JPH0342457B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for detecting the trailing edge of photographic film pulled out from a spool.

Conventionally, when cutting the rear edge of photographic film when it is pulled out from the spool and spliced, the tension when the photographic film is completely pulled out from the spool activates a trailing edge detection switch to detect the rear edge of the photographic film. The signal from this rear end detection switch operates the rear end cutting means. However, if the photographic film has some sort of problem, the film will not unravel smoothly from the spool, and a tension will be applied that activates the trailing edge detection switch while the film is being pulled out. Although it is extremely rare, the problem of being left behind does occur.

In order to solve the above-mentioned problems, the present applicant previously proposed a photographic film trailing edge detection device (Japanese Patent Application Laid-open No. 76544/1983). The device disclosed therein detects light using an optical detector, and according to this method, for example, if a photographic film is damaged and light passes through it, it will be detected. Problems still remain, such as erroneously detecting the trailing edge of the film and cutting the film in the middle.

It is an object of the present invention to solve the problem of the photographic film wound on a spool etc. being tensioned by the tension detector while it is being pulled out and cutting the photographic film midway, or the photographic film being erroneously detected by the optical system detector. An object of the present invention is to provide a trailing edge detection device for a photographic film that more reliably eliminates troubles such as cutting in the middle of a photographic film.

The above-mentioned object of the present invention is to provide a device for detecting the trailing edge of a photographic film pulled out from a spool, including transmitted light amount detectors disposed at a plurality of positions, and a combination pattern of transmitted light amounts detected by each of the transmitted light amount detectors. is stored in advance, and the combination pattern of the amount of transmitted light actually detected by the transmitted light amount detector is compared with the combination pattern of the storage means, and when they match, it is determined that it is the rear end of the photographic film. This is achieved by a photographic film trailing edge detecting device characterized in that it is equipped with a comparing means for outputting the following.

Hereinafter, one embodiment of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 is a schematic plan view showing a state in which the photographic film is completely pulled out from the cartridge and the tension is not yet applied, and FIG. 2 is a side sectional view thereof.

In the figure, the rear end 5a of the photographic film is fixed to a spool 6 of the cartridge, and the photographic film 5 is wound along the substrate P in the direction of the arrow shown in the figure by a film winding device (not shown). has been done.

Also, in this case, the photographic film 5 is on the spool 6.
Tension detection means is provided for detecting and outputting the tension applied to the spool core 6 when the spool core 6 is pulled out and its rear end appears. This tension detection means includes a guide rod 1 extending in the horizontal direction.
Rotating lever 10 and switch 1 having 1 and 12
5. The rotating lever 10 is appropriately biased by a spring in the direction of arrow H shown in FIG. 2, using a rotating support shaft 13 as a fulcrum. The flange portion 7 of the spool 6 is supported in contact with guide rods 11 and 12 of a rotary lever 10, and when tension is applied to the photographic film 5, the rotary lever 10 is moved around the support shaft 13 as a fulcrum. When the rotary lever 10 moves in the direction F, and as a result, the rotary lever 10 rotates in the direction of the arrow G, the switch 15 is turned on to generate a tension detection signal.

1a, 2a, 3a, 4a and 1b, 2 in the diagram
b, 3b, and 4b are a group of rear end detectors of the photographic film 5, which are preferably optical type detectors, and for example, a transmitted light amount detector capable of detecting the amount of light may be used. This transmitted light amount detector is the projector 1
a, 2a, 3a, 4a and receivers 1b, 2b, 3
b and 4b, and infrared rays are used as detection light. The light projector and light receiver are a light projector 1a, a light receiver 1b, and a light projector 2, respectively.
A and a light receiver 2b, a light emitter 3a and a light receiver 3a, and a light emitter 4a and a light receiver 4b form pairs, and the light intensity can be detected at four locations in the optical paths 1, 2, 3, and 4 of the pairs, respectively. ing. The number of the transmitted light amount detectors may be plural, and as mentioned above, the number of the transmitted light amount detectors is four.
It is not limited to.

When the photographic film is under tension and the rotary lever 10 is moved in the G direction, the respective light emitters and light receivers have optical paths 1, 2, 3,
4 are arranged in the positional relationship shown in FIG. The optical path 3 between the emitter 3a and the receiver 3b is located approximately at the center of the width of the photographic film 5.
The optical path 4 of the light receiver 4b is located at an appropriate distance from the optical path 3. The optical path 1 of the emitter 1a and the receiver 1b is arranged so that it does not coincide with the travel line of the perforation 8, and so that when the rear end of the photographic film 5 is pulled out, it is located away from the film surface. The emitter 2a and the receiver 2b
The optical path 2 is also arranged so that it does not coincide with the running line of the perforation 8, and when the rear end portion is pulled out, it is at a position away from the film surface on the opposite side to the optical path 1. .

The light receivers 1b, 2b, 3b, and 4b are the light receivers 1b and 2b, assuming that the amount of light from each light emitter is constant when the photographic film 5 is completely pulled out.
b detects the same amount of received light, and light receivers 3b and 4b detect the same amount of received light. For example, let A be the amount of received light in each of the former cases, and B be the amount of received light in the latter case. A storage means that stores this combination pattern (X) of the amount of light received by each light receiver, or a register circuit 17 (see FIG. 4), stores the cutter 1 of the photographic film 5.
It is connected to the actuating thread of 4.

Further, the operating system includes light receivers 1b, 2b, 3.
A comparison circuit that compares and matches the combination pattern of the amount of received light actually detected by b, 4b and the combination pattern (X) stored in the register circuit 17, determines that it is the rear end of the photographic film 5, and outputs the result. 18
(See Figure 4).

The operation of cutting the photographic film 5 constructed as above will be explained with reference to the block diagram shown in FIG.

While the photographic film 5 is being wound up by a winding device (not shown), the light receiver 1 is normally
b, 2b, 3b, and 4b each have the same amount of light received B
is detected, and the signal of this combination pattern is input to the comparison circuit 18 via the detection circuit 16. The comparison circuit 18 compares the input combination pattern with the combination pattern (X ₁ ) stored in the register circuit 17, but does not output trailing edge detection because the combination patterns do not match. However, as shown in FIGS. 1 and 2, when the photographic film 5 is completely pulled out and tension is applied and the rotary lever 10 moves in the G direction, the photoreceptors 1b, 2b, 3b, and 4b are connected to the register circuit 17 in advance. Combination pattern stored in (X ₁ )
The signal of this combination pattern (X ₁ ) is input to the comparison circuit 18 via the detection circuit. In this case, since the signal of the input combination pattern (X) is the same as the combination pattern (X ₁ ) stored in the register circuit, the comparison circuit 18 outputs this signal and the tension detection signal from the switch 15. operates the cutter 14 via the cutter drive circuit 19 to cut a predetermined rear end of the photographic film 5.

In this way, if the photographic film is cut only when a predetermined combination pattern of detection signals from the plurality of detectors is detected, it is possible to avoid problems such as film damage or adhesion failure during film winding. Even if the switch 15 outputs a film tension detection signal, it does not output a rear edge detection signal because the predetermined combination pattern is not achieved. Therefore, there is no chance of accidentally cutting the film.

That is, if the photographic film 5 wound around the spool 6 is not unraveled smoothly and the tension is applied to the photographic film 5, the rotary lever 10 is activated and the switch 15 is turned on as described above.
This signal is input to the comparison circuit 18, but since the combination pattern of the light receivers 1b, 2b, 3b, and 4b at this time is different from the predetermined combination pattern, the comparison circuit 18 sends a signal to activate the alarm 20 to notify of trouble. Output. However, when the photographic film 5 is completely pulled out and a pattern matching a predetermined pattern stored in advance is detected, the predetermined cutting is performed without activating the alarm 20.

By using the tension detection means in combination with the combination pattern matching detection method described above, the object of the present invention can be achieved more reliably.

The present invention is not limited to the case where the shape of the rear end of the photographic film 5 fixed to the spool 6 is as shown in FIG. The method shown in can also be used.

In FIG. 5, the rear end of a photographic film 5 having a perforation 8 is connected to a leader tape 9a fixed to a spool 6 at an overlapping portion 9 shown in the figure. In this case, 4
Optical paths 1, 2, 3, and 4 are arranged so that the amount of light is detected at three points.
For example, if optical paths 1 and 2 are connected to the leader tape 9
Amount of light passing through a C, optical path 3 is leader tape 9
a, the amount of light D passing through the photographic film 5, and the light path 4 becomes a combination pattern (X ₂ ) consisting of the amount B of light passing through the photographic film 5. If this combination pattern (X ₂ ) is stored in the register circuit 17,
Even with the method shown in FIG. 5, the rear end of the photographic film 5 can be detected when the combination pattern (X ₂ ) is input, and the same effects as in the embodiment described above can be achieved.

Furthermore, if the combination patterns (X ₁ ) and (X ₂ ) of the above-mentioned two types of fixing methods to the spool are stored in the same storage means in advance, the rear ends of the two types of photographic films can be stored in the same device. Detection can be performed accurately. As mentioned above, the method of fixing the film to the spool may differ depending on the manufacturer of the photographic film, and if you memorize multiple combination patterns (X ₁ ...Xn) that suit each method, you can It is possible to reliably detect the trailing edge of the film without having to choose between the two.

The photographic film trailing edge detection device of the present invention can be applied, for example, to a photographic film splicer that sequentially splices photographic films stored in a cartridge into a long film in order to develop the photographed film. In this case, the effects of the present invention will be even more remarkable.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view of one embodiment of a photographic film trailing edge detection device according to the present invention, FIG. 2 is a schematic side sectional view of the device, and FIG. 3 is an embodiment of the apparatus shown in FIGS. 1 and 2. FIG. 4 is a plan view of the film trailing edge fixing system of the example, FIG. 4 is a block diagram of the device, and FIG. 5 is a plan view showing another film trailing edge fixing system. 1, 2, 3, 4... optical path, 1a, 2a, 3a,
4a... Emitter, 1b, 2b, 3b, 4b... Receiver, 5... Photographic film, 6... Spool, 7
...Flange part, 8...Perflation, 9
... Overlapping part, 10 ... Rotating lever, 11, 12 ...
...Guide rod, 13...Rotation shaft, 14...Cut, 15...Switch, 16...Detection circuit, 17
...Register circuit, 18...Comparison circuit, 19...
Katsuta drive circuit, 20...Alarm.

Claims (1)

[Claims] 1. A device for detecting the trailing edge of photographic film pulled out from a spool, including transmitted light amount detectors disposed at a plurality of positions, and a memory storing combination patterns of transmitted light amounts detected by each of the transmitted light amount detectors. and a comparison means for comparing and collating the combination pattern of the amount of transmitted light actually detected by the transmitted light amount detector and the combination pattern stored in the storage means and outputting it when they match. Film trailing edge detection device.