JPH0986003A - Paper feed shift correction device in printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the damage of continuous paper or the shift of a writing start position acompanied by feed shift. SOLUTION: At each time when continuous paper S is fed by one page, a push tractor 3 is reversed by quantity slightly exceeding the shift quantity between the continuous paper S and the push tractor 3 and, subsequently, the push tractor 3 is forwardly rotated by the quantity equal to this reversal quantity and feed shift is corrected each time to perform accurate recording writing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for correcting a continuous paper feeding deviation in a printer.

[0002]

2. Description of the Related Art Generally, in a printer, in order to prevent the slack of the recording paper on the platen, the peripheral speed of the paper discharge roller is set to be slightly higher than the peripheral speed of the paper feed roller so that the recording paper is tensioned. Is given.

However, in the printer in which the continuous paper is sent to the platen by the push tractor, unlike the case of the single-cut paper, the continuous paper is not sandwiched and conveyed. As a result of being easily dragged by the paper ejection roller, not only the normal feed by the push tractor is impaired, but also when recording and writing are performed continuously, the feed deviation between the push tractor and However, there is a problem that the continuous paper is broken by the feed pin that is in contact with the trailing edge of the perforation or that the recording / writing start position is displaced.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to:
It is an object of the present invention to provide a paper feed deviation correction device for a new printer that can accurately convey continuous paper by correcting the deviations at regular intervals.

[0005]

That is, the present invention is, as a paper feed correcting device for achieving such a problem, a tractor for carrying continuous paper on the upper side in the carrying direction with a platen interposed, and a tractor on the lower side. In a printer equipped with a paper discharge roller whose feed speed is slightly higher than that of the continuous paper, the tractor is reversed for each unit number of continuous papers by a distance slightly longer than the amount of deviation from the continuous paper, and A feed deviation correcting means for rotating the tractor in the forward direction by an equal amount is provided.

[0006]

EXAMPLES Examples of the present invention will be described below. The drawings each show an embodiment of the present invention.

First, the paper feed mechanism of a printer to which the present invention is applied will be described with reference to FIG. 4. The platen 1 is sandwiched between the paper feed roller 2 and the push tractor 3 on the upstream side in the paper feed direction. Two sets of discharge roller pairs 4 and 4 that are provided on the lower side and have a peripheral speed slightly higher than the paper feed speed of the push tractor 3 are arranged. It is driven by the feed motor 6, and the pair of paper discharge rollers 4 and 4 are driven by the same paper feed motor 6 via the intermediate gear 5 and the electromagnetic clutch 8 arranged between these gear trains to rotate. It is configured. Reference numeral 9 in the figure indicates a print head.

On the other hand, FIG. 2 shows a feed deviation correction control mechanism added to a part of the printer sequence control mechanism. This feed deviation correction control mechanism 10 includes pulse addition / subtraction means 11 and Setting means 12 and comparing means 13
And a paper feed motor control means 14 and an electromagnetic clutch control means 15.

The pulse addition / subtraction means 11 is a paper feed motor 6
Or the pulse from the rotary encoder attached to the shaft of the paper feed motor 6 is added when the paper feed motor 6 rotates forward and subtracted when the paper feed motor 6 rotates in reverse, and this is input to the comparison means 13. It is configured to be reset by receiving an electromagnetic clutch ON signal from an electromagnetic clutch control means 15 described later.

The setting means 12 sets the number of pulses corresponding to the length of one continuous sheet as n1, and when one continuous sheet S is conveyed as shown in FIG. 1 (b). The gap between the resulting feed pin 3b and the front edge of the perforation a should be δ
1, the clearance between the trailing edge of the perforation a is δ2, and the backlash between the paper feed motor 6 and the belt 3a of the push tractor 3 is ε, the corrected movement amount L of the push tractor is L ≧ The pulse number corresponding to the movement amount L having the relationship of δ1 + δ2 + ε is n2
And the respective setting values n1 and n2 are compared with each other.
3 is configured to be input.

The comparison means 13 includes a count number from the pulse addition / subtraction means 11 and each set value n1 from the setting means 12,
When n2 is compared and the count number matches the set value n1, the coincidence signal is output to the paper feed motor control means 14 and the electromagnetic clutch control means 15.

On the other hand, the paper feed motor control means 14
Is controlled by a signal from the sequence control mechanism 16, and when the coincidence signal from the comparison means 12 is received, the paper feed motor 6 is rotated in the reverse direction to move the push tractor 3 backward by the correction movement amount L, and When the paper feed motor 6 is switched to the normal rotation, the push tractor 3 is controlled to move forward by the same amount as the corrected movement amount L, and when the electromagnetic clutch control means 15 receives the coincidence signal from the comparison means 12. Is configured to turn off the electromagnetic clutch 8 while receiving a correction end signal from the paper feed motor control means 14 to turn on the electromagnetic clutch 8.

Next, the operation of the paper feeding mechanism thus constructed will be described with reference to FIGS. 1 and 3. When the continuous paper S is fed toward the platen 1 by the push tractor 3, the pulse adding / subtracting means 11 counts the pulses output in proportion to the paper feed amount from the paper feed motor by the detection signal from the paper edge detection sensor (not shown). Then, this is input to the comparison means 13 (step a).

When the count number reaches the set value n1 corresponding to the pulse number for the continuous paper S1 page from the setting means 12 (step B), the comparing means 13 outputs this coincidence signal to the electromagnetic clutch control means 15. Then, the electromagnetic clutch 8 is turned off to stop the transmission of the driving force to the paper discharge roller pair 4 (step C), and at the same time, the paper feed motor 6 is switched from the forward rotation to the reverse rotation (step D).

By the way, when the continuous paper S is fed by one page from the initial state of the paper feed shown in FIG. 1A, the peripheral speed of the paper discharge roller pair 4 is constructed to be slightly higher than the peripheral speed of the push tractor. Due to the fact that the continuous paper S is dragged by the paper discharge roller pair 4, as shown in FIG. 1B, a gap δ1 is formed between the paper feed pin 3b of the push tractor 3 and the front edge of the perforation a. Will be able to.

Therefore, when the paper feed motor switched to the reverse rotation rotates from this point by the number of pulses corresponding to the set value n2 (step E), the push tractor 3 is
The clearances δ1, δ2 before and after the perforation a and the corrected movement amount L corresponding to the sum of the amount ε of the backlash interposed between the train wheel and the like, or the amount L slightly larger than this, are retreated, and FIG. As shown in, the paper feed pin 3b is brought into contact with the trailing edge of the perforation a, and the continuous paper S is pulled back by an amount corresponding to the gap δ1.

Therefore, next, the paper feed motor control means 14 switches the paper feed motor 6 to the normal rotation by the coincidence signal with the set value n2 (step F), and the paper feed motor 6 is driven by the number of pulses corresponding to the set value n2. When it is rotated only (step), the push tractor 3 is moved by the previous correction movement amount L.
Only in the paper feeding direction, the paper feeding pin 3b is brought into contact with the front edge of the perforation a to correctly position the continuous paper S of the second page at the writing start position.

When this series of correction operations is completed,
The pulse addition / subtraction means 11 is reset (step
H), and the electromagnetic clutch control means 15 turns on the electromagnetic clutch 8 in response to a signal from the paper feed motor control means 14.
Then, the paper feed motors 6 and 6 and the paper discharge roller pair 4 are connected again (step S1), and the next paper feeding operation is started.

In the above embodiment, the paper feed motor 6 is used.
The electromagnetic clutch 8 for connecting and disconnecting the driving force between the sheet feeding roller pair 4 and the sheet discharging roller pair 4 is interposed, but the train wheel between the sheet feeding motor 6 and the sheet discharging roller pair 4 is corrected. Moving amount L
This electromagnetic clutch can be omitted in the case where there is a backlash that exceeds the above.

Further, in the above description, the correction operation of the feed deviation is performed for each page of the continuous paper S, but when the feed deviation is small, it is described above for each unit of the continuous paper S. You may make it operate.

[0021]

As described above, according to the present invention, a printer provided with a paper discharge roller having a paper feeding speed slightly higher than that of a tractor can be used for each unit number of continuous papers depending on the deviation amount from the continuous paper. Even with a slightly longer distance, the tractor is rotated in the reverse direction, and the deviation amount correction means for rotating the tractor in the normal direction by an amount equal to this reverse rotation amount is provided.Therefore, simply add a new program without adding any new mechanism. It is possible to prevent the continuous paper from being damaged due to the deviation between the continuous paper and the tractor which occurs when the recording and writing are continuously performed, and the deviation of the writing start position.

[Brief description of drawings]

FIG. 1 is an operation explanatory diagram of a paper feeding mechanism that constitutes an embodiment of the present invention.

FIG. 2 is a view showing a feed deviation correcting mechanism of the same paper feeding mechanism.

FIG. 3 is a flowchart showing a feed deviation correcting operation of the same paper feed mechanism.

FIG. 4 is a diagram showing a main part of a printer to which the present invention is applied.

[Explanation of symbols]

 1 Platen 3 Push Tractor 4 Paper Ejection Roller Pair 6 Paper Feed Motor 8 Electromagnetic Clutch 10 Feed Misalignment Correction Control Mechanism

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshikazu Odaka 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Corporation (72) Inventor Takuya Yasue 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Within the corporation

Claims (1)

[Claims] 1. A printer in which a tractor for transporting continuous paper is disposed on the upstream side of the platen in the transport direction, and a discharge roller at a transport speed slightly higher than that of the tractor is disposed on the downstream side of the tractor. For each number of sheets, there is provided a feed deviation correcting means for reversing the tractor by a distance that is slightly longer than the deviation amount from the continuous paper, and then rotating the tractor forward by an amount equal to the reverse rotation amount. Paper feed misalignment correction device for printers that perform printing.