JPS6259291B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a retrieval method for a roll film reader, and particularly to a method for controlling film braking from high-speed retrieval to film stop.

In the above-mentioned high-speed search, the present invention creates slack in the film of a certain amount or more when detecting a desired frame and suddenly stopping the film, thereby eliminating the slack caused by play between the supply cartridge reel and the shaft. Vibration in the film feeding direction may cause erroneous counting.
The purpose of this is to prevent the possibility that a desired piece will not be retrieved.

First, an example of a microfilm reader to which the present invention is applied will be explained with reference to FIG.

Reference numeral 1 denotes a cartridge containing a supply reel (not shown) in which a film is wound into a roll, 2 a feed-out roller that feeds out the leading end of the film F in the cartridge 1, 3 a feed-out motor that drives roller 2, and 4 a feed-out roller. 2 is a solenoid that moves the film F into contact with the film and a position away from the film; 5 and 6 are film guide rollers; 7 is a take-up reel; and 8 is connected to the rotating shaft 9 of the supply reel to wind the film F into the cartridge 1 10 is a forward feeding motor connected to the rotating shaft 11 of the take-up reel 7 and winds the film F onto the take-up reel 7; 12 is a first motor connected to the supply reel shaft 9;
A brake 13 is a second brake for the take-up reel shaft 11, and various known brakes can be used as these brakes 12 and 13.

The microfilm F in the cartridge 1 is transferred to the feed roller 2 by the drive of the feed motor 3.
The cartridge 1 is pulled out from the cartridge 1 by the holder 1 and fed to the take-up reel 7. When the fed film is automatically wound around the take-up reel 7 rotated by the forward feed motor 10, the solenoid 4 is deactivated, the roller 2 is separated from the film, and the feed motor 3 is stopped. Thereafter, the film F is fed from the cartridge 1 to the take-up reel 7 by the drive of the motor 10 (hereinafter referred to as sequential feeding).

14 is a lamp for illuminating the film; 15 is a condensing lens; 16 is a projection lens for enlarging and projecting the image of the film illuminated by the lamp 14 onto a screen (not shown); m is for each frame a of the film F; A counting mark 17 provided on the side edge is a mark detector that optically detects the mark m on the film illuminated by the lamp 14 and converts it into an electrical signal.

In the above configuration, in order to search for a desired film frame, the film is fed in the forward or reverse direction at high speed, the marks on the film frame are counted by the optical detector 17, and the counted value is determined as the desired frame. When this occurs, brakes are applied to the driving and driven reel shafts simultaneously to stop the film.
One possible method is to slowly move the pieces that have advanced too far back and stop them at the projected position.

However, in the above high-speed search, the second
As shown in the figure, the rotation speed N ₁ of the shaft on the driving side that winds a film with a total number of 3000 frames at high speed is almost constant from 0 frames to 3000 frames, but the rotation of the shaft on the driven side that feeds the film The number N ₂ changes above and below the rotation speed N ₁ of the driving shaft around 1500 frames (midpoint of the film) due to changes in the winding diameter on the reel. Also, the slack of the film when the vehicle suddenly stops from high speed is represented by a curve δ. That is, from the 0th frame to the approximately midpoint of the 1500th frame, it stops while being under tension, and the slack increases significantly from the vicinity of the 1500th frame. In the case of films with different numbers of frames, the number of frames in the vicinity where sag occurs will vary.

On the other hand, when the film slackens, a vibration occurs whose maximum amplitude is the length of the backlash between the shaft hole and shaft of the driven film cartridge reel. If the mark vibrates in the feeding direction and the mark vibrates back and forth on the mark detector, there is a serious problem that erroneous counting occurs and a predetermined piece is not retrieved.

In order to solve the above problems, the present invention has the structure described in the claims. Namely, in this type of search device, when a desired piece is detected, the time chart shown in FIG. A brake signal 24 is issued to apply brakes to the drive shaft and the driven shaft simultaneously. During the braking time, the brake on the driven shaft is temporarily released for a certain period of time _T2 , and then the brake is applied again to prevent the film slack δ from becoming smaller than the maximum amplitude mentioned above. It is characterized by adjusting to prevent erroneous counting.

A specific example will be described below.

FIG. 4 shows a block diagram of a search device that performs the above-mentioned brake control, and the signals input to the processing unit (CPU) 20 such as a microcomputer are the mark signal from the mark detector 17 and the signal from the input device 21. be. From the input device 21, the frame number of the desired image to be searched, the correct frame number in case of an erroneous search, etc. are input. 8 and 10 are the aforementioned reverse feed motor and forward feed motor controlled by the CPU 20, 22 is a forward feed signal sent from the CPU, 23 is also a reverse feed signal, 24 is a brake signal, and 25 is the brake 12 and 13. This is a control circuit that controls the

FIG. 5 illustrates the brake control circuit 25, in which A ₁ to A ₃ and A ₅ to _{A 7} are AND gates, R ₁ and R ₂ are OR gates, I ₁ and I ₂ are inverters, and T ₁ and T ₂ is a timer and P is a flip-flop, which operate as follows.

When a desired frame number to be searched is input to the input device 21, the CPU compares it with the previous search frame number stored and determines whether it is forward or reverse, and rotates the forward feed motor 10 or the reverse feed motor 8. let If it is a forward feed search, the motor 10 will be on the driving side and the motor 8 will be on the driven side.

The film is fed at high speed, the detector 17 detects the mark m, the CPU counts the signal, and when the number matches the input desired frame number, the CPU sends a signal to the flip-flop P of the brake control circuit 25. The brake signal 24 is sent to the terminal S as "1".

The output Q "1" of flip-flop P is sent to AND gate _A1 . Since the forward feed signal 22 "1" is added to the AND gate A ₁ , a signal is output from the OR gate R ₁ and the drive side motor 1 is
The circuit of the second brake 13 for the zero axis 11 is controlled and the brake 13 is applied.

The output "1" of the above flip-flop P is also input to AND gate A ₃ and timer T ₁ , timer T ₁ starts operating, and its output becomes one input of AND gate A ₃ as a signal to the next AND gate A ₅ . send.
While timer T ₁ is operating, the input of timer T ₂ is set to "0" by inverter I ₁ , so timer T ₂ is not operating, so it becomes the other input of AND gate A ₅ ,
Send one input signal from A ₅ to the next A ₆ .

Since the forward feed signal 23 is input to the other input of the AND gate A ₆ , the circuit of the first brake 12 for the shaft 9 of the driven motor 8 is controlled through the OR gate R ₂ , and the circuit of the first brake 12 for the shaft 9 of the driven motor 8 is controlled. Apply at the same time.

When the timer _T1 turns off after a predetermined time _T1 , the timer _T2 starts operating by the inverter _I1 and outputs "1". The "0" inverted by the inverter _I2 is input to one side of the AND gate _A5 , and the output of the AND gate _A5 becomes "0" for the operating time _T2 of the timer _T2 , so the driven brake 12 is turned off. timer
When T ₂ is turned off, "1" is input to AND gate A ₅ and the driven brake 12 is operated again.

That is, the operations shown in the time chart of FIG. 3 and the flow chart of FIG. 6 are performed.

For backward-feeding searches, use the AND gate.
“1” is sent from the CPU to A ₂ and A ₇ as the reverse signal 23.
is input. Since the output of AND gate A ₅ is input to AND gate A ₂ , brake 13
As the driven side, it turns on for the time set by timer _T1 , turns off for the time set by timer _T2 , and then operates again. Since the output Q of the flip-flop P and the reverse feed signal 23 constitute the input of the AND gate _A7 , the output of the AND gate _A7 becomes "1", and the brake 12 becomes the driving side and continues to operate.

Reset signal 3 to terminal R of flip-flop P
The brake operates until 0 is input. The reset signal may be sent in conjunction with the start of the next search operation.

As described above, the present invention operates the brakes on the driving side and the driven side simultaneously when searching the microfilm at high speed and stopping it suddenly, and after T ₁ hour has passed, the brake on the driven side is turned OFF for T ₂ hours and then operates again. By this, sagging of the film when it is stopped is controlled. Therefore, if the amount of sag at the sag curve δ in Fig. 2, where sag begins to occur around, for example, 1500 pieces under tension, is controlled to be larger than the vibration amplitude due to play in the supply cartridge reel, the above search result can be achieved. Mistakes are prevented.

Furthermore, in making the lower limit of the slack greater than the maximum amplitude of vibration due to backlash in the mechanical system that occurs when the film is stopped, the amount of slack is adjusted by the driven side brake control times T ₁ and T ₂ . Therefore, even when using a cartridge reel with a different mechanical backlash or a different type of cartridge reel, it is possible to perform a high-speed search by adjusting the reel to suit each case. Further, in the forward direction feed search and the reverse direction feed search, the inertial systems on the supply side and the winding side may be different, so in that case, the control times T ₁ and T ₂ described above are changed as appropriate.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a microfilm reader printer to which the present invention is applied, FIG. 2 is a graph showing the relationship between the number of frames, the amount of film slack, and the reel shaft rotation speed, and FIG. FIG. 4 is a block diagram of the retrieval device of the present invention, FIG. 5 is a brake control circuit diagram, and FIG. 6 is a flow chart. 1 is the cartridge, 8.10 is the motor, 12.
13 is a brake, 17 is a mark detector, F is a film, and m is a mark.

Claims (1)

[Claims] 1. In a roll film search method in which a desired frame is searched by counting the marks while feeding the roll film, and when the desired frame is found, a brake is applied to stop the film, when the mark of the desired frame is detected, the roll is stopped. A roll film characterized by applying brakes to the take shaft and the supply shaft simultaneously, temporarily releasing the brake on the supply shaft for a certain period of time during the braking, and then applying the brake to the supply shaft again to stop the film. retrieval method.