JPS62151830A - Blank feed controller for camera - Google Patents

Abstract

PURPOSE:To take up a film automatically by rewinding all the film into a film cartridge if the film is tensed when a cover for film loading is opened or closed by mistake and a blank feed is made again. CONSTITUTION:When the cover for film loading is opened and closed by mistake and the output of a counter 36 goes up to a high level, the output of an AND gate 39 also rises. Then, the output of a NAND gate 27 goes down to a low level although the output of a NAND gate 14 is latched at the high level; and latch outputs of NAND gates 28 and 29 go up to the high level and the output of a OR gate 30 also rises. Consequently, a rewinding circuit 31 is excited to rewind the film. When the film is all rewound, the circuit 31 outputs a high-level signal and the output of a NOR gate 33 falls to the low level, thereby resetting gates 14 and 15, and 28 and 29 constituting latch circuits. Consequently, when the film is tensed, the film is all rewound into the film cartridge automatically.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an improvement in a camera blank feed control device that automatically starts blank feed operation when film is loaded and the back cover is closed. .

[Background of the invention]

Conventionally, with cameras that have a front that automatically feeds the film, when the back cover is closed after the film is loaded, the camera automatically feeds, for example, four frames of film, completing preparations for shooting. It is configured to do so. In such a camera, even if the photographer accidentally opens the back cover after the film has been loaded, the camera back will close and the blank feed function will work again, allowing the film to be loaded again. However, if the film back is opened near the end of the film (for example, there are 3 frames or less remaining), the film drive motor will continue to run forever because the specified number of frames will not be fed. The energization in the direction of idle feeding remained in place, which had an adverse effect on the motor and the power supply battery. In view of this, a proposal has been made in which the energization time is determined, and when that time elapses, the energization to the motor is automatically stopped and a warning is issued.However, if the photographer notices the warning, The operator had to rewind the film himself, which was a pain.

[Purpose of the invention]

An object of the present invention is to solve the above-mentioned problems and provide a camera with a jump feeder front that can automatically wind the film without leaving the photographer to decide what action to take next. It is to be.

[Features of the invention]

In order to achieve the above objects, the present invention provides a blank feed control device that automatically feeds a film to a predetermined position when a film loading lid is closed, and detects that blank feeding is completed. a detection means, a dry feed completion storage means for storing the completion of the mosquito feed in response to the output of the mosquito dry feed detection means, a dry feed abnormality detection means for detecting that the mosquito feed has not been carried out normally; After the completion of the blank feed is stored in the feed storage means, the film loading lid is opened and closed, and when blank feeding is performed again, a signal indicating an abnormality in blank feeding is output from the blank feeding abnormality detection means. If the film is loaded, the film is fed in the opposite direction to the direction of the blank feed, so even if the film loading lid is opened/closed by mistake and the blank feed is performed again, the blank feed will continue normally. The present invention is characterized in that the entire film is wound into a film cartridge if the film is not wound.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

FIG. 1 is a circuit (2) showing one embodiment of the present invention. 1 is a film switch that is turned off when film is loaded, 2 is a back cover switch that is turned off when the back cover is closed, 3 is a release switch, and 4 is a release switch that is turned on when the back cover is closed, and the film feed is completed. A blank feed switch to be turned off, 5 is a manual wind switch, 6 to 10 is a pull-up resistor, 1) is an AND gate that outputs a high level signal when the film switch 1 and the back cover switch 2 are turned off, 12 is the Nantes gate, 13 is the inverter,
1.15 is a Nant gate that constitutes a rounding latch circuit that memorizes that the empty feed has been completed; 16 is a three-person AND gate; and 17 is a high-level signal input.
For example, a feed circuit that feeds four frames of film until the unexposed part is at the 9th position facing the photographic screen; 18, 19, and 21 are inverters; 22 is a known exposure control circuit; and 24 is a winding circuit. Circuit, 27 is Nantes gate, 28
．． 29 is a Nant gate that constitutes a latch circuit, 30 is an OR gate, 31 is a rewind circuit, 32 is an initial setting circuit that outputs an instantaneous signal when the power is turned on, 33 is a NOR gate, and 34 is a 1-pulse signal. 35 is an oscillation circuit, 36 is a counter for counting clock pulses from the oscillation circuit 35, and after being reset by the pulse signal from the one-shot circuit 34, a predetermined number of frames (4 frames are fed) When the number corresponding to the time required for transmission is counted, a high level signal is output from the output terminal Q. 37.59 is and gate, 3
8 is the or gate.

Next, the operation will be explained with reference to FIG. 2. After the back cover is opened and a film is loaded into the cartridge chamber (not shown), when the back cover is closed, the film switch 1 and the back cover switch 2 are opened. is turned off, and the output of AND gate 1) becomes a high level signal. Also, since the idle feed switch 4 is on, the output of the inverter 13 is a Heilepel signal. Furthermore, at this time, the rewind circuit 31 is not excited, that is, the output of the OR gate 30 is a low level signal, so the output of the inverter 1B is a high level signal. From the above, the output of the AND gate 16 is . . . A signal is generated, and the blank feed circuit 17 is operated to start the blank feeding operation of the film. When the blank feeding of the film for, for example, 4 frames is completed, the blank feed switch 4 is turned off, and the inverter 13 is turned off. Since the output is inverted to a low level signal and the output of the AND gate 16 becomes a low level signal, the above-mentioned idle feed operation is stopped, and the idle feed switch 4
By turning off, the output of the Nant gate 12 becomes a low level signal, and the latch output from the Nant gates 14 and 15 becomes a low level signal (see FIG. 2).

This means that the completion of idle feeding is stored by the latch circuit consisting of the Nant gates 14 and 15.

Next, when the photographer performs a release operation and the switch 3 is turned on, the output of the inverter 19 is turned on.
The exposure control circuit 22 operates, and the film exposure operation is started. After that, when the exposure operation is finished and the exposure control circuit 22 outputs a 71-level signal, the output of the tend gate 37 becomes the I-level signal, the winding circuit 24 is excited, and -frames of film are wound. .

Next, a case will be described in which the lid IIi' is opened and closed when, for example, only three frames of film remain. If the back cover is opened by mistake, the back cover switch 2
is turned on, and a low level signal is generated at the connection point with the pull-up resistor 7.

In addition, since the idle feed switch 4 is also turned on, the pull-up resistor 9
A low level signal is generated at the connection point lζ (see FIG. 2). After that, when you realize that you have opened the back cover by mistake and close it again, the output of the AND gate 16 becomes a high level signal as described above, and the blank feed circuit 17 is activated, for example, 4 frames. The continuous film feeding operation starts. Also, when the back cover is opened, the output of the AND gate 1) is reversed from the low level to the I-REPEL signal, which generates a pulse signal in the one-shot circuit 34, resets the counter 36, and causes the new nine to oscillate. Counting of clock pulses input from the circuit 35 is started (see FIG. 2).

By the way, since the counter 36 outputs a noi level signal from the output terminal Q after a certain period of time (after counting a predetermined number of frames corresponding to the time required to feed four frames), it is possible to carry out normal feeding. In this case, the blank feed ends before the output of the counter 36 becomes a one-level signal, and the output of the AND gate 16 becomes a low level %L/ta:A"
And gate 39 is low level, Nantes gate 2
Since the output of 7 is a Helepel, the Nantes gate 28.
The latch output from 29 remains a low level signal, and the output of OR gate 50 also has a low level signal up to t, so the rewinding circuit 31 is not excited. However, if the film is opened near the end when it is accidentally opened as mentioned above, the output of the counter 36 becomes 01, and the output of the AND gate 39 goes high because the film cannot be fed for 4 frames. level, and the output of the Nant gate 14 is latched at the 1 level, but the output of the Nant gate 27 becomes a low level, and the latched output from the Nant gate 28. It becomes a signal. This energizes the rewind circuit 31 and starts rewinding the film (see FIG. 2).

At the time of the start, the output of the inverter 18 is a low level signal, so the output of the AND gate 16 is a low level signal, and the idle feed circuit 17 does not operate. In other words, the jump forwarding and rewinding operations cannot be performed at the same time.

When the rewinding is completed, the rewinding circuit 31 outputs a high level signal, the output of the NOR gate 53 becomes a low level signal, and the Nant gates ta, ts and 28.29 forming the latch circuit are reset. That is, the latch output is returned to the initial state (low level signal).The rewind circuit 31 is also excited when the 1-null rewind switch 5 is turned on, and the same rewind operation as described above can be performed.

In addition, the above embodiment has a function to display and warn that the jump feed has not been performed normally, and automatically determines whether the jump feed has failed or if the jump feed has failed, and when it is determined that the jump feed has failed. may be displayed, and if it is determined that the feed is overstretched, only rewinding may be performed without displaying the display.

[Correspondence between invention and embodiments]

In this embodiment, the blank feed switch 4, the AND gate 1
) is used as the air transport detection means of the present invention.
．． 15 is a blank feed completion storage means, and a one-shot circuit 34
, the oscillation circuit, the force 'F 7156, and the tend gate 39 correspond to the idle feed abnormality detection means, and the Nantes gates 27 to 29 correspond to the feed instruction means, respectively.

〔Effect of the invention〕

As explained above, according to the present invention, when the film loading toss is closed, the blank feed control device, which automatically feeds the film to a predetermined position, indicates that the blank feed has been completed. A jump feed detection means for detecting the jump feed, a jump feed completion storage means for storing the completion of the jump feed in response to the output of the jump feed detection means, and a jump feed abnormality detection means for detecting that the jump feed is not performed normally. After the completion of the blank feed is stored in the blank feed storage means, when the film loading lid is opened and closed and the film is changed again and the blank feed is performed again, the blank feed abnormality detecting means detects the 9th feed. If a signal indicating an abnormality is output, the film is fed in the opposite direction to the direction of the blank feed. When the film is stretched, the entire film is wound into the film cartridge, so the film is automatically wound without having to rely on the photographer to decide what to do next. be able to.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention, and the second diagram is a timing chart of each circuit shown in FIG. 3. Release switch 4...Jump feed switch 1)...AND gate 12, lji, 15...Syd gate 17...Jump feed circuit inverter 19.22...Exposure control circuit 27~ 29...Nant Gate Sl...Rewind circuit 34 o'clock fist/Wanshi Tatsu) times 1! 35... Oscillation circuit 56... Counter

Claims (2)

[Claims] (1) In a blank feed control device that automatically feeds a film to a predetermined position when a film loading lid is closed, a blank feed detection means for detecting completion of blank feed, and a blank feed detection means for detecting completion of blank feed. Jump feed completion storage means for storing the completion of jump feed in response to the output of the means; Jump feed abnormality detection means for detecting that jump feed has not been performed normally; and Jump feed completion storage means for storing the completion of jump feed in the jump feed storage means. After this has been memorized, when the film loading lid is opened and closed and blank feeding is performed again, if a signal indicating an abnormality in blank feeding is output from the blank feeding abnormality detection means, it is determined that blank feeding has occurred. 1. A blank feed control device for a camera, comprising a feeding instruction means for feeding film in a reverse direction. (2) Resetting the blank feed completion storage means in response to film rewinding. An idle feed control device for a camera according to claim 1, further comprising a reset means.