A monostable monostable which is triggered at the falling edge of the video signal pulse a and generates an L-level gate pulse serves as a prohibition pulse generating means for generating a small hole detection prohibition pulse P using a shift register consisting of stages 41 to 44. Multivibrator 45, H level small hole preliminary detection signal S, H level video signal pulse a, H level delayed video signal pulse P0 outputted from shift register 44, and L level from monostable multivibrator 45. When the small hole detection prohibition pulse Pp is input and all of these four input signal levels are at H level, the address signal output circuit outputs the regular small hole detection signal C corresponding to the small hole preliminary detection signal at L level. 33
A Nantes gate 46 is added as a small hole detection signal determining means to be inputted into the pore detection signal.

The operation of the small hole position detection device configured as described above is as follows.

When scanning each line on the X axis, a black ring-shaped surrounding area 18a
When is scanned, an H-level video signal pulse a is generated. At this time, the monostable multivibrator 11 generates a pulse signal PI2 at the time when the brightness changes from black to white, and during this time, when the video signal pulse a of the black surrounding area 18a is input to the Nant gate 10, the AND signal PI3 Output. The shift registers 21 to 24 sequentially hold the output signals of the four consecutive Nant gates 10, and each time the contents are sequentially transferred using the progressive clock of the X-axis in-scan, a match is made at the AND gate 28C. A judgment is made. Then, the logical product signal PI3 does not exist in the output signals of the Nant gate 10 and the shift register 24, and the logic 8! which coincides in time with all of the remaining shift registers 21 to 23! If a signal corresponding to signal P12 is present, a small hole preliminary detection signal S is output.

This small hole pre-detection signal is fed to the Nantes gate 46, which in the state shown in FIG. 5a, detects the latest scan line. , an H-level video signal pulse a corresponding to the crossing time of the surrounding region 18a is generated, and the shift register
4 and 4 are delayed video signal pulses P corresponding to the video signal pulse a of fL4 four times earlier.

is output, plus the latest scanline statement. In order not to cross the small hole 18, the monostable multivibrator 45 generates the small hole detection prohibition pulse PP at the time when the small hole preliminary detection signal S is generated.
is not generated and remains at H level, and a normal small hole detection signal C is output based on the judgment of coincidence by the Nant gate 46.

The counters 31 and 32 sequentially count up the X-axis scanning and YWII scanning clocks, and the address signal output circuit 33 corrects the count value at the time when the regular small hole detection signal C is input, and corrects the X-axis and YWII scanning clocks. A small hole address signal is output as the Y-axis address and stored in the memory 39.

Scanning edge. However, as shown in FIG. 5, when scanning the small hole 18, the monostable multivibrator 4 is activated during the scanning.
5 generates the small hole detection prohibition pulse PP of L level, and therefore the normal small hole detection signal C is not generated from the Nant gate 46. In addition, the delayed video signal pulse P from 44 is output by the shift register. If the real-time video signal pulse a does not exist, or if the real-time video signal pulse a does not occur, it means that the small hole 18 is not in a regular shape surrounded by the upper or lower periphery in the diagram. The small hole detection signal C is not generated.

In the above embodiments, a memory such as a RAM may be used instead of the shift register as the time delay means. Further, the small hole preliminary detection signal determining means may be configured to control a switch circuit into which the small hole preliminary detection signal is input.

(Effects of the Invention) According to the present invention, when a small hole is read and scanned by an image sensor and a small hole detection signal is derived from the image signal, the two-dimensional address of the small hole is automatically detected. By determining whether or not the small hole detection signal is properly generated at the small hole position, the detection accuracy is greatly improved.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the configuration of the present invention, Fig. 2 and Fig. 313
+;t A diagram explaining the operation, FIG. 4 is a diagram showing the configuration of a punching device according to an embodiment of the present invention, and FIG. 5 is an operation waveform diagram of the same embodiment. 1...Plane, 2...Image sensor, 8.1
8... Small hole, 8a, 18a... Surrounding area, 19
...TV camera.

Claims (1)

[Scope of Claims] An image sensor that reads and scans a plane in which small holes surrounded by regions of different brightness are arranged in a line, and outputs a video signal while sequentially shifting the line position in a right angle direction; A pulse that generates a pulse having a time width corresponding to a line scanning time slightly wider than the diameter of the small hole at the leading edge of the small hole in response to a video signal pulse obtained by binarizing the video signal according to a change in brightness. a generating means, an AND means which inputs this pulse and the video signal pulse, and N, the number of which each scanning line sequentially covers the small holes + 1.
a time delay means for time-delaying the output signal of the AND means for at least the newest scanning line and the oldest scanning line of the book so that the addresses of these scanning lines can be synchronously compared; By inputting an output signal that is not time-delayed and a maximum of N output signals of the AND means supplied from the time delay means, the first scan line that is not time-delayed and the oldest scan line that is time-delayed are The AND signal is not detected in the output signal, and for the remaining N-1 scan lines, the AND signal is detected from the newest scan line or a plurality of scan lines including this scan line. a small hole determining means that determines that there is a possibility that the small hole exists and outputs a small hole preliminary detection signal; and a two-dimensional small hole address signal corresponding to the detection time of the small hole preliminary detection signal. and a small hole address signal generating means for outputting a small hole address signal generating means, wherein the video signal pulse of the oldest scanning line is synchronously compared with the video signal pulse of the latest scanning line that is not delayed in time. a time delay means for a video signal pulse to time-delay the video signal pulse, and a small hole having a time width corresponding to a line scanning time slightly wider than the diameter of the small hole at the leading edge of the small hole in response to the video signal pulse; and a prohibition pulse generating means for generating a detection prohibition pulse, and between the small hole determining means and the small hole address signal generating means, when the small hole preliminary detection signal is generated, the video signal pulse and the pulse time are provided. A small hole that supplies a regular small hole detection signal to the small hole address signal generating means only when the video signal pulse output from the delay means is present and the small hole detection prohibition pulse is not output. A small hole position detection device characterized in that a preliminary detection signal determination means is inserted.