JPH0950071A - Film feeding device for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To feed a film by precisely detecting a perforation. SOLUTION: This device is provided with photosensors 4 and 5 installed at the perforation passing position of the film and set for outputting the signal of a level corresponding to received light quantity, a perforation detection means 1 comparing the signals outputted from the sensors 4 and 5 with a threshold value and detecting the perforation of the film and film feeding means 3 and M feeding the film based on the detected result of the perforation by the perforation detection means 1. Besides, it is provided with a leading edge detection means 1 detecting the leading edge of the film by comparing the signals outputted from the sensors 4 and 5 with a previously set temporary threshold value when the film is fed out from a cartridge by the feeding means 3 and M and a threshold value set means 1 setting the threshold value based on the signals outputted from the sensors 4 and 5 before and after the leading edge is detected by the leading edge detection means 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film feeding device for a camera.

[0002]

2. Description of the Related Art There is known a film feeding device for a camera which feeds a film while detecting a perforation of the film by a photo sensor. In this type of feeding device, a perforation installed from the leading edge of the film is detected by a photo sensor, and the feeding control of the film is performed based on the detection result. A transmissive photo interrupter is often used as a photo sensor. Also,
The threshold value for determining whether the perforation is based on the output signal level of the photosensor, an average value of the maximum value and the minimum value of the output signal of the photosensor is set, or a fixed value is set in advance, or The fixed reference voltage of the comparator built into the photo sensor is set.

[0003]

However, in the conventional film feeding device for a camera, the output of the photosensor is set in order to set a threshold value for the perforations provided at a short interval at the leading end portion of the film. Since the A / D conversion is frequently performed to calculate the average value of the maximum value and the minimum value, there is a problem that the threshold setting process is heavily burdened.
Further, in a film feeding device that uses a preset fixed value as a threshold value, there is a problem that it is difficult to detect perforation for films having extremely different reflectances.

It is an object of the present invention to provide a film feeding device for a camera which feeds a film by accurately detecting perforations.

[0005]

[Means for Solving the Problems]

(1) In order to achieve the above object, the invention of claim 1 provides a photosensor which is installed at a perforation passage position of a film and which outputs a signal of a level according to an amount of received light, and an output signal of the photosensor. A film feeding device for a camera, comprising: a perforation detecting means for detecting the perforation of the film in comparison with a threshold value; and a film feeding means for feeding the film based on the perforation detection result by the perforation detecting means. Then, when the film is fed from the cartridge by the film feeding means, a leading edge detecting means for detecting the leading edge of the film by comparing the output signal of the photo sensor with a preset temporary threshold value, The photo sensor before and after tip detection by the tip detection means Threshold value setting means for setting the threshold value based on the output signal of. The output signal of the photo sensor before detecting the leading edge of the film by comparing the output signal of the photo sensor with the temporary threshold value and the output signal of the photo sensor after detecting the leading edge of the film Set the threshold for perforation detection based on and. Then, the output signal of the photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. (2) The invention of claim 2 is a photo sensor which is installed at a perforation passage position of a film and which outputs a signal of a level according to the amount of received light, and compares the output signal of the photo sensor with a threshold value, and the film. Film perforation detecting means for detecting the perforation of the film, and film feeding means for feeding the film on the basis of the perforation detection result by the perforation detection means. When the film is delivered from the cartridge by means of a leading edge detecting means for detecting the leading edge of the film by comparing the output signal of the photo sensor with a preset temporary threshold value, and the leading edge detecting means The output signal of the photo sensor before the tip is detected, Threshold value setting means for setting the threshold value based on the output signal of the photo sensor after a predetermined time has elapsed after the leading edge of the recording film was detected.
The output signal of the photo sensor is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of the photo sensor before the leading edge of the film and the photo after a predetermined time has elapsed after the leading edge of the film was detected. A threshold for perforation detection is set based on the output signal of the sensor. Then, the output signal of the photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. (3) The invention of claim 3 is installed before and after the perforation passage position of the film in the film feeding direction,
A plurality of photosensors that output a signal of a level according to the amount of received light, a perforation detection unit that compares the output signal of each photosensor with a threshold value to detect the perforation of the film, and a perforation by the perforation detection unit. A film feeding device of a camera comprising a film feeding means for feeding the film based on a detection result, wherein when the film is fed from a cartridge by the film feeding means, The leading edge detecting means for detecting the leading edge of the film by comparing the output signal of the photo sensor disposed on the winding spool side of the camera with a preset temporary threshold value, and the leading edge detecting means by the leading edge detecting means. Based on the output signal of each photo sensor before and after the tip detection And a threshold setting means for setting a threshold value. The output signal of the photo sensor located closest to the take-up spool side of the camera is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of each photo sensor before detecting the leading edge of the film and the film A threshold for perforation detection is set based on the output signal of each photo sensor after detecting the tip. And
The output signal of each photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. (4) The invention of claim 4 is installed before and after the perforation passage position of the film in the film feeding direction,
A plurality of photosensors that output a signal of a level according to the amount of received light, a perforation detection unit that compares the output signal of each photosensor with a threshold value to detect the perforation of the film, and a perforation by the perforation detection unit. A film feeding device of a camera comprising a film feeding means for feeding the film based on a detection result, wherein when the film is fed from a cartridge by the film feeding means, A leading edge detection unit that detects the leading edge of the film by comparing the output signal of the photo sensor disposed closest to the cartridge side with a preset temporary threshold value; and the leading edge of the film by the leading edge detection unit. Output signal of each photo sensor before And a threshold setting means for setting the threshold based from the tip of Lum is detected and the output signal of the photo sensor after a predetermined time. The output signal of the photo sensor located closest to the cartridge is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of each photo sensor before detecting the leading edge of the film and the leading edge of the film are detected. A threshold for perforation detection is set based on the output signal of each photosensor after a predetermined time has passed. Then, the output signal of each photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. According to a fifth aspect of the present invention, there is provided a first photosensor which is installed on the winding spool side of the camera in the film feeding direction at the film perforation passage position and which outputs a signal of a level according to the amount of received light. A second photo sensor, which is installed on the cartridge side in the film feeding direction at the perforation passage position of the film and outputs a signal of a level according to the amount of received light, and the output signal of each photo sensor are compared with a threshold value. A film feeding device for a camera comprising a perforation detecting means for detecting the perforation of the film, and a film feeding means for feeding the film based on the perforation detection result by the perforation detecting means,
Leading edge detection means for detecting the leading edge of the film by comparing the output signal of the first photo sensor with a preset temporary threshold value when the film is fed from the cartridge by the film feeding means, An output signal of the second photosensor before the film is fed from the cartridge by the film feeding means,
Second threshold value setting means for setting a threshold value of the second photosensor based on an output signal of the second photosensor at the time when the leading edge of the film is detected by the leading edge detecting means. Detecting the perforation using the output signal of the first photosensor before the film is fed out of the cartridge by the film feeding means and the threshold value set by the second threshold value setting means. A first threshold value setting means for setting a threshold value of the first photosensor based on the output signal of the first photosensor at the time when the perforation is detected by the means. The output signal of the first photo sensor arranged on the winding spool side of the camera is compared with a temporary threshold value to detect the leading edge of the film, and the film of the second photo sensor arranged on the cartridge side is set to the cartridge. The threshold value of the second photo sensor is set based on the output signal before being sent from the second photo sensor and the output signal of the second photo sensor when the leading edge of the film is detected by the first photo sensor. In addition, the first photosensor based on the output signal of the first photosensor before the film is sent out from the cartridge and the output signal of the first photosensor at the time when the perforation of the film is detected by the second photosensor. Set the threshold of the photo sensor. Then, the output signal of each photosensor is compared with each threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. (6) The photo sensor of the film feeding device for a camera according to claim 6 is a reflection type photo interrupter or a photo reflector. (7) The photo sensor of the film feeding device for a camera according to claim 7 is a transmissive photo interrupter or a photo reflector. (8) The perforation detection means and the leading edge detection means of the film feeding device for a camera according to claim 8 have a comparator, and the temporary threshold value and a reference voltage corresponding to the threshold value are applied to the comparator. To do.
Apply a temporary threshold voltage and a reference voltage corresponding to the threshold value to the comparator and compare with the output signal of the photo sensor,
Detect film edge and perforation. (9) The perforation detecting means and the leading edge detecting means of the film feeding device of the camera according to claim 9 are:
An A / D converter for A / D converting the output signal of the photosensor, and a microcomputer for comparing the output signal of the A / D converter with the temporary threshold value and the threshold value. A / D output signal of photo sensor
Convert and detect the film tip and perforations compared to a temporary threshold and threshold. (10) The film feeding device for a camera according to claim 10,
The output of the photosensor before the leading edge of the film is detected by the leading edge detecting means is detected by the threshold value setting means before the film is fed out of the cartridge by the film feeding means. (11) The film feeding device for a camera according to claim 11,
The temporary threshold value is commonly set for the plurality of photosensors. (12) The film feeding device for a camera according to claim 12,
If the difference between the threshold values set for the photosensors is equal to or larger than a predetermined value, it is determined that the threshold value is set abnormally. (13) The film feeding device for a camera according to claim 13 is
When the threshold value is set abnormally, the film is rewound into the cartridge, and then the film is fed again to set the threshold value.

[0006]

FIG. 1 is a block diagram showing the configuration of one embodiment. The microcomputer 1 is a one-chip type microcomputer having an A / D conversion function, a D / A conversion function, a calculation function, a comparison function, etc., and performs calculations for a photometry device, a distance measurement device, a flash device, a focus adjustment device, etc. And control. A storage device 2, a film feeding motor control device 3, a first photo sensor 4, a second photo sensor 5, a timer 6, a photometric device 7, a distance measuring device 8, a flash device 9 and the like are connected to the microcomputer 1. . The storage device 2 stores a temporary threshold value for detecting the leading edge of the film and control data. Further, a reflection type photo interrupter, a photo reflector, a transmission type photo interrupter, a photo transistor or the like can be used for the photo sensors 4 and 5, and an analog voltage corresponding to the amount of light incident on the detection position is output. These photosensors 4 and 5 are respectively connected to the A / D conversion port of the microcomputer 1, and the analog voltage is converted into a digital voltage.

The film cartridge used in this embodiment will be described below. At present, a film cartridge that is generally widely used is in a so-called tongue-out state in which the leader portion of the film is out of the cartridge when no image is taken. In place of such a tongue out film cartridge, there is proposed a film cartridge in which no tongue out, that is, a film cartridge in which the film is completely contained in the cartridge (for example, see Japanese Patent Laid-Open No. 5-313234). This type of drop-in-loading type film cartridge that does not produce a tongue has the following features as compared to the film cartridge that presently presents a tongue. (1) When handling the cartridge as a single unit, the film is always completely contained in the cartridge, and the tongue does not come out. (2) A data disk is provided for displaying information such as IS0 sensitivity and the number of frames and information such as unexposed film, partially exposed, exposed, undeveloped, and developed. (3) Information other than images related to shooting such as shooting date and time, screen size such as panorama, shooting conditions, and the like can be magnetically recorded on the film. (4) The number and position of perforations are defined for the shooting frame.

The data disk is formed integrally with the film spool in the film cartridge, and when the spool rotates as the film is fed, the data disk also rotates. Information relating to the film such as ISO sensitivity and the number of frames is recorded on the data disk as a bar code, and the information is read by the sensor from the rotating data disk. Further, the stop position of the data disk can be adjusted according to the use state of the film, and the use state of the film such as unexposed, exposed, halfway exposed can be displayed. In addition, the halfway exposure means taking out the film from the camera while leaving the unexposed frame in the middle of shooting.

FIG. 2 shows the leader portion of the film sent out from the tongue-less film cartridge. In this film, two perforations are formed at the front end and the rear end of each photographic screen on one side of the film, and their positional relationship is defined. An extra perforation is formed on the leader side of the perforation at the front end of the first shooting frame B1. Further, a cutout is formed in the leader portion of the film. Perforations on the film are detected by the photo sensor,
The film is fed based on the perforation detection result. This film is coated with a magnetic recording medium, and shooting information for each frame can be magnetically recorded via a magnetic head. During the winding of one frame after the shooting operation, a write signal is output from the magnetic head at a predetermined cycle, and shooting information is written at a predetermined recording density.

Although not shown in FIG. 2, the winding spool of the camera is on the left side of the figure, and the cartridge is on the right side. The first photo sensor 4 is arranged on the winding spool side of the camera in the film feeding direction, and the second photo sensor 5 is arranged on the cartridge side in the film feeding direction.
When the film is fed from right to left in the figure, as shown in FIG. 3, first, the second photo sensor 5 detects the leading edge of the film and the output signal changes to Lo level (a), and then, The first photo sensor 6 detects the leading edge of the film and the output signal thereof changes to the Lo level (b). When the film is further fed, the second photo sensor 5 detects two perforations at the front end of the first frame B1 and outputs two pulse signals (c to d, e to f), and then the first photo sensor. 4 detects two perforations at the front end of the first frame B1 and outputs two pulse signals (g to h, k to
m). The Lo level is set when the photosensors 4 and 5 detect the film because the detection position is blocked by the film and the incident light amount is reduced.

FIG. 4 is a flow chart showing the film feeding control. The operation of one embodiment will be described with reference to this flowchart. When the cartridge chamber (lid of the film cartridge chamber) is closed, the microcomputer 1 starts the film feeding control (S1) and confirms the presence or absence of the film cartridge (S2). The presence / absence of the film cartridge is determined by whether or not the sensor can read information about the film such as ISO sensitivity and total number of frames from the data disk of the cartridge. A cartridge loading detection switch may be installed in the cartridge chamber to detect the presence or absence of the cartridge, or the presence or absence of the cartridge may be detected depending on whether or not the DX code can be read by the DX code reading sensor. Of course, when the cartridge is not loaded, the feeding control is not performed, and the process ends. When the film cartridge is loaded, the output voltage of the first photo sensor 4 and the second photo sensor 5 is A / D converted before the film feeding motor M starts feeding the film from the cartridge, and the detection position is detected. Data is collected in the state where there is no film in (S3).

When the data collection with no film at the detection position is completed, the first threshold value for detecting the leading edge of the film, which is stored in the storage device 2, is read out and the output voltage of each photosensor 4, 5 is set. Settings are made to compare and determine the presence or absence of a film (S4). At this time, a different first threshold value may be set for each photo sensor, or a common threshold value may be set for both photo sensors. In the latter case, the storage capacity of the storage device 2 can be reduced. Further, the first threshold value may be an adjustment value at the time of manufacture or a fixed value. After setting the threshold value for detecting the leading edge of the film, the film feeding motor control device 3 is controlled to drive the feeding motor M to feed the film from the cartridge (hereinafter, this operation is referred to as thrust). Start (S5).

As the film is fed from the cartridge, the leading edge of the film first passes the detection position of the second photo sensor 5. The second as the film leading edge passes
The output voltage of the photosensor 5 changes to the Lo level as shown in FIG. 3 (point a) (S6). The output voltage of the second photosensor 5 is compared with the first threshold value, and if the output voltage of the second photosensor 5 is smaller than the first threshold value, it means that the film exists at the detection position of the second photosensor 5. Judgment is made, and the output voltage of the second photo sensor 5 is A / D converted to collect data in the state where the film is present (S7). If you continue feeding the film, the leading edge of the film will
After passing through the detection position of the photo sensor 4, the output voltage of the first photo sensor 4 changes to the Lo level as shown in FIG. 3 (point b) (S8). The output voltage of the first photo sensor 4 is compared with a first threshold value, and if the output voltage of the first photo sensor 4 is smaller than the first threshold value, the first photo sensor 4
It is determined that the film exists at the detection position of, and the output voltage of the first photosensor 4 is A / D converted to collect data in the state where the film exists (S9).

First photosensor 4 and second photosensor 5
After collecting the data in the state without film and the data in the state with film, the second threshold value for perforation detection is calculated for each photosensor, and the threshold value is set for each photosensor (S10). These second threshold values are stored in the storage device 2 or the RAM of the microcomputer 1. Here, a method of calculating the threshold value will be described. Assuming that the A / D-converted data without film is V0 and the data with film is V1, the second threshold value VTH is the average value of the two,

## EQU1 ## VTH = (V0 + V1) / 2. Alternatively,

## EQU00002 ## VTH = MIN {(2 * V0), (0.7 * V1)} where MIN represents whichever is smaller. And The threshold value may be determined by another calculation method.

When the second threshold value of each photosensor 4, 5 is set, monitoring of the output voltage of each photosensor 4, 5 is started with reference to the set second threshold value, and the second threshold value is set. The counting of perforation edges is started to feed one frame to a predetermined photographing position (S1
1). When the output voltage of each photo sensor 4, 5 changes beyond the second threshold value, it is determined that the perforation edge has passed the detection position of the photo sensor 4, 5 and the number of edges is counted. When the perforation edge is detected a predetermined number of times (four times in this embodiment) at the detection position of the first photo sensor 4 (S12), the first frame B1 is detected.
When it is determined that has reached the photographing position, the feeding motor M is stopped (S13). In this embodiment, an example of comparing the output voltage of each photosensor with a threshold value by a microcomputer to determine the presence or absence of a film, that is, the presence or absence of perforation is shown. You may make it compare an output voltage and a reference voltage and take in the comparison result in a microcomputer. In this case, the reference voltage of the comparator is set from the microcomputer via the D / A converter.

-Modification of Embodiment- FIGS. 5 and 6 are flowcharts showing a modification of the film feeding control. It should be noted that the same step numbers are assigned to the steps that perform the same processing as in the flowchart shown in FIG. 4, and the differences will be mainly described. The process until the second photo sensor 5 detects the leading edge of the film (S1 to S6) is the same as in FIG. In this modified example, when the second photo sensor 5 detects the leading edge of the film, the timer 6 starts time measurement (S6A), and when the time measured by the timer 6 exceeds a predetermined time (S6B), the output of the second photo sensor 5 is output. The voltage is A / D converted and the data with film is collected. The predetermined time of the timer 6 is set such that the film feeding speed is set so that the portion between the leading edge of the film and the first perforation, which avoids the notch at the leading edge, faces the detection position of the second photo sensor 5. Decide in consideration. As a result, it is possible to prevent data from being collected in a state where the leading end portion or the cutout portion having a peculiar shape faces the detection position of the second photosensor 5, and it is possible to collect correct data in the presence state of the film. Similarly, when the first photo sensor 4 detects the leading edge of the film, the timer 6 starts time measurement (S8A), and when the time measured by the timer 6 has passed a predetermined time (S8B), the output voltage of the first photo sensor 4 is changed. A / D conversion is performed and data with film is collected (S9). The predetermined time of the timer 6 may be the same as the predetermined time set for the second photo sensor 5 or may be different. The setting method may be the same as the setting method for the second photo sensor 5 described above. Thereafter, the second threshold value of each of the photosensors 4 and 5 is set based on the collected data similarly to the above-described embodiment, and the film is fed until the first frame B1 reaches the photographing position.

-Other Modifications- FIG. 7 is a flowchart showing another modification of the film feeding control. It should be noted that the same step numbers are assigned to the steps that perform the same processing as in the flowchart shown in FIG. 4, and the differences will be mainly described. The process until the second photo sensor 5 detects the leading edge of the film (S1 to S6) is the same as in FIG. In this modification, the second photo sensor 5
After the leading edge of the film is detected in step S6, it is subsequently determined whether or not the leading edge of the film is detected by the first photo sensor 4 (S6C). When the first photo sensor 4 detects the front end after the second photo sensor 5 detects the front end, the output voltages of the first photo sensor 4 and the second photo sensor 6 are respectively A /
The data with film is collected by D conversion, and the second threshold value of each photosensor 4, 5 is calculated as described above (S
6D). After that, as in the above-described embodiment, the first piece B1
The film is fed until reaches the shooting position. Since the second photo sensor 5 is arranged closer to the cartridge side in the film feeding direction than the first photo sensor 4, it is located at the detection position of the second photo sensor 5 when the first photo sensor 4 detects the leading edge of the film. There is always a film. Therefore, both photosensors 4 and 5 can reliably collect data with film.

-Other Modifications- FIG. 8 is a flowchart showing another modification of the film feeding control. It should be noted that the same step numbers are assigned to the steps that perform the same processing as in the flowchart shown in FIG. 4, and the differences will be mainly described. The process until the second photo sensor 5 detects the leading edge of the film (S1 to S6) is the same as in FIG. In this modification, the second photo sensor 5
When the leading edge of the film is detected by, the timer 6 starts timing (S6E). Next, when the leading edge of the film is detected by the first photo sensor 4 (S8), it is determined whether the time measured by the timer 6 has passed a predetermined time (S8).
C). When a predetermined time has elapsed, the output voltages of the photosensors 4 and 5 are A / D converted to collect data with film, and the second threshold value is calculated as described above (S8).
D). After that, the film is fed until the first frame B1 reaches the photographing position as in the above-described embodiment. When a predetermined time has passed since the leading edge of the film passed the detection position of the second photo sensor 5 and the leading edge of the film passed the detection position of the first photo sensor 4, the detection positions of both photo sensors 4 and 5 were changed. Since a film exists, collects data with a film.

-Other Modifications- FIGS. 9 and 10 are flowcharts showing another modification of the film feeding control. It should be noted that the same step numbers are assigned to the steps that perform the same processing as in the flowchart shown in FIG. 4, and the differences will be mainly described. The process until the second photo sensor 5 detects the leading edge of the film (S1 to S6) is the same as in FIG. In this modification, after the front end of the film is detected by the second photo sensor 5, the process waits until the first photo sensor 4 detects the front end of the film (S6F). When the first photo sensor 4 detects the leading edge of the film, the output voltage of the second photo sensor 5 is changed to A
/ D conversion is performed, and the film presence data of the second photo sensor 5 is collected (S6G). Based on the collected data without film and with film of the second photo sensor 5,
As described above, the second threshold value of the second photo sensor 5 is calculated and set (S6H). Next, the second photo sensor 5
When the perforation is detected in (S6I), the output voltage of the first photosensor 4 is A / D converted, and the film presence data of the first photosensor 4 is collected (S6J). The second threshold value of the first photosensor 4 is calculated and set as described above based on the collected data without film and data with film of the first photosensor 4 (S6).
K). After that, the film is fed until the first frame B1 reaches the photographing position as in the above-described embodiment.

When the first photo sensor 4 detects the leading edge of the film, a position equal to the distance between the leading edge of the film and the photo sensor faces the detection position of the second photo sensor 5, and the leading edge of the film is Even if it has a peculiar shape, it is possible to surely collect the data of a certain state of the film without collecting such data of the leading end portion by the second photosensor 5. Then, based on the accurate data with film and data without film of the second photo sensor 5,
The second threshold value of the photo sensor 5 is calculated, and the second photo sensor detects the perforation based on the second threshold value. At the time when the second photo sensor 5 detects the perforation, the leading end portion of the film has passed the detection position of the first photo sensor 4. Even if the leading end of the film has a unique shape, the first photo sensor 4 does not Data of a certain state of the film can be surely collected without collecting the data of the part. Then, the second threshold value of the second photo sensor 5 is calculated based on the accurate data with film and the data without film of the second photo sensor 5, and the second photo sensor is based on this second threshold value. To detect perforations.

FIG. 11 shows a circuit of the photosensors 4 and 5. In the circuit shown in (a), the output voltage of the photosensors 4 and 5 is sent to the A / D conversion port of the microcomputer 1, and the microcomputer 1 calculates the second threshold value to detect the leading edge of the film and the perforation. To do. Further, in the circuit shown in (b), the output voltage of the photosensors 4 and 5 is sent to a comparator and compared with a reference voltage set by the microcomputer 1 to detect the leading edge of the film and perforation. In this case, the second threshold value is calculated by directly fetching the output voltage of the photosensors 4 and 5 from the A / D conversion port of the microcomputer 1.

FIG. 12 is a flowchart relating to error detection and its processing when setting the second threshold value of each photosensor. In the above-described embodiment and its modification, each time the second threshold value of each photosensor 4, 5 is calculated and set, the second threshold value of the photosensors 4, 5 is compared, and a predetermined value is set for both. If there is the above difference, it is judged that the setting is abnormal and the film is rewound. After the rewinding is completed, the processing shown in FIG. 12 is started. First, a counter that counts the number of times the second threshold is calculated and set is repeated is reset (S101), and the film feeding control is performed again to collect data (S102, S103). Second photo sensor 5
The second threshold value is calculated (S104), and it is confirmed whether or not the setting of the second threshold value of the first photosensor 4 is completed (S105). If the setting of the second threshold value of the first photo sensor 4 is completed, the second threshold values of the first photo sensor 4 and the second photo sensor 5 are compared, and it is determined whether the difference between the two is within a predetermined value. It is determined (S106). When it is within the predetermined value, both second threshold values are judged to be normal, the number of perforation edges detected by the first photosensor 4 is counted (S107), and when the predetermined number is reached, the feeding motor M is turned on. Stop (S108). As a result, the first frame B1 of the film is set at a predetermined shooting position. In addition,
In this embodiment, the predetermined number of edge counts is four. On the other hand, when the difference between the second threshold values of the first photo sensor 4 and the second photo sensor 5 is larger than the predetermined value, the feeding motor M is stopped and the film winding is stopped. Further, the feeding motor M is reversely rotated to start film rewinding (S109). When the film is rewound into the cartridge (S110), the rewinding process is ended (S11).
1). Next, the counter is incremented (S11
2) It is determined whether or not the count value is a predetermined value (S11
3) If a normal value is not obtained even after repeating the second threshold value calculation and setting process a predetermined number of times, the counter is reset (S114) and a warning is given (S115). The standard for determining whether the setting of the second threshold value is abnormal is ± 0.5.
Assuming V, the second of the second photosensor 5 that has been previously calculated
If the second threshold value of the first photosensor 4 calculated subsequently is within the range of ± 0.5 V around the threshold value, it is determined to be normal and the setting process ends. On the other hand, when the value is out of the range, the film is rewound and the data collection and the calculation of the second threshold value are repeated a predetermined number of times, for example, three times, until the film falls within the allowable range, and even if it is repeated three times, it does not fall within the allowable range. In this case, it is judged to be abnormal due to a circuit failure or the like, the film is rewound to end all the processes, and a warning is given.

In the above-described embodiment and its modification, the circuit of the photosensors 4 and 5 shown in FIG.
An example in which the output of the photosensors 4 and 5 becomes the Lo level when the film is detected, that is, when the photosensors 4 and 5 are blocked by the film and the incident light amount decreases, is shown in FIG.
With the circuit shown in FIG. 3, the outputs of the photosensors 4 and 5 can be set to the Hi level when the film is detected. In the circuit shown in FIG. 13 (a), the output voltage of the photosensors 4 and 5 is sent to the A / D conversion port of the microcomputer 1, and the microcomputer 1 calculates the second threshold value and the perforation of the film and the perforation. To detect. Further, in the circuit shown in FIG. 13B, the output voltages of the photosensors 4 and 5 are sent to a comparator and compared with a reference voltage set by the microcomputer 1 to detect the leading edge of the film and perforation. In this case, the second threshold value is calculated by directly fetching the output voltage of the photosensors 4 and 5 from the A / D conversion port of the microcomputer 1.

In the configuration of the above embodiment, the photosensors 4 and 5 are photosensors, the photosensor 4 is the first photosensor, the photosensor 5 is the second photosensor, and the microcomputer 1 is the perforation detection means. The leading edge detection means, the threshold value setting means, the first threshold value setting means and the second threshold value setting means constitute the film feeding motor control device 3 and the motor M, respectively.

[0025]

【The invention's effect】

(1) As described above, according to the present invention, the output signal of the photo sensor is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of the photo sensor before the leading edge of the film is detected. The threshold value for perforation detection is set based on the output signal of the photo sensor after detecting the leading edge of the film. Then, the output signal of the photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. Therefore, there is no case where the film exists at the detection position of the photosensor. In this case, the output signal of the photo sensor can be accurately detected, and even if there is a difference in the reflection amount depending on the film, the optimum threshold value can be set for the loaded film, and the perforation can be detected accurately. The film feeding accuracy can be improved. (2) The output signal of the photo sensor is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of the photo sensor before detecting the leading edge of the film and a predetermined time after the leading edge of the film is detected. A threshold for perforation detection is set based on the output signal of the photo sensor after that. Then, the output signal of the photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. Therefore, there is no case where the film exists at the detection position of the photosensor. In this case, the output signal of the photo sensor can be accurately detected, and even if there is a difference in the reflection amount depending on the film, the optimum threshold value can be set for the loaded film, and the perforation can be detected accurately. The film feeding accuracy can be improved. (3) The output signal of the photosensor disposed closest to the winding spool of the camera is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of each photosensor before the leading edge of the film is detected. , The threshold value for perforation detection is set based on the output signal of each photosensor after detecting the leading edge of the film. Then, the output signal of each photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. You can accurately detect the output signal of the photo sensor when there is no
Even if there is a difference in the reflection amount depending on the film, the optimum threshold value can be set for the loaded film, and the perforation can be accurately detected and the film feeding accuracy can be improved. (4) The output signal of the photosensor arranged closest to the cartridge is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of each photosensor before the leading edge of the film is detected and the output signal of the film. A threshold value for perforation detection is set based on the output signal of each photosensor after a predetermined time has elapsed since the tip was detected. Then, the output signal of each photosensor is compared with a threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. You can accurately detect the output signal of the photo sensor when there is no
Even if there is a difference in the reflection amount depending on the film, the optimum threshold value can be set for the loaded film, and the perforation can be accurately detected and the film feeding accuracy can be improved. (5) 1st placed on the winding spool side of the camera
The output signal of the photo sensor of No. 1 is compared with a temporary threshold value to detect the leading edge of the film, and the output signal of the second photo sensor arranged on the cartridge side before the film is sent out from the cartridge, The threshold value of the second photo sensor is set based on the output signal of the second photo sensor when the leading edge of the film is detected by the photo sensor of. In addition, the first photosensor based on the output signal of the first photosensor before the film is sent out from the cartridge and the output signal of the first photosensor at the time when the perforation of the film is detected by the second photosensor. Set the threshold of the photo sensor. Then, the output signal of each photosensor is compared with each threshold value to detect the perforation of the film, and the film is fed based on the perforation detection result. Therefore, the film is present at the detection position of the photosensor. It can accurately detect the output signal of the photo sensor with and without the photo sensor, and can set the optimum threshold value for the loaded film even if there is a difference in the reflection amount depending on the film, and the perforation is accurate. It is possible to improve the film feeding accuracy by detecting.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment.

FIG. 2 is a view showing a leader portion of a film sent out from a tongue-less film cartridge.

FIG. 3 is a time chart showing outputs of first and second photosensors.

FIG. 4 is a flowchart showing film feeding control.

FIG. 5 is a flowchart showing a modified example of film feeding control.

FIG. 6 is a flowchart showing a modified example of film feeding control, which is subsequent to FIG. 5;

FIG. 7 is a flowchart showing another modified example of film feeding control.

FIG. 8 is a flowchart showing another modified example of film feeding control.

FIG. 9 is a flowchart showing another modified example of the film feeding control.

FIG. 10 is a flowchart showing a film feeding control continued from FIG. 9;

FIG. 11 is a circuit diagram of first and second photosensors.

FIG. 12 is a flowchart showing error detection and its processing when setting the second threshold value of the first and second photosensors.

FIG. 13 is another circuit diagram of the first and second photosensors.

[Explanation of symbols]

 1 Microcomputer 2 Storage Device 3 Film Feed Motor Control Device 4 First Photo Sensor 5 Second Photo Sensor 6 Timer 7 Photometric Device 8 Distance Measuring Device 9 Flash Device

Claims (13)

[Claims] 1. A photosensor which is installed at a perforation passage position of a film and which outputs a signal of a level according to an amount of received light, and compares the output signal of the photosensor with a threshold value to detect the perforation of the film. A film feeding device for a camera, comprising: a perforation detecting means; and a film feeding means for feeding the film based on a perforation detection result by the perforation detecting means, wherein the film feeding means cartridges the film. A leading edge detection unit that detects the leading edge of the film by comparing the output signal of the photosensor with a preset temporary threshold value when the sheet is fed from the leading edge detection unit before and after the leading edge detection by the leading edge detection unit. The threshold value based on the output signal of the photo sensor Camera film feed device, characterized in that it comprises a constant to threshold value setting means. 2. A photosensor which is installed at a perforation passage position of the film and outputs a signal of a level according to the amount of received light, and compares the output signal of the photosensor with a threshold value to detect the perforation of the film. A film feeding device for a camera, comprising: a perforation detecting means; and a film feeding means for feeding the film based on a perforation detection result by the perforation detecting means, wherein the film feeding means cartridges the film. The leading edge of the film by detecting the leading edge of the film by comparing the output signal of the photosensor with a preset temporary threshold value when the sheet is sent from the leading edge of the film, and the leading edge of the film is detected by the leading edge detecting means. The output signal of the photo sensor before the Camera film feed device, characterized in that it comprises tip from the detection and threshold value setting means for setting the threshold based on an output signal of the photo sensor after a predetermined time. 3. A plurality of photosensors, which are installed before and after the perforation passage position of the film in the film feeding direction and output a signal of a level according to the amount of received light, and a threshold value for the output signal of each photosensor. A film feeding device for a camera, comprising: perforation detection means for detecting the perforation of the film in comparison with, and film feeding means for feeding the film based on the perforation detection result by the perforation detection means. When the film is fed out of the cartridge by the film feeding means, the output signal of the photosensor arranged closest to the winding spool of the camera among the plurality of photosensors is set to a preset temporary threshold value. A leading edge detection means for detecting the leading edge of the film in comparison A film feeding apparatus for a camera, further comprising: threshold setting means for setting the threshold based on output signals of the photosensors before and after the leading edge detection means detects the leading edge. . 4. A plurality of photosensors, which are installed before and after the perforation passage position of the film in the film feeding direction and output a signal of a level according to the amount of received light, and a threshold value for the output signal of each photosensor. A film feeding device for a camera, comprising: perforation detection means for detecting the perforation of the film in comparison with, and film feeding means for feeding the film based on the perforation detection result by the perforation detection means. When the film is fed from the cartridge by the film feeding means, the output signal of the photosensor arranged closest to the cartridge among the plurality of photosensors is compared with a preset temporary threshold value. And a tip detecting means for detecting the tip of the film, The threshold is based on the output signal of each photosensor before the leading edge of the film is detected by the edge detection means and the output signal of each photosensor after a predetermined time has elapsed since the leading edge of the film was detected. A film feeding device for a camera, comprising: a threshold setting means for setting a value. 5. A first device, which is installed on a winding spool side of a camera in a film feeding direction at a film perforation passing position, and which outputs a signal of a level according to an amount of received light.
Of the photosensor, a second photosensor installed on the cartridge side in the film feeding direction at the perforation passage position of the film and outputting a signal of a level according to the amount of received light, and output signals of the photosensors. A film feeding apparatus for a camera including a perforation detecting unit that detects a perforation of the film by comparing it with a threshold value, and a film feeding unit that feeds the film based on a perforation detection result by the perforation detecting unit. A tip for detecting the leading edge of the film by comparing the output signal of the first photosensor with a preset temporary threshold value when the film is fed from the cartridge by the film feeding means. The film is detected by the detecting means and the film feeding means. The second photosensor based on the output signal of the second photosensor before being sent out from the cartridge and the output signal of the second photosensor at the time when the leading edge of the film is detected by the leading edge detecting means. Second threshold value setting means for setting the threshold value of the photo sensor, the output signal of the first photo sensor before the film is sent out from the cartridge by the film feeding means, and the second The first time point when the perforation is detected by the perforation detecting means using the threshold value set by the threshold value setting means
And a first threshold value setting means for setting the threshold value of the first photosensor based on the output signal of the photosensor. 6. The camera film feeding apparatus according to claim 1, wherein the photo sensor is a reflection type photo interrupter or a photo reflector. apparatus. 7. The film feeding device for a camera according to claim 1, wherein the photosensor is a transmissive photointerrupter or a photoreflector. apparatus. 8. The film feeding device for a camera according to claim 1, wherein the perforation detecting means and the leading edge detecting means have a comparator, and the temporary threshold value is provided in the comparator. And a film feeding apparatus for a camera, wherein a reference voltage corresponding to the threshold value is applied. 9. The film feeding device for a camera according to claim 1, wherein the perforation detection means and the leading edge detection means perform A / D conversion on an output signal of the photosensor.
A film feeding apparatus for a camera, comprising: an A / D converter, and a microcomputer for comparing an output signal of the A / D converter with the temporary threshold value and the threshold value. 10. The film feeding device for a camera according to claim 1, wherein the output of the photosensor before the leading edge of the film is detected by the leading edge detecting unit is the film. A film feeding device for a camera, wherein the threshold value setting means detects the film before the film is fed out of the cartridge by the feeding means. 11. The film feeding device for a camera according to claim 3, wherein the temporary threshold value is set commonly to the plurality of photosensors. Film feeding device for camera. 12. The film feeding device for a camera according to claim 3, wherein a threshold value is set when the difference between the threshold values set for the photosensors is a predetermined value or more. A film feeding device for a camera characterized by being abnormal. 13. The film feeding device for a camera according to claim 12, wherein when the threshold setting is abnormal, the film is rewound into the cartridge and then the film is fed again. A film feeding device for a camera, which performs a value setting process.