JPS6247630A - Retrieving device for microfilm - Google Patents

Abstract

PURPOSE:To prevent wrong retrieval from being performed by making mark detection ineffective when a film feed direction when a blip mark reaches the detection point of a blip mark detecting means is not coincident with a film feed direction when the blip mark exits from the detection point. CONSTITUTION:Blip marks 3a-3c of different size corresponding to frames are imprinted at one edge part of a microfilm 1 and light from a light source 5 is transmitted through the film 1 and guided a photoelectric conversion element 10 through an optical fiber 4 to detect the marks 3. The movement of the film 1 is detected by an encoder 7 coupled directly with a roller 6 is rotated following up the movement. Up/down counters 28 and 29 generate data on the widths of the marks 3a-3c. The feed directions of the film when a mark 3 reaches the detection point 4p of the fiber 4 and exits from it are stored in latch circuits 32 and 31 and an exclusive OR circuit 33 decides the dissidence between both directions to set a count data ineffective flag. Thus, wrong retrieval is prevented from being performed.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a microfilm retrieval device in a league printer or the like.

2. Description of the Related Art A device for searching for a desired frame by controlling the feeding of a microfilm having blip marks of different sizes corresponding to each frame on one edge is known, for example, from Japanese Patent Laid-Open No. 60-80824. It is being

The above publication describes a blip mark detection means that has a single detection point on the trajectory of the blip mark and detects the presence/absence of the blip mark, and a blip mark detection means that has a single detection point on the locus of the passage of the blip mark, and a means for detecting the presence or absence of a blip mark, as well as a means for detecting the presence or absence of a blip mark, and a means for detecting the presence or absence of a blip mark. pulse counting means for counting the pulses generated by the pulse generating means while the generation detection means detects the blip mark; and a size of the blip mark based on the count value of the pulse counting means. A search device is disclosed that includes a blip mark discriminating means for discriminating a blip mark.

Specifically shown in Figure 1, (1) is a series of information pieces (2
) is a microfilm with three levels of blip marks (3) consisting of block, item, and piece for each piece: large mark (3a), medium mark (3b).

A small mark (3c) is imprinted at the same time. This microfilm (1) is sent in forward and reverse directions by a driving means (not shown). An optical fiber (4) having a light detection point (4p) is arranged on the trajectory of the blip mark (3), and the light from the light source lamp (5) passes through the microfilm (1). Transparent optical fiber (4
), the signal is guided to a photoelectric conversion element (not shown in FIG. 1), and is converted into an electrical signal indicating the presence/absence of the blip mark (3).

On the other hand, (6) is a roller that is arranged to rotate forward and reverse in accordance with the forward and reverse feeding of the microfilm (1). An encoder (7) for detecting the film feed amount and film feed direction is connected to the rotation shaft of the roller (6). This encoder (7
) is a two-phase output type, which generates n pulses for each phase per rotation of the rotary shaft, and the phase of each phase output is always shifted by 174 cycles. When the microfilm (1) is being fed in the forward direction, the A-phase output is 90 degrees ahead of the B-phase output, as shown in Figure 2 (a), and the microfilm (1) is being fed in the opposite direction. Figure 2 (
As shown in b), the phase of the A-phase output is delayed by 90 degrees from the B-phase output. The amount of film feed is detected by combining these A-phase pulses and B-phase pulses (for example, by taking exclusive OR) and multiplying them to make 2n or 4n pulses per rotation of the rotating shaft and counting them. Ru. In addition, in the film feeding direction, the B phase output basically changes from logic level "L" to "
It can be detected by whether the logic level of the A phase output is "H" or "L" when it changes to "H".For example, if it is "H", the film will be fed in the forward direction, and if it is "L", it will be detected. It is predefined that the feed is in the reverse direction.

The above three detection signals, namely, the blip mark detection signal from the photoelectric conversion element, the film feed amount signal, and the film feed direction signal are used to determine whether the blip mark (3) is large, medium, or small.

Specifically, for example, during the period when the photoelectric conversion element is detecting the blip mark (3), an up-down counter counts film feed pulses in the plus direction and minus direction according to the film feed direction, and calculates the blip.
When the mark (3) finishes passing, the dust on the film, the small mark (3c), the medium mark (3b), and the large mark (3a) can be determined based on the count of this up/down counter. Is going.

However, as shown in Figure 3, a large mark (3a) or a medium mark (3b) appears at the detection point (4p), and the mark is detected in the same feeding direction. No extraction is made from point (4p), and a count value of about several counts may remain in the up/down counter, that is, the counter for counting the blip mark width. Theoretically, the count value would be zero because it would count up in the forward direction and down by the same feed amount in the reverse direction, but the spatial mechanical system and the electricity that replaces space with the time axis There are fundamentally large differences in precision in control systems, and theories cannot be directly applied. For example, because the roller (6) cannot completely follow the film advance, the reversal operation of the signal system is delayed from the reversal of the film, and the signal in the film advance direction is based on the two-phase output of the encoder (7). The reason for this is that the signal system cannot be inverted until this output is inverted.

When the number remaining in the blip mark width counter is about the lower limit value for determining a small mark (3c), it may be determined that this is a small mark.
Counting the number of pieces should not be done 1/7'l Kranji W
Haroku Uso Ll Yujiman Engu ji 1 ± -nlan n 1
It has been pointed out that this may cause erroneous searches. Of course, if you use an extremely expensive high-precision encoder that generates a large number of pulses per rotation of the rotating shaft (for example, 400 pulses), it would be possible to sufficiently discriminate between the remaining count value and the count value related to the small mark. , the number of generated pulses is small (for example, 1
When using an encoder (with 00 pulses), there were many problems in that it was not possible to distinguish between the two.

The present invention prevents this type of error from being mistakenly determined as a count value related to a small mark even if an encoder that generates a small number of pulses per revolution, that is, an inexpensive encoder, is used. The purpose is to prevent searches.

. In order to solve the above problems, the present invention searches for a desired frame by controlling the feeding of a microfilm having blip marks of different sizes corresponding to each frame on one edge. The blip mark is a device that has a single detection point on the trajectory of the blip mark and detects the presence/absence of a blip mark.
a mark detection means, a pulse generation means for generating a number of pulses corresponding to the amount of microfilm feeding, and a pulse generated by the pulse generation means when the blip mark detection means detects a blip mark. and a blip mark discriminating means for discriminating the size of the blip mark based on the count value of the pulse counting means.
A film feeding direction determining means for determining whether the film feeding direction matches/mismatches when a blip mark enters a detection point of a mark detecting means and when the blip mark comes out from this detection point, and this determining means The basic feature is that the mark detection disabling means for prohibiting the operation of the blip/mark discriminating means when it is determined that the blip/mark discriminating means does not match.

Inukaki A Hereinafter, the present invention will be specifically explained based on Examples.

FIG. 4 shows a circuit diagram of one embodiment, and FIG. 5 shows a timing diagram of the circuit. '# In figure S4,
(10) is the charging conversion element described in Fig. 1, which generates an electric signal according to the amount of input light, and this electric signal is passed through the inverting amplifier (11) and the next stage voltage comparator (12). , is formed into a mark detection signal (Ql) which gives a logic level 'H' at the blip mark and a logic level 'L' at the film base.The signal (Ql) is processed by an inverting circuit (13
) and input to the one-shot multivibrator (14). When the multi-by-break (14) receives a rising signal from "L" to "H" to its tri-input, it generates a pulse of positive polarity and sends it to the microcomputer (15) as an interrupt signal (Q2). This multivibrator (14) outputs the completion of passing the blip mark to the micro combinator (14).
5) and cause the microcomputer (15) to process the mark! It provides the flIJ signal.

On the other hand, (7) is! The encoder in Figure @1 outputs the A-phase pulse signal (Q3) and the B-phase pulse signal (Q4). The exclusive off circuit (16) receives the signal (Q3
).

(Q4) to create a signal (Q5) with twice the frequency.

Further, the exclusive off circuit (17) receives the signal (
q5) and a signal (q5) inverted by the inverting circuit (18), or a signal (q6) with twice the frequency of the muttering signal (Q5).
Create. The signal (Q6) is used as a pulse signal to detect the amount of film feed, and is sent to a two-man AND circuit (1
8) and (19).

The data latch circuit (20) receives a signal (
Q3), the bird uses the input as a signal (Q6) and outputs a signal (Ql) related to the film feeding direction. The data latch circuit (21) also receives a signal (Q4) as a data input.
The bird takes the input as the signal (Q6') and outputs the signal (Q8). The signal (Q6') is generated by inverting the signal (q6) with two inverting circuits (22).

(23) and is a signal obtained by adding a time delay to this signal (Q6). The data latch circuit (24) is
The above signal (Q8) is used as the data input, and the input is the signal (
The data latch circuits (20), (21), (24) and other data latch circuits in FIG. The exclusive off circuit (25) receives a signal (Ql) and a signal (Q8'
) are input, the exclusive OR is taken, and a film advance direction signal (Q9) is output. When the film is being fed in the forward direction, the signal (Q9) is at the "H" level, and when the film is being fed in the reverse direction, the signal (Q9) is at the "L" level. The circuit configuration described above for generating the film feed amount pulse signal and the film feed direction signal from the two-phase output of the encoder is well known, and a more detailed explanation will be omitted.

The film feed direction signal (Q9) is input to the other input of the AND circuit (18), and is input to the other input of another AND circuit (19) via the inverting circuit (26). In addition, the signal (Q9) is connected to the microcomputer (15
) is input into a predetermined input boat. The signal input to this input port determines the film advance direction flag rlJJOJ defined in the program in the microcomputer (15). The AND circuit (18) passes the film feed amount pulse signal (Q6) when the film is being fed in the forward direction, and outputs it to the AND circuit (27). The mark detection signal (Ql) is input to the other input of the AND circuit (27).
) allows the pulse signal (Q6) to pass only when the signal (Ql) is "g", that is, when a blip mark is being detected;
It is output as a signal (QIO) to the up input of the 4-bit amplifier down counter (29). On the other hand, the AND circuit (19) passes the film feed amount pulse signal (Q6) when the film is being fed in the reverse direction, and outputs it to the AND circuit (28). The mark detection signal (Ql) is input to the other input of the AND circuit (28), and this AND circuit (28) allows the pulse signal (Q6) to pass only when the signal (Ql) is "H". , is output as a signal (Qll) to the down input of the up/down counter (29).

The up/down counter (30) is the same 4-bit one as the 7/p down counter (29), and its up input is connected to the carry output of the counter (29).
The borrow output of the counter (29) is connected to the down input. In these two up/down counters, data related to the width of large, medium, and small blip marks (
This count data is input to the microcomputer (15) via a predetermined input port of the microcomputer (15). The clear inputs of each of the counters (29) and (30) are connected to a predetermined output port of the microcomputer (15), and these counters are simultaneously cleared by a signal from the microcomputer (15).

On the other hand, the data latch circuits (31) and (32) have the film feed direction signal (Q9) input to their respective data inputs, and the input of the data latch circuit (31) is the input of the inverting circuit (13). The output of the other data latch circuit (32) is input with the mark detection signal (Q
l) has been input. The data latch circuit (32) is
The film feeding direction at the moment when the mark detection signal rises, that is, the blip mark (3) enters the detection point (4p) shown in FIGS. 1 and 3, is memorized. On the other hand, the data latch circuit (31) stores the film feeding direction at the falling edge of the mark detection signal, that is, at the moment when the blip mark (3) is removed from the detection point (4p). Data latch circuits (32), (31) output signals (Ql3), (012
) is input to a two-man exclusive off circuit (33), which outputs its output signal (Ql4) to a predetermined input port of the microcomputer (15). The signal input to this input port determines "1" or "0" of the "count data invalid flag" defined in the program in the microcomputer (15). That is, if the signal (Ql2) and the signal (013) are both H" or both L, the circuit (33) outputs the "L" level signal (Ql4) as a matching signal; otherwise, If the film feed direction when the blip mark enters the detection point (4p) is different from the film feed direction when the blip mark comes out, it is determined that there is a discrepancy, and the signal (Ql4) at the “■～■” level is counted as data. Output as invalid flag.

In the timing diagram of FIG.
, as you can see from the signal (Qll), when feeding in the forward direction, 4
On the other hand, in the opposite direction, the count is 3, and the mark width counting counters (29) and (30) are left with 1 count of the subtracted square. FIG. 5 is a timing waveform shown for explanation; in reality, a larger number of counts remains due to slippage between the film and the roller (6), etc.

Now, if the blip mark passes through the detection point at the time point (0) in FIG. 5, the circuit (14) in FIG.
2) and outputs the pulse signal of microcomputer (1).
5) requests an interrupt. Microcomputer (15
) accepts the interrupt, count data has already been formed in the mark width counting counters (29) and (30), and the film feed direction flag and The count data invalid flag is also determined by the signal (Q14).

When an interrupt request is received, the microcomputer (15) temporarily suspends the process currently being executed and starts the interrupt process (
(interrupt routine) is executed. The contents are shown in chart 70 of FIG.

In FIG. 6, first, in step (Sl), the contents of various registers built into the microphone computer are saved. Next, in step (S2), it is determined whether the count data invalid flag is ON, that is, "1".

If it is determined that it is not "1", the normal processing from step (S3) to step (Sho) is performed, that is, the film feed direction flag is determined, and the count data related to the mark width is read according to the determination result. Each process is performed by determining the size of the mark based on the count value.

On the other hand, if it is determined in step (S2) that the count data invalid flag is ON, that is, "1",
This is a case where the film feeding direction is different at the beginning and end of mark detection, so steps (S3) to (3)
Step 18) is not performed and the process immediately proceeds to step (S19). Here, a signal is output to clear the mark width counters (29) and (30) in preparation for the next mark detection.

In step (S20), the contents of the register saved in step (Sl) are restored to the register, the loading process is completed, and the routine returns to the main routine to which this routine belongs. Upon return, the microcomputer resumes the process that was interrupted earlier.

Note that in the above embodiment, the blip mark detection point (4
p) is the tip of the optical fiber (4), but the detection point can also be the light entrance window of the optical sensor itself without using a light guiding means such as an optical fiber.

As is clear from the above explanation, according to the present invention, the count value remaining in the blip mark width counter can be mistakenly recognized as the count value related to a small mark without using a high-precision encoder. Since there is no problem, erroneous searches can be prevented and the device can be configured at low cost.

[Brief explanation of drawings]

FIG. 1 is an illustrative diagram of the main parts of a microfilm retrieval device that forms the background of the present invention, and FIGS. Figure 3 is an explanatory diagram showing how a mark enters the detection point and is sent in the opposite direction without being removed, Figure 4 is a circuit diagram according to an embodiment of the present invention, and Figure 5 is its illustration. A timing diagram of the circuit, FIG. 6 is a chart 7a showing the interrupt processing executed by the microcomputer. 1... Microfilm, 2... mYH piece, 3 a
, 3 b. 3c... Blip mark, 4p... Detection point, 7.
... Encog, 10... Photoelectric conversion element, 29.30
. . . Up/down counter, 31. 32 . . 7979 circuit, 33 . . . Exclusive OR circuit, 15 . . . Microcomputer.

Claims (1)

[Claims] (1) A device that searches for a desired frame by controlling the feeding of a microfilm that has blip marks of different sizes corresponding to each frame on one edge. Blip mark detection means has a detection point and detects the presence/absence of a blip mark; pulse generation means generates a number of pulses corresponding to the feed amount of the microfilm; and the blip mark detection means detects the presence or absence of a blip mark. pulse counting means for counting the pulses generated by the pulse generating means while detecting the mark; and blip mark discriminating means for determining the size of the blip mark based on the count value of the pulse counting means. A film feed direction determination method for determining whether the film feed direction matches or mismatches when a blip mark enters the detection point of the blip mark detection means and when the blip mark leaves the detection point. A microfilm retrieval device characterized by comprising: a mark detection disabling means for prohibiting the operation of the blip/mark discriminating means when the discriminating means determines that there is a mismatch.