JPH07267486A - Film conveying device - Google Patents

Abstract

PURPOSE:To prevent excessive tension from being applied to a film by detecting the end of the film, stopping the conveying action, sliding the film not stopped on a friction plate, and regulating torque when the film is extracted from a cartridge and conveyed. CONSTITUTION:A film 2 is extracted from a cartridge 1 and conveyed to an exposure section by a driving roller 6 and a pressing roller 7. When the last frame 2A of the film 2 is not stopped at the exposure section, the end perforation 2a of the film 2 is detected by a detecting means 14. A motor M is stopped by a roller control means 15 based on this detection signal, and the driving roller 6 is stopped. When the film 2 is not stopped and it is wholly extracted from the cartridge 1, a main pulley 9 is slid on the friction plate 13e of a torque regulating means 13 as the torque of the driving roller 6 is increased. Excessive tension is prevented from being applied to the film 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a film-conveying device with a cartridge.

[0002]

2. Description of the Related Art Generally, a film transport device is constructed so that a drive roller and a pressure roller are used to press the film, and the rotation operation of these rollers pulls out the film from the cartridge to transfer the film. When pulled out, the film transport operation is temporarily stopped and then rewound.

However, in the conventional film transport apparatus, when the film is completely pulled out from the cartridge and the rotation of the pressure roller is stopped, the stop state of the pressure roller is detected by the optical sensor, and the rotation of the drive roller is detected by the detection signal. Was trying to stop. Therefore, there is a time lag between the time when the film is completely pulled out from the cartridge and the time when the drive roller is stopped. There was a problem with roller scratches and roller marks.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to prevent the film from coming off the spool and the film from being scratched by rollers. It is to provide a film transport device capable of performing the above.

[0005]

SUMMARY OF THE INVENTION A film transporting device of the present invention is a film transporting device for pulling out a film stored in a cartridge wound on a spool and transporting the film along a transport path by a motor. Conveying means including a driving roller and a pressure roller that are rotationally driven, a detecting means that detects end perforation of the film drawn out from the cartridge, and a roller that receives the detection signal of the detecting means and stops the driving roller. It is characterized by comprising a control means and a torque control means for restricting the drive roller, which is rotationally driven by the motor, so as not to apply a torque larger than a predetermined value.

[0006]

According to the film transport apparatus of the present invention, when the end perforation of the film is pulled out from the cartridge, the end perforation is detected by the detecting means, and the roller control means receives the detection signal of the detecting means. The drive roller is stopped and the film transport operation is stopped.

If the drive roller does not stop due to a control error of the roller control means or the like, the torque of the drive roller can be regulated by the torque regulation means to protect the film. That is, when all the film is pulled out from the cartridge, the film does not move in the transport direction any more, and the torque of the roller shaft of the drive roller increases due to the frictional resistance between the film and the drive roller. It is possible to prevent an excessive tension from being applied to the film due to the operation of the torque restriction means, and to prevent the film from being scratched by a roller or the like.

[0008]

EXAMPLE A film transporting apparatus transports a film (negative film) 2 drawn out from a cartridge 1 along a transporting path 3 to an exposure section for performing an exposure process, and rewinds the processed film 2 into the cartridge 1 again. (Fig. 1).

The film 2 is stored in the cartridge 1 in a state in which the film 2 is wound around a spool 4 and the end of the film 2 is engaged with the spool 4.

The transporting means 5 for transporting the film 2 is formed by arranging a drive roller 6 and a pressure roller 7 with the transport path 3 interposed therebetween. The drive roller 6 is rotated by the motor M. That is, the drive shaft 8 of the motor M
The belt 11 is stretched between the main drive pulley 9 mounted on the drive roller 6 and the driven pulley 10 fixed to the roller shaft 6a of the drive roller 6, and the drive roller 6 is rotated by the rotation of the drive shaft 8. (Figure 1).

The pressure roller 7 is a pressing member 12 such as a spring.
The press roller 7 is elastically urged to be elastically contacted with the drive roller 6, and when the drive roller 6 rotates, the press roller 7 is driven to convey the film 2 while pressing it (FIG. 2). ).

Numeral 13 is a torque regulating means for preventing the roller shaft 6a of the drive roller 6 from generating torque of a predetermined value or more. 13a is a torque control means 1
3, the large diameter portion 13b is formed at the base end portion of the regulation shaft 13a, and the large diameter portion 13b is the motor M.
It is coaxial with the drive shaft 8 and is fixed by a fixing screw 13c.

A pair of friction plates 13e having a shaft insertion hole 13d and a driving pulley 9 having a shaft insertion hole 9a are loosely fitted to the restriction shaft 13a, and the driving pulley 9 is sandwiched by a pair of friction plates 13e. Further, a retaining collar 13g is fixed to the tip of the regulating shaft 13a (Fig. 4).

A compression coil spring 13h is arranged between one friction plate 13e and the retaining collar 13g. The compression coil spring 13h presses the driving pulley 9 against the friction plate 13e. There is. The spring force of the compression coil spring 13h causes the drive shaft 8 of the motor M to move when the film 2 is conveyed.
Can be directly transmitted to the drive pulley 9 by the friction plate 13e, and when the film 2 is completely pulled out from the cartridge 1, friction is applied so that excessive tension is not applied to the film 2 between the cartridge 1 and the driving roller 6. The drive pulley 9 is set so that it can slide with respect to the plate 13e.

Reference numeral 14 is a detection means, which is the cartridge 1.
It detects the end perforation 2a of the film 2 drawn out from the film, and is arranged between the conveying means 5 and the cartridge 1 (FIG. 1). Detection means 14
The detection position of the end perforation 2a is set so that the end perforation 2a can be detected just before the film 2 is completely pulled out from the cartridge 1 or when the film 2 is completely pulled out from the cartridge 1.

Reference numeral 15 is a roller control means for receiving the detection signal from the detection means 14 and stopping the drive roller (FIG. 1).

Next, the operation of the film transport device constructed as described above will be described. (1) First, the film 2 contained in the cartridge 1 is drawn out by the carrying means 5 and is carried to the exposure section for printing exposure.

(2) Next, when the final frame 2A of the film 2 is not stopped at the exposure portion, the detection means 14 detects the end perforation 2a of the film 2 and receives the detection signal of the detection means 14. The roller control unit 15 stops the rotation of the drive shaft 6 of the motor M to stop the rotation of the drive roller 6.

(3) Further, when the film 2 is not stopped by the detection signal of the detection means 14 due to a control error of the roller control means 15 or the like, a torque harmful to the film 2 is generated in the drive roller 6. This is prevented by the torque control means 13. That is, when the film 2 is completely withdrawn from the cartridge 1 and the film 2 cannot be conveyed, the torque of the driving roller 6 increases due to the friction between the film 2 and the driving roller 6, and the driving pulley 9 causes the torque regulating means 13 to operate. Start sliding on the friction plate 13e. As a result, it is possible to prevent excessive tension from being applied to the film 2 and the film 2 from being detached from the cartridge 1, and to prevent the film 2 from being scratched by a roller or a roller mark.

(4) After the film 2 is completely pulled out from the cartridge 1 in this way, the drive roller 6
And rewind the film 2 into the cartridge 1 again.

In this embodiment, the film transporting device is applied to a photo printing device, but it is needless to say that the film transporting device is not limited to this, and can be applied to a photo developing device, for example.

[0022]

As is clear from the above description, the film permeation operation can be stopped by detecting the end perforation by the detecting means, and the driving is performed by the control error of the roller controlling means also by the detection signal. When the roller does not stop, it is possible to prevent excessive tension from being applied to the film or scratches on the film due to the torque regulating means.

As described above, by providing the double safety device, the accident that the film comes off the cartridge can be surely prevented, and the film is free from roller scratches and roller marks.

[0024]

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a film transport device of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view showing a state in which the end perforations of the film are pulled out in the example.

FIG. 4 is a cross-sectional view of the torque restriction means of the same embodiment.

[Explanation of symbols]

 1 Cartridge 2 Film 2a End Perforation 3 Conveying Path 4 Spool 5 Conveying Means 6 Drive Roller 7 Crimping Roller M Motor 13 Torque Limiting Means 14 Detecting Means 15 Roller Control Means

Claims (1)

[Claims] 1. A film transporting device for pulling out a film contained in a cartridge wound on a spool and transporting the film along a transport path, comprising a drive roller and a pressure roller which are rotationally driven by a motor. Transporting means, detecting means for detecting the end perforation of the film pulled out from the cartridge, roller control means for stopping the drive roller upon receiving a detection signal of the detecting means, and rotation driving by the motor. A film transporting device comprising: a torque regulating unit that regulates a drive roller so that a torque not exceeding a predetermined value is applied.