JPH04120529A - Film feeding device for camera - Google Patents

Abstract

PURPOSE:To improve reliability of reverse control by carrying out permitting and inhibiting setting of a second feeding mode photographing an unexposed frame while winding back by two frames each based on outputted signal from a frame information reading means after completion of winding up. CONSTITUTION:When a frame loaded by the film information reading means (a) is judged to be a film with a DX code, setting of the feeding mode by two frames each is permitted, and selection of the feeding mode is carried out by a setting means (b). Then, if the feeding mode by two frames each is not set, the same control as for the film without the DX code is carried out thereafter, and if the feeding mode by two frames each is set, a film feeding means (g) is controlled to wind up the film by two frames each synchronized with a photographing operation by a winding control means (d) based on the number of DX code films and the outputted signal of a frame detection means (c). Thus, improvement of the reliability of the reverse control is obtained, exposure can be carried out correctly, and double exposure can be eliminated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a film feeding device that winds and rewinds a film using an electric motor, and in particular, takes a picture while winding it one frame at a time, and then rewinds the film after shooting is completed. During the first feed, film is taken while winding two frames at a time, and after winding is completed, the film feed is reversed and unexposed frames are taken while rewinding two frames at a time. The present invention relates to a film feeding device for a camera having a J2 feeding mode.

[Conventional technology]

Conventionally, a film feeding device that efficiently feeds a film by feeding it two frames at a time is described in Japanese Patent Application Laid-Open No. 1-202723, and as shown in FIG. It is comprised of a frame signal generating means 100 for frame identification, a winding control means 200 for winding two frames at a time, a reversing control means 500 for reversing the film, and a rewinding control means 400 for rewinding two frames at a time.

Conventional film feeding devices are configured as described above, so in the mode that feeds two frames at a time, the film is taken while winding two frames at a time, and after winding is complete, the film feeding is reversed and the film is rewound two frames at a time. It is now possible to shoot unexposed frames while

Note that the reversal control means 500 has a method of controlling based on the amount of winding when the final exposure frame of winding is detected;
A method is used in which the final exposure frame is determined and controlled based on the film DX code and the number of frames to be wound.

[Problems to be Solved by the Invention] However, in the conventional example described above, although a film feeding device and a film feeding control method for feeding the film two frames at a time have been considered, the type of film loaded is This can lead to double exposure, a fatal accident for the camera. In other words, there are two methods for controlling reversal at the end of winding: a control method that uses the number of DX-coated films, and a control method that uses the winding amount at the time of winding and tension. After tensioning, the film may return or the amount of return may vary, so the start position of rewind may change after the film feed is reversed, and in some cases this may cause a fatal flaw, such as overlapping the frame taken during film reversal. There were problems with control reliability.

Therefore, in the present invention, exposure is performed correctly in a film feeding mode in which the film is filmed while being wound two frames at a time, and after the winding is completed, the film feeding is reversed, and the unexposed frame is taken while being rewound two frames at a time.
That is, it is an object of the present invention to provide a film feeding device for a camera that does not cause double exposure.

[Means to solve the problem]

In order to achieve the above object, the present invention includes: a film feeding means for winding and rewinding a film using an electric motor; a frame detection means for identifying frames of the film; a film winding control means for controlling the winding of the film; A film rewinding control means for controlling the rewinding of the film, a film loading detection means for detecting the loading of the film, a reversing control means for reversing the feeding at the end of winding of the film and starting rewinding, and a reversing control means for controlling the film information. It has a first feeding mode in which it takes pictures while winding one frame at a time and then rewinds after the shooting is completed, and a second feeding mode in which it takes pictures while winding two frames at a time and reverses the film feeding after finishing winding. The second step is to rewind frame by frame and shoot unexposed frames.
The invention according to claim 2, wherein the camera is configured such that the setting of the second feeding mode is permitted or prohibited based on an output signal from the film information reading means. If the film information reading means determines that the loaded film is a DX coded film, the setting of the second feeding mode is permitted;
If it is determined that the film does not have a DX code, the setting of the second feeding mode is prohibited.

(Function) Since the present invention is configured as described above, first, the film information reading means determines whether or not the loaded film has a DX code, and in the case of a film without a DX code, two frames each are Setting the feeding mode is prohibited,
Based on the output signal of the frame detection means that identifies one frame as the film is fed, the film feeding means is controlled by the winding control means so as to wind the film in synchronization with the photographing operation. When the loaded film is determined to be a DX coded film by the film information reading means, the setting of a feeding mode of two frames at a time is permitted, and the setting means selects the feeding mode;
If the feeding mode of 2 frames at a time is not set,
Thereafter, the same control as for film without a DX code is performed, and once the feeding mode of 2 frames at a time is set, the winding control means based on the number of DX code films and the pressure signal of the frame detection means feeds 2 frames at a time in synchronization with the shooting operation. The film feeding means is controlled to wind the film. Thereafter, when the reversing control means f detects the end of winding, the film feeding is reversed to start rewinding, and the rewinding control means controls the film feeding means to rewind the film two frames at a time.

〔Example〕

Examples of the present invention will be described below. FIG. 1 is a control block diagram for controlling the film feeding means g.
According to this embodiment, the control device is composed of film information reading means, setting means b, frame detection means C, winding control means d, rewinding control means e, and reversing control means f, and each of these means is shown in FIG. The film feeding means g is controlled by performing the functions described in the flowchart of FIG.

The appearance of the camera body or main body is as shown in Figure 5.
It is almost the same as the conventional one. That is, the outer shape is approximately a rectangular parallelepiped, and the cartridge chamber 43 is provided with a film information reading device 44. Further, a frame detection sensor or frame detection device 36 is provided near the photographing frame.

As shown in FIG. 4, the frame detection device 36 includes a light emitting section 38a and a light receiving section 36b. is reflected on the film 29,
The light is received by the light receiving section 38b and the sensor 36 is turned on. When the film 29 is further fed and the holes of the perforations 47 of the film 29 come to the front of the sensor 36, the light emitting part 36a
Since more intense light passes through and is no longer reflected, the sensor 36 is turned off. The pressure signal is shown in FIG. Signal O
N, OFF 8 times, that is, hole 8 of perforation 47
represents one frame.

At the top of the camera body, there is a feeding mode switching dial 34 for switching the film feeding mode, and on the right side there is a spool 37 driven by an electric motor.
is provided. Also provided below are a rewind start switch 40°, a feed mode call switch 41, and the like.

Next, the operation of the above embodiment will be explained with reference to the flowchart shown in FIG.

In step 1, put the film case 46 into the cartridge chamber 43, place the tip of the film 29 on the spool 30, and
31 is closed, the film 29 is pressed by the pressure plate 32, and when the film SW 33 is turned on (FIG. 3), autoloading in step 2 is started.

Next, initial values necessary for control in setting the feeding mode of two frames at a time are set (step 3). Then, in step 4, the film information reading device 44 determines whether or not the film loaded in the camera has a DX code, and if the film does not have a DX code, step 8
If the film has a DX code, go to step 5. D
In the case of film without an X code, the setting of the feeding mode of two frames at a time is prohibited, so the process immediately goes to step 8. If you want to forcefully rewind the film, press Rewind 5.
W40 is turned ON and film rewinding is started.

If rewinding is not to be performed, proceed directly to step 9, and if the SWI is OFF, the standby state continues. When the release button is pressed down one step and the SWI (switch 1) is turned ON, photometry is performed in steps 10, 11, and 12. Distance measurement and lens driving are performed sequentially or simultaneously, and SW2
is in a standby state. When the release button is further pressed down and SW2 (switch 2) is turned on, step 14
A battery check is performed at step 2, and if the battery capacity is low, a battery warning is issued at step 22, and if the battery is sufficient, shutter drive is started (step 15). At the same time as SW2 is turned off (step 16), shutter charging is performed (step 17).

In step 18, it is determined whether S=2. That is, when S≠2, that is, when it is not set to feed 2 frames at a time in step 5 even for a film without a DX code or a film with a DX coat, the process proceeds to step 19, and the film is wound one frame at a time. Re,
When it is detected in the next step 20 that film photography has ended, the film is rewound (step 21). If the end of film shooting is not detected, go to step day. If one or more releases are completed here,
Setting the feeding mode for two frames at a time is not possible (prohibited). When S=2 in step 18, that is, 2 in step 5
When set to frame-by-frame feeding mode, step 23
go to. Since R=φ has been initialized in step 3, the process goes to step 24, and winding of the film two frames at a time is started. If winding completion detection is OFF, return to step 8. When the winding end detection is turned ON and the film feeding is reversed in the rewinding direction, R=1 in step 26.
Then, go to step 8. From then on, steps 8 to 23 proceed in the same way, and since R=1, step 27
Rewinding the film two frames at a time is started, and if the end of shooting is not detected in step 28, steps 8 to 27 are repeated again, and when the end of shooting is detected in step 28, the rewinding of the film is started in step 21. film rewinding begins.

〔Effect of the invention〕

As described above, according to the present invention, the film feeding means is controlled by the film information reading means, so that the film information reading means determines whether or not a film with a DX code is loaded. In this case, the setting of the two-frame film feeding mode is prohibited, and the setting is permitted only when a film without a DX code is loaded. The film reversal control when the film is fed two frames at a time is controlled by DX.
The number of code films is used to accurately determine the rewinding start position after reversal, and the film rewinding start position after reversal does not change due to film tension. Therefore, there is an effect that the reliability of reversal control is increased. Furthermore, since the film information reading means determines whether or not the film feeding mode can be set, the control system can be simplified and the software load can be reduced.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a control example of an embodiment of the present invention, Fig. 2 is a flowchart showing its operation, Fig. 3 is a plan view showing an example of automatic film loading, and Fig. 4 is a film detection means. 5 is a perspective view of a camera according to the present embodiment, FIG. 6 is an explanatory diagram showing an example of a film frame detection switch, and FIG. 7 is a control block diagram showing a conventional example. . 33...Film loading detection switch 36...Frame detection sensor 44...Film information reading device and other 4 people

Claims (1)

[Scope of Claims] 1. Film feeding means for winding and rewinding the film using an electric motor, frame detection means for identifying frames of the film, film winding control means for controlling the winding of the film, and film rewinding means. a film rewinding control means for controlling film rewinding, a film loading detection means for detecting film loading, a reversing control means for reversing the feeding at the end of film winding and starting rewinding, and a film information reading means for reading film information. There is a first feeding mode in which the film is filmed while winding one frame at a time and then rewinded after the film is finished, and a first feeding mode in which the film is filmed while winding two frames at a time, and after winding is completed, the film feed is reversed and the film is rewound two frames at a time. In a camera capable of switching between a second feeding mode and a second feeding mode for photographing unexposed frames, the setting of the second feeding mode is permitted or prohibited based on an output signal from the film information reading means. Features of the camera's film feeding device. 2. If the film information reading means according to claim 1 determines that the loaded film is a film with a DX code, the setting of the second feeding mode is permitted, and if it determines that the loaded film is a film without a DX code, the setting of the second feeding mode is permitted. A camera film feeding device characterized in that it is prohibited.