JPS6218459B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for stably winding a film-like medium without applying excessive tension to the film-like medium when unwinding it from one take-up roller and winding it onto the other take-up roller. This relates to a feed mechanism that allows rewinding.

Conventionally, a feed mechanism has been used to feed media such as thin and elongated paper, cloth, or plastic film (hereinafter simply referred to as film media) by unwinding it from one take-up roller and winding it onto the other take-up roller. In the past, it was common to drive only the take-up roller. However, in this conventional feed mechanism, since the one take-up roller rotates the other take-up roller via the film-like medium, a large tension is applied to the film-like medium.
Therefore, there was a drawback that the film-like medium could be stretched or damaged. Further, a brake mechanism is required on the side of the roller to be wound up, and a switching mechanism for forward and reverse rotation is required.

This invention has been made to eliminate the above-mentioned drawbacks, and is designed to apply tension to the film-like medium being wound up and rewound within a range that does not cause the film to sag or break. The present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of an embodiment of the present invention, in which 1 is a film-like medium, 2a and 2b
3 is a take-up roller that winds up the film-like medium 1;
a and 3b are movable rollers arranged between the winding rollers 2a and 2b, 4 is a guide roller, and 5 is a movable roller arranged between the winding rollers 2a and 2b;
is a fixed roller disposed corresponding to the movable rollers 3a and 3b, and the film medium 1 passes through the take-up roller 2a, guide roller 4, movable rollers 3a, 3b, and fixed roller 5 to the take-up roller 2b. It is attached so that it can be wound up. 6 is a lever that rotatably supports the movable rollers 3a and 3b; 7 is a spring that biases the lever 6 in a direction away from the fixed roller 5; 8a, 8b, 8;
c and 8d are guide pulleys that slidably support the lever 6; 9a, 9b and 9c are drive pulleys; 10a and 10b are drive belts;
1 is a motor.

Next, the operation will be explained. First, motor 11
When driven, the take-up rollers 2a and 2b rotate at the same speed via the drive pulley 9c, drive belt 10b, drive pulley 9b, drive belt 10a, and drive pulley 9a. Thereby, for example, the film-like medium 1 is rewound from the take-up roller 2a and taken up by the take-up roller 2b, so that the film-like medium 1 can be fed in the direction of the solid line arrow shown in the figure. At this time, since the take-up roller 2a and the take-up roller 2b are started and stopped at the same time and at the same speed, excessive tension may be applied to the film-like medium 1, or the film-like medium 1 may be stretched or damaged. There isn't. On the other hand, due to the above-described operation, the winding diameter of the winding roller 2a becomes smaller, and the winding diameter of the winding roller 2b increases accordingly. Therefore, the amount of film-like medium 1 that is rewound from take-up roller 2a and the amount of film-like medium 1 that is wound up on take-up roller 2b are different, but if this increases the tension applied to film-like medium 1, , the lever 6 moves against the biasing force of the spring 7, and moves the movable rollers 3a and 3b rotatably supported by the lever 6 closer to the fixed roller 5 to alleviate the increase in tension. Conversely, when the tension applied to the film medium 1 decreases, the lever 6 yields to the biasing force of the spring 7 and moves.
The movable rollers 3a and 3b rotatably supported by the fixed roller 5 are moved away from the fixed roller 5 to alleviate the decrease in tension. Therefore, excessive tension will not be applied to the film-like medium 1 and it will not be stretched or damaged.
On the contrary, it does not sag. Similarly, if the motor 11 is rotated in the opposite direction, the take-up rollers 2a and 2
b also rotates in the opposite direction, so that the film-like medium 1 can be fed in the direction of the dashed arrow shown in the figure. At this time, the unbalance between the amount of winding and the amount of unwinding caused by the change in the winding diameter of the winding rollers 2a and 2b can be resolved by moving the lever 6 to move the movable rollers 3a and 3b to the fixed roller. Since the film is absorbed by moving it closer to or farther away from the film 1, the film medium 1 will not be stretched or damaged due to excessive tension applied to it, and will not sag, as described above. Furthermore, the film-like medium 1 will not be stretched or damaged due to excessive tension when it is started or stopped.

Further, in the above embodiment, since the lever 6 is slidably supported by the guide pulleys 8a, 8b, 8c and 8d, the movable rollers 3a and 3b
can be moved parallel to the feeding direction of the film-like medium 1, which has the advantage that the feeding surface of the film-like medium 1 does not move up and down. This advantage is particularly useful in a multi-item input device that uses, as the film medium 1, an information sheet in which a large number of characters, numbers, symbols, etc. are recorded on a film, for example. Furthermore, in order to make the tension applied to the film medium 1 depend on the biasing force of the spring 7 as described above, it is necessary that the movable rollers 3a and 3b are movable, and for this reason, the film medium 1 is made as thin as possible. It is also desirable to increase the diameter of the take-up rollers 2a and 2b to reduce the number of times.

Furthermore, when the long film-like medium 1 is wound up or rewound, the film-like medium 1 may be biased to the right or left, making it difficult to run smoothly. This is because the clearance between the lever and the guide pulley, which determines the operating state of the lever that pivotally supports each opposing roller, especially both ends of the movable roller, and the spring constant of the spring are slightly different between the left and right sides. This is because the axes of the rollers are not necessarily parallel. For this purpose, the shape of the roller, especially the movable roller, is made to have a bulge in the center as shown in FIG. As a result, the film medium 1
The bias is corrected and a force is applied so that the film always moves straight, so that the film medium 1 can run smoothly. Therefore, alignment of each roller becomes easy.

In the above embodiment, an example was explained in which two movable rollers 3a and 3b were arranged and one fixed roller 5 corresponding thereto was arranged, but the present invention is not limited to this. For example, the movable roller is generally n( n may be 1, 2, 3, . . . ), and the larger the number, the more the difference between the amount of winding and unwinding of the film medium 1 can be absorbed for the same amount of movement of the lever 6. This is because the movable roller acts as a movable pulley. Therefore, there are a predetermined number of fixed rollers (take-up roller,
Depending on the arrangement of fixed rollers and movable rollers, n-
1, n, or n+1). Furthermore, the lever may be one that moves the n movable rollers together; for example, the n movable rollers may be rotatably mounted on a plate that can rotate about a shaft (not shown). Of course, it can also be implemented in the same way.
Further, the shape of the lever can be T-shaped, L-shaped, I-shaped, or any other arbitrary shape. Furthermore, the drive mechanism that drives the take-up rollers 2a and 2b simultaneously and at the same speed preferably obtains the driving force from one motor, and in this case, the means for transmitting the driving force is not limited to belts and pulleys, but also gears. The same can be done by transmitting the information.

As explained in detail above, according to this invention,
Excessive tension is not applied to the film-like medium, and therefore the film-like medium does not stretch or break. Furthermore, the film medium can be made thinner, thereby not only increasing the driving speed, but also eliminating the need for a brake mechanism and a mechanism for forward and reverse rotation, which were conventionally required. In addition, by forming the center of the roller, especially the movable roller, into a bulging shape, alignment of the roller axes becomes easy, which has the advantage that an excellent feed mechanism can be easily obtained at low cost.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a schematic configuration of an embodiment of the present invention, and FIG. 2 is a plan view showing another roller shape. In the figure, 1 is a film medium, 2a, 2b are take-up rollers, 3a, 3b are movable rollers, 4 is a guide roller, 5 is a fixed roller, 6 is a lever, 7 is a spring, 8a, 8b, 8c, 8d are guide pulley,
9a, 9b, 9c are drive pulleys, 10a, 1
0b is a drive roller, and 11 is a motor.

Claims (1)

[Claims] 1. In a feed mechanism for rewinding a film-like medium from one take-up roller to the other take-up roller, an n( n is 1, 2, 3...) movable rollers, a predetermined number of fixed rollers arranged corresponding to the movable rollers,
two levers that integrally support both ends of the n movable rollers, a guide pulley that supports each of the levers so as to be slidable in parallel to the feeding direction of the film medium; A feed mechanism comprising a spring that biases each roller, and a drive means that drives the two take-up rollers at the same speed.