JPS628954A - Strip material traveling apparatus - Google Patents

Abstract

PURPOSE:To maintain the loosening of strip material within specific range between a pair of rollers thus to achieve smooth traveling by controlling such that the difference of the number of total pulses to be inputted to two pulse motors for driving a pair of rollers will be within specific range at anytime. CONSTITUTION:At start of travel of strip material 8, the pulse control section 7 will start driving of respective pulse motor 3, 4 simultaneously while the period of pulse to be fed to the pulse motor 3 is made shorter by (alpha)% than that of pulse to be fed to the pulse motor 4 at anytime thus to drive such that the strip material 8 is loosened slightly between said rollers 1, 2. In order to confine the loosening within specific range, the pulse number control section 7 will monitor the total number of pulse fed from the pulse counters 5, 6 to the pulse motors 3, 4 thus to maintain the difference of total number of pulse between two constant levels at anytime. Consequently, smooth travel of strip material 8 can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for running a strip of material between two or more rollers driven by a pulse motor.

[Conventional technology]

Conventionally, in devices that transport strip materials such as paper or film between two or more rollers driven by pulse motors, it is necessary to make the travel distance of the strip material by two adjacent rollers as equal as possible. Therefore, efforts have been made to improve the accuracy of the diameter of the two rollers, to improve the accuracy of the frequency of pulses input to the pulse motor that drives each roller, or to increase the torque of the pulse motor.

[Problem that the invention seeks to solve]

In the above-mentioned conventional strip material traveling device that runs the strip material between rollers, even if the frequency accuracy of the pulses input to the pulse motors that drive adjacent rollers is improved, the accuracy error in the diameter of both rollers will exceed a certain level. If the friction coefficient of both rollers is large, or if there is a difference in the friction coefficient of both rollers, even if you input enough pulses to the pulse motor to theoretically obtain the same travel distance, an error will occur in the travel distance by both rollers, and this will cause an error. Errors accumulate, so if the distance traveled by the rear roller in the running direction of the strip material is greater than the distance traveled by the front roller, the strip material will slacken more than necessary between both rollers. In the opposite case, the necessary slack is lost, and especially when the torque of the pulse motor that drives the front roller is small, there are drawbacks such as the pulse motor stepping out.

[Means for solving problems]

The strip material traveling device of the present invention includes a pulse motor that drives each roller, a pulse counter that counts the number of pulses input to each pulse motor, and controls input pulses while monitoring the count values of these pulse counters. Of the two adjacent rollers, the difference between the total number of pulses input to the pulse motor of the rear roller in the running direction of the strip material and the total number of pulses input to the pulse motor of the front roller is the first It has a control section that temporarily stops the pulse motor of the rear roller when the set value is reached, and starts driving the pulse motor of the rear roller when the value falls below the second set value after stopping.

Therefore, even if there is an accuracy error in the roller diameter and a difference in the friction coefficient of the rollers, the slack of the strip material between both rollers is the first.
This is maintained within the range determined by the second set value, so that smooth running of the strip material is achieved, and the torque of the tapal motor is small and the motor does not step out.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the strip material traveling device of the present invention.

The strip material traveling device of this embodiment includes two pulse motors 8, 4, two rollers 1.2 of equal diameter driven by the pulse motors 8.4, and an input to the pulse motors 8, 4, respectively. It consists of a pulse number counter 5.6 that counts the number of pulses generated, and a pulse control section 7 that controls the pulses input to the pulse motor 8.4 while monitoring the count value of the pulse number counter 5.6.

In this embodiment, when an equal number of pulses are input to the two pulse motors 8, 4, the traveling distance of the strip material 8 sent by both rollers 8.4 is equal.

In order to realize smooth running of the strip material, the pulse control section 7 further performs control as follows.

The pulse control unit 7 simultaneously starts driving the pulse motor 8.4 when the IJ material 8 starts running, and the period of the pulses given to the pulse motor 8 is always αx shorter than the period of the pulses given to the pulse motor 4. Thus, the strip material 8 is driven so that it is slightly loosened between both rollers. However, since this slack accumulates, the slack in the strip material 8 between both rollers 1.2 gradually increases. Therefore, in order to keep the slack of the object between both rollers 1.2 within a certain range, the pulse number controller 7 controls the pulse motor 8.
Monitor the total number of pulses input to 4 and 1 counter 5.6
When the difference between the count values of C! and C! reaches a certain value C1, the pulse input to the pulse motor 8 is temporarily stopped, and the difference becomes a certain value C! (When the value becomes less than <C,>, input of pulses to the pulse motor 8 is started again.The period of the pulses at this time is still a lot shorter than the period of the pulses input to the pulse motor 4.

Through such control, the difference in the total number of pulses input to the pulse motors 8, 4 is always kept below C1 and above C1, and the slack of the strip material 8 between the rollers 1.2 is kept at C1, C!
Therefore, smooth running of the strip material 80 is realized, and the torque of the pulse motor 8.4 can also be small.

In this embodiment, when an equal number of pulses are input to the two pulse motors 8.4, the traveling distance of the strip jjA' 8 sent by the p-ra 1, 2 driven by both the pulse motors 8, 4 is are assumed to be equal, but if the travel distances of the objects are different, the total number of pulses input to either pulse motor should be adjusted to match the pulses input to the other pulse motor so that the travel distances of the objects are equal. The same control method can be applied if converted using

Further, in the case where there are eight or more rollers driven by a pulse motor, by applying the above control method to two adjacent rollers, smooth running of the object can be realized as a whole of the apparatus.

〔Effect of the invention〕

As explained above, the present invention inputs pulses with a slightly shorter period to the pulse motor at the rear with respect to the traveling direction of the object than the pulse motor at the front, and monitors the total number of pulses input to the pulse motor. By controlling the difference in the total number of pulses input to two adjacent pulse motors to always be within a certain range, even if there is an accuracy error in the roller diameter or a difference in the friction coefficient of the rollers, the difference between the two rollers can be maintained. The slack of the strip is maintained within a certain range (C), allowing smooth running of the strip material, and also has the effect of preventing the pulse motor from adjusting even if the torque is small.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the strip material traveling device of the present invention. 1.2・・・・・・・・・Laura. 8.4・・・・・・・・・Pulse motor. 5.6.......pulse number kunta. 7...Pulse control section *8...
...Strip material.

Claims (1)

[Claims] A strip material traveling device that runs a strip material between two or more rollers, comprising a pulse motor that drives each roller, a pulse counter that counts the number of pulses input to each pulse motor, and a pulse counter that counts the number of pulses input to each pulse motor. While monitoring the count value of the counter, the input pulses are controlled, and the total number of pulses input to the pulse motor of the rear roller in the running direction of the strip material and the pulses of the front roller are calculated. When the difference in the total number of pulses input to the motor exceeds the first set value, the pulse motor of the rear roller is temporarily stopped, and when the difference becomes less than the second set value after stopping, the pulse motor of the rear roller is stopped. A strip material traveling device having a control unit that starts driving.