JPH0227650B2 - FUIRUMUJOHOOJIDOTEKINYOMIKOMUKAMERA - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a camera that automatically reads information from a film information recording section provided in a reader section.

Conventionally, film exposure index (commonly known as film sensitivity), number of exposures, film type (black and white, color,
Negative, reversal, etc.) film information had to be manually set in the camera one by one, and if the setting was incorrect, problems such as improper exposure occurred. In order to completely prevent such failures, a system can be considered in which film information is recorded on the film itself, and when the camera is loaded with the film, the camera automatically reads that information and completes the setting. .

FIG. 1 shows an example of a film having such an information recording section, and the leader section 2 of the film 1 has the following information:
An information recording section 5 consisting of an array of holes 4 drilled between the perforations 3 is provided. The holes 4 record the film sensitivity, the number of exposures such as 12 shots, 24 shots, etc., and other film characteristics, such as color black and white, reversal, or negative, depending on the presence or absence of holes in binary format and their combination. are doing. Information recording section 5 consisting of this array of holes 4
In order for the camera to read this information optically, the film is fed by placing a light emitter that emits light toward the hole 4 on one side of the film, and a photoreceptor that receives the light that passes through the hole 4 on the other side. A method for detecting changes in the output of the photoreceptor due to changes in the output of the photoreceptor, and a photoreceptor and an emitter on one side of the film, and a reflector with a different reflectance from the film on the other side, so that the light emitted from the emitter passes through the hole. There is a means for similarly receiving the light returning from the reflector and the light reflected by the film surface on the photoreceptor.

By the way, in both methods, while the light emitting body is projecting light onto the information record 5 of the film reader section, no screen is formed on the leader section, so the projected light does not have a negative effect on the film. When the information recording section 5 passes through an information reading section including a light emitter and a photoreceptor and the photographic screen approaches the information reading section, the light from the light emitter becomes harmful to the screen.

In the present invention, in order to detect that the film information recording section has passed through the optical film information reading section,
A film loading detection switch, a pulse generator that generates a number of pulses according to the amount of film movement from a member that rotates or moves as the film is fed, and a light receiving system of an optical film information reading section detect the film information. A counter that counts the pulses generated by this pulse generator from the time the first pulse of the recording section is detected, and a counter that turns on the light emitting source of the light projection system of the optical film information reading section when the film loading detection switch is turned on. A switch circuit is provided to turn off the light emitting source when the number of counting pulses reaches a predetermined constant number, and the light emitting source is surely turned off when the film information recording section passes through the optical film information reading section. It is characterized by the fact that
In addition, the light emitting source can be turned off even when a film that does not have a film information recording section is loaded.
A light-off circuit can be provided to turn the light off.

The invention will now be described with reference to the illustrated embodiments. 2 to 4 show a first embodiment of the present invention, in which a light emitting source 10 of an optical film information reading section is shown.
is provided in a sprocket 11 that rotates as the film is fed. The sprocket 11 is rotatably fitted to a fixed shaft 12 at the center, and the fixed shaft 12 has a shaft space 13 in which the light emitting source 10 is housed.
Radial optical paths 14a and 14b are provided for guiding the light from the light emitting source 10 to the film 1 side and the opposite side. On the other hand, the sprocket 11 is provided with radial optical paths 16 that can communicate with the radial optical paths 14a and 14b, respectively, between the teeth 15 that fit into the perforation 3 of the film. A film information reading light receiving section 17 and a counter light receiving section 18 are provided outside the sprocket 11 in correspondence with the radial optical paths 14a and 14b of the fixed shaft 12. The film information reading light receiving section 17 receives light from the light emitting source 10 through the radial optical paths 14a and 16 and the hole 4 of the film information recording section 5. The film information is then read out.

A film loading detection switch 20 is provided near the sprocket 11, as shown in FIG. This detection switch 20 is turned on and off by a presser 22 supported on the film guide plate 21.
The presser 22 is normally projected toward the pressure plate 24 by a spring 23 to turn off the switch 20, and when pressed by the film 1 turns the switch on. The detection switch 20
When turned on, the main power of the camera is turned on, and at the same time, the light emitting source 10 is turned on via the switch circuit 25.

Therefore, the switch circuit 25 of the light emitting source 10 is given the OFF signal of the light emitting source first by the light receiving section 1.
a counter start signal generation circuit 27 that provides a start signal to the counter 26 when an output occurs at the counter 7;
The counter 26 and preset counter 2 count each time an output is generated in the counter light receiving section 18.
8, and preset counter 28 and counter 2
A comparison circuit 29 compares the outputs of 6 and provides an OFF signal to the switch circuit 25 when the two match.

The camera configured as described above operates as follows to control ON/OFF of the light emitting source 10. First film 1
When loaded into the camera, the detection switch 20 is turned on as described above, and the light emitting source 10 is turned on via the switch circuit 25. Next, when feeding of the film 1 is started by a well-known film winding mechanism,
Eventually, the first hole (information recording section start instruction hole) 4a of the information recording section 55 is located between the light emitting source 10 and the light receiving section 17 for reading film information (FIG. 3).
Then, the light from the light source 10 follows the radial optical path 14a, 1
6 and the hole 4a to reach the light receiving section 17, and the light receiving section 17 is connected to the counter start signal generating circuit 27.
to output the counter start signal to the counter 26.
give to

The light from the light source 10 is transmitted through radial optical paths 14b and 1
6 to the counter light receiving section 18 on the opposite side from the light receiving section 17. Since the radial optical path 16 of the sprocket 11 is provided between the teeth 15, the light given to the counter light receiving section 18 is intermittent in synchronization with the feeding of the film, and the light receiving section 18 receives light every time it receives light. A count signal is given to the counter 26.

In the preset counter 28, a number corresponding to the length of the film information recording section 5 is registered. That is, since the length of the information recording section 5 is constant, the length is registered in advance in the preset counter 28 as the number of perforations 3 provided for film feeding or the number of gaps between perforations. I'll keep it.

Therefore, as the film is fed, the counter 26
If the comparator circuit 29 detects that the count number given to and integrated matches the number registered in the preset counter 28, and the match signal is used to send an OFF signal for the light emitting source 10 to the switch circuit 25, the information is It reliably detects that the recording section 5 has passed through the optical information reading section, and immediately turns on the light emitting source 10.
Can be turned off.

5 and 6 show a second embodiment of the invention. This embodiment differs from the first embodiment in that both the light emitting source and the light receiving section of the optical information reading section are provided on one side of the film 1. In the illustrated example, the light emitting body and the light receiving section are integrated. A photocoupler 30 is used. A photocoupler 30 is provided on the camera back plate 31 so that the film 1 is positioned between the coupler and the sprocket 11, and a photocoupler 30 is provided on the body between the teeth of the sprocket 11 to determine the reflectance of the film 1. Reflection plates 32 with clearly different reflectances are attached. Therefore, the film 1 is loaded and the photocoupler 30 is passed through a loading detection switch 20 and a switch circuit 25 similar to those shown in FIG.
The light emitter is turned on, and then film feeding is started and the hole 4 of the information recording section 5 is connected to the photocoupler 3.
When reaching the 0 portion, the light emitted from the photocoupler 30 and passing through the hole 4 is reflected by the reflection plate 32 and reaches the photoreceptor of the photocoupler 30. Since the reflectance of the reflector 32 is different from that of the film 1, film information can be read by detecting the output of the photocoupler 30 in synchronization with the feeding of the film. Similarly to the first embodiment, the photocoupler 30 also provides an output to the counter start signal generation circuit 27 at the output when the first hole 4a comes.

Detection of the film feeding amount, that is, detection of passage of the information recording section 5, is carried out by a gear 33 provided integrally with the sprocket 11, a gear 34 meshing with this gear 33, and a Hall element drive circuit 35 opposing this gear 34. This is performed by the driven magnetoelectric transducer 36, the waveform shaping circuit 37 of the magnetoelectric transducer 36, the counter 26, the counter start signal generation circuit 27, the preset counter 28, and the comparison circuit 29 similar to the first embodiment.

The magnetoelectric conversion element 36 facing the gear 34 generates a pulsating current every time one tooth passes in front of the element as the gear 34 rotates, and this pulsating current is converted into a pulse by the waveform shaping circuit 37 and sent to the counter 26. Given. Therefore, by registering the number of teeth of the gear 34 corresponding to the length of the information recording section 5 in the preset counter 28, the information recording section 5 can pass through the photocoupler 30 section in exactly the same way as in the first embodiment. detects that
The photocoupler 30 can be turned off immediately.

Note that the photocoupler 30 and the reflecting plate 32 do not necessarily need to be provided at the sprocket 11, which rotates in synchronization with the film feeding. For example, as shown in FIG. 7, the same function as described above can be obtained by providing a photocoupler 30 on the pressure plate 24 and a reflecting plate 32 on the film guide plate 21, respectively. However, in this case, means for identifying the hole 4 of the information recording section 5 and the perforation 3 is separately provided.

Figures 8 and 9 show that the light emitting source is turned off when a film with no film information record 5 is loaded.
This is an example of a camera that can be used as a camera.

That is, the film loading detection switch 20 detects when a film is loaded regardless of the presence or absence of the information recording section 5.
Since it is turned on, the light emitting source of the information reading section lights up. However, if the film information recording section 5 does not exist, the light emitting source cannot be used in the cameras shown in the above two embodiments.
It cannot be turned off, and the film screen is therefore exposed to unnecessary and harmful light.

FIGS. 8 and 9 each show an embodiment that solves such inconveniences. In FIG. 8, the structure of the embodiment of FIG. second counter 4
0 and a second preset counter 41 paired with this second counter 40, both counters 40,
The outputs of 41 are compared by a comparison circuit 29. In the second preset counter 41, the number of teeth of the gear 34 corresponding to the distance from the leading edge of the film to the first hole 4 of the film information recording section 5 plus alpha is registered in advance. Then, when the film is loaded and feeding starts, the magnetoelectric transducer 36 and the waveform shaping circuit 37 immediately start the second counter 4
A count of 0 is started, and when the counted number matches the registered value of the second preset counter 41, the comparison circuit 29 outputs a light-off signal to the switch circuit 25, and the switch circuit 25 is activated, causing the photocoupler 30 to emit light. The body lights out.

In this embodiment, if the counter 26 and the preset counter 28 enter the operating state before the comparison operation between the second counter 40 and the second preset counter 41 is started and a match signal is output, the comparison operation is started. Detected, the comparison operation of counters 40 and 41 is canceled. Alternatively, the number registered in the second preset counter 41 is set to be sufficiently larger than that in the preset counter 28 (but smaller than the number commensurate with the feeding distance up to the photographing start screen). Note that according to this latter method, it is possible to deal with both films with and without information recording parts without providing a passage detection device for the information recording part, but the light emitting source is immediately turned off when the information recording part passes. It is not possible to do so. The same applies to the case where the light emitting source is controlled by a switch circuit that is turned on when a film is loaded and turned off when the number of sheets counter reaches 0 or -1.

The embodiment shown in FIG. 9 has the components shown in FIG. 5 provided with a timer 43 that starts operating in response to a pulse from the waveform shaping circuit 37. Photo coupler 30 lit by film loading detection switch 20
The timer 43, which starts at the same time as the gear 34 starts rotating, starts the switch circuit 2 after the set time has elapsed.
5 to turn off the photocoupler 30.

Note that the means for detecting the film feeding distance is limited to one that uses the magnetoelectric conversion element 36, but may also be a photoelectric conversion device as shown in FIG. 2, a mechanical device using pins or tentacles, etc. Of course.

In summary, the present invention detects when the information recording section of the film passes through the information reading section by using a film loading detection switch, a pulse generator that generates a number of pulses corresponding to the amount of movement of the film, and pulses generated by this pulse generator. Since the light emitting source of the information reading section is turned off based on this detection signal, the light emitting source of the information reading section does not have an adverse effect on the photographic screen. Furthermore, if a light-off circuit is provided to turn off the light emitting source of the information reading section after a certain feeding distance or a certain period of time after starting feeding after loading the film, it is possible to handle films that do not have an information recording section.

[Brief explanation of drawings]

Fig. 1 is a front view showing an example of a film having an information recording section, Figs. 2 to 4 show a first embodiment of the camera of the present invention, and Fig. 2 is a partially perspective view. System connection diagram, Fig. 3 is a cross-sectional view of the sprocket section showing the vicinity of the information reading section, Fig. 4 is a cross-sectional view showing an example of the film loading detection switch, and Fig. 5 is a cross-sectional view of the sprocket section showing the vicinity of the information reading section.
The figure is a system connection diagram showing a second embodiment of the camera of the present invention, with a part thereof being a perspective view. Figure 6 is a cross-sectional view of the sprocket part showing the vicinity of the information reading part. A sectional view showing another installation example, and FIGS. 8 and 9 are system connection diagrams each showing a partially perspective view showing another embodiment of the present invention. 1... Film, 2... Leader section, 4... Hole,
5... Information recording section, 10... Light emitting source, 11... Sprocket, 17... Light receiving section for reading film information, 18... Counter light receiving section, 20... Film loading detection switch, 25... Switch circuit, 30
...Photocoupler, 32...Reflector.

Claims (1)

[Scope of Claims] 1. A camera that reads information from a film information recording section formed by the presence or absence and arrangement of rows of holes in a leader section of a film, the camera comprising: an optical film information reading section having a film loading system and a light receiving system; a film loading detection switch; a pulse generator that generates a number of pulses according to the amount of film movement from a member that rotates or moves as the film is fed; a counter that counts the pulses generated by the pulse generator from the time when the light receiving system of the optical film information reading section detects the first pulse of the film information recording section; A switch circuit for turning on a light emitting source of a light projecting system of the information reading section and turning off the light emitting source when the count pulses of the counter reach a predetermined constant number. Cameras that automatically load. 2. In claim 1, the film information is further provided with an extinguishing circuit that turns off the light emitting source of the projection system after a certain feeding distance or a certain time after starting film feeding after loading the film. camera to be loaded.