JPS63295355A - Film drive control device - Google Patents

Abstract

PURPOSE:To make it possible to precisely detect the remaining amount of a film on a supply reel and the trailing end of the film even though the film is intermittently moved, by comparing the time intervals of first and second pulses which are generated in synchronization with the rotation of the supply reel and the travel distance of the film, and variations in the time intervals, with each other so as to control the drive of the film. CONSTITUTION:There are provided a first pulse generating means 8 for generating a pulse in synchronization with the rotation of the shaft of a supply reel 1, and a second pulse generating means 11 for generating a pulse in synchronization with the travel distance of a rolled film 2. Further, the time intervals of the pulses are measured by measuring means so that thus measured time intervals and variations in the time intervals are compared with each other so as to control the drive of the film 2. Further, the measurement of the time intervals by the measuring means is started and interrupted in association with the start and stop of movement of the film 2. Accordingly, even though the film 2 is intermittently moved, the remaining amount of the film and the trailing end of the film may be precisely detected.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a film drive control device that can be applied to rotary cameras, microfilm retrieval devices, etc. The present invention relates to a film drive control device that winds up a film by rotating it and stops it at a predetermined position.

(Prior Art) Conventionally, in film drive control devices that control operations such as winding and rewinding of roll film, accurately detecting the remaining amount of film on the supply reel and the amount of feed is the most important control function. has been done. Incidentally, this is because when the roll film is fed by a drive device such as a motor, the roll film may be fed to the end due to the user's carelessness or erroneous search.

In addition, in the case of a camera for roll film, the last approximately 1.5 m of the film is exposed when the film is taken out of the camera body, so that this portion cannot be used. This makes it necessary to accurately know the amount of film remaining.

Therefore, in response to the above-mentioned needs, various devices have been devised in the past, in which pulses are generated in synchronization with the rotation of the shaft of the supply reel and the moving length of the film, and the time intervals of the pulses are adjusted. There is a device that detects the remaining amount of film and the amount of feed through measurement and comparison.

(Problem to be Solved by the Invention) However, in such a conventional example, if the movement of the film stops while measuring the time interval of pulses, the time interval becomes impossible to measure, and measurement data for this part is lost. There was a problem. On the other hand, when the film is moved continuously, the above problems do not occur, but when the film is moved intermittently, there is a problem in that errors occur in the measured data.

Therefore, the present invention has been made to solve the above-mentioned problems of the conventional example, and its purpose is to prevent the film from being wound around the supply reel even when the film is moved intermittently. An object of the present invention is to provide a film drive control device that can accurately detect the length and end of a film.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a device for winding up a film wound around a supply reel by rotationally driving a take-up reel. first pulse generating means for generating pulses in synchronization with the rotation of the shaft;
a second pulse generating means for generating pulses in synchronization with the moving length of the film; A measuring means for measuring the time intervals of the second pulse generating means, and a control means for controlling the drive of the film by comparing these measured time intervals and changes thereof, The measurement is started and stopped in correspondence with the start and stop of the movement of the film.

(Function) In the present invention having the above configuration, the first pulse generating means generates pulses in synchronization with the rotation of the shaft of the supply reel, and the first pulse generating means generates pulses in synchronization with the moving length of the film. The time interval with the second pulse generating means is measured by each measuring means, and the measured time intervals and changes thereof are compared to control the drive of the film, and further the time interval is measured by the measuring means. Start of film movement.

By starting and stopping in response to stops, the remaining amount of film on the supply reel and the amount of feed out can be detected even when the film is intermittently moving.

(Example) The present invention will be explained below based on the illustrated example. 1st
The figure shows an example in which an embodiment of the film drive control device according to the present invention is applied to a rotary camera.
is a supply reel, and let its diameter be di. 2 is a roll film wound around the supply reel 1; 3 is a capstan for sending out the roll film 2; its diameter is d2. Reference numeral 4 denotes a presser roller paired with the capstan 3, 5 a motor for driving the capstan 3, 6 a take-up reel, 7 a motor for driving the take-up reel 6, and 8 a supply reel l. An encoder as a first pulse generating means attached integrally with the reel shaft, 9, 1
0 are a light emitting element and a light receiving element, respectively, and are arranged at opposing positions with the encoder 8 in between. Reference numeral 11 is an encoder as a second pulse generating means that is integrally attached to the shaft of the capstan 3, and 12 and 13 are a light-emitting element and a light-receiving element, respectively, which are disposed at opposite positions with the encoder 11 in between. By driving the motors 5 and 6, the roll film 2 on the supply reel 1 is wound onto the take-up reel 6.

FIG. 2 is a block diagram of this embodiment, and in the same figure,
14 is a reference clock generation circuit, 15 is an AND circuit, and a counter 16 is a means for measuring clock pulses only when a signal is sent from a control circuit 25 as a control means.
．． 17.

Reference numeral 22.23 denotes a rising edge detection circuit that detects the rising edge of the pulse signal from the light receiving element 10.13, and the output thereof passes through a latch circuit 18.19 and a delay circuit 20.21 connected to the counter 16.17, and is then output to the counter 16.17. It is input to the reset terminal of No. 17. Here, this delay time is set to be shorter than the -oka period of the reference clock. Further, the control circuit 25 controls the drive of the film 2 by comparing the time interval measured by the counter 16.17 and stored in the latch circuit 18.19 and the change thereof. In other words,
The motors 5 and 7 are driven by controlling the motor drive circuit 24 by the control circuit 25.

Control the stop.

In the above configuration, the motor drive circuit 24 of this embodiment is configured to drive the film at "H" and "L" as shown in FIG. 3(b).
When the capstan 3 is rotated by inputting a control signal that stops the film at ``, the encoder 11 also rotates at the same time, and an output waveform as shown in FIG. 3(d) is obtained from the light receiving element 13. From the detection circuit 23, as shown in FIG. 3(e)
The signal shown in is output. Further, the clock input of the counter 17 is connected to a third signal obtained by logically multiplying the reference clock signal (shown in FIG. 3(a)) and the film control signal b (shown in FIG. 3(b)) by the AND circuit 15. The waveform shown in Figure (C) is input.Here, the counter 17 is reset by the first pulse from the rising edge detection circuit 23, and during the next pulse,
The clock signal is counted, and just before being reset by the next pulse, the latch circuit 19 stores the count value and sends it to the control circuit 25. When the film is stopped, there is no clock pulse input, so
A count value proportional to the time interval of the pulses from the encoder 11 is obtained (shown in FIG. 3(f)).

Similarly to the above, the time interval of the pulse signal by the encoder 8 is also measured by the counter 16, stored in the latch circuit 18, and sent to the control circuit 25. As a result, even when the film 2 is fed intermittently, it is possible to accurately feed the film 2, measure the pulse time interval of the encoder 11 of the capstan 3, and use the control circuit 25 to transmit these measurement results to the measured time interval and its changes. By performing a comparison calculation, it is possible to know the feed amount and remaining amount of the film 2, and based on the results, the motor 5 is driven through the motor drive circuit 24.
, 7, the film 2 can be stopped at any desired position or end.

Therefore, in this embodiment, the pulse interval measurement is started and interrupted in correspondence with the movement and stop of the film, so that the pulse time interval interrupted due to the stop of the film can be measured.

In the above embodiment, the rising edge of the second output pulse is detected, but the falling encoder pulse may also be used.
Furthermore, if only the amount of film movement is to be detected, the encoder 8 attached to the supply reel 1 may be attached to the take-up reel 6.

Furthermore, although the above embodiment has been described as an example applied to a rotary camera, it is not necessary to provide the motor 5 in a retrieval device or the like that does not require control of the moving speed of the film.

(Effects of the Invention) The film drive control device according to the present invention has the above configuration and operation, and has the effect of accurately detecting the remaining amount and end of the film even when the film is moved intermittently. .

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view showing an embodiment in which a film drive control device according to the present invention is applied to a rotary camera, FIG. 2 is a block diagram of the same embodiment, and FIG. 3 is an output waveform of each part of FIG. 2. It is a diagram. Explanation of symbols 1... Supply reel 2... Roll film 3
... Capstan 5 ... Motor 6 ... Take-up reel 7 ... Motor 8 ... Encoder (first pulse generation means) 11 ... Encoder (second pulse generation means) 15. ...AND circuit 16.17...Counter (measurement means) 22.23.
...Rise detection circuit 25...Control circuit (control means) Fig. 1 Fig. 2 Fig. 3

Claims (1)

[Claims] A device for winding a film wound around a supply reel by rotationally driving a take-up reel, comprising a first pulse generating means for generating a pulse in synchronization with rotation of a shaft of the supply reel, and a moving length of the film. A second pulse generating means that generates pulses in synchronization with the second pulse generating means, a measuring means that measures the time intervals of these first and second pulse generating means, and comparing these measured time intervals and changes thereof. and a control means for controlling the drive of the film, and the film drive control device is characterized in that the measurement of the time interval by the measuring means is started and interrupted in correspondence with the start and stop of movement of the film. .