JPS61146575A - Thermal recording feeder - Google Patents

Abstract

PURPOSE:To control a habit-removing mechanism according to the amount of the curl of the paper by detecting the curling amount of a thermal recording paper after being recorded by setting a curl detector between a thermal recording head and the habit-removing mechanism. CONSTITUTION:A curl detector 1, consisting of a reflected light detection-type photo sensor, sends out photo-output (a) whose level is varied with distances to a recording paper passing through a guide plate 5. A habit-removing mechanism 2 consists of a guide roller 21, a habit-removing roller 22, and a solenoid 23 which is driven by drive signals (b) from a control circuit 3 to control the curling amount of the paper after being discharged to a fixed amount. It is controlled such that the farther the distance from the detector 1 to the recording paper 4 is, the longer the time for the roller 22 to press is. The pressing time is controlled to press the roller 22 all the time when separated by the farthest distance, whereas to release the pressing of the roller 22 when accessed to the nearest distance. In the intermediate case, according to the distances, the number of pressing line per given paper feeding line number is controlled by applying a drive signal (b) in a pulse form.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a thermal recording conveyance device having a function of correcting the curl of recording paper used when recording by a thermal recording method.

■Prior art The amount of curl of thermal recording paper changes depending on the amount of printing, temperature and humidity, and the state in which the recording paper is held before recording.

Curling is a problem in conveyance and needs to be corrected, but conventionally there was no device to detect the amount of curl, leading to paper jams.

■Purpose The present invention is intended to solve the above-mentioned problems, and provides a thermal recording conveyance device that detects the amount of curl of thermal recording paper after recording and controls a deformation mechanism according to the amount of curl. The purpose is to provide

■Structure Figure 1 shows the structure of an embodiment of the present invention, in which 1 is a curl amount detector, 2 is a curl removal mechanism, 3 is a control circuit, 4 is a recording paper, 5 is a guide plate, and 6 is a recorder. 7 is a platen roller, 8 is a recording head, 9 is a cutter, 10 is a paper discharge motor, 11 is a paper discharge roller, 21 is a guide roller, 22 is a deforming roller, and 23 is a solenoid.

Here, the curl amount detector 1 is composed of a reflected light detection type optical sensor, and generates a light output a whose level changes depending on the distance from the guide plate 5 to the recording paper.

The deformation mechanism 2 includes a guide roller 21 and a deformation roller 22.
and a solenoid 23, and the solenoid 23 is driven by a drive signal from the control circuit 3.

The platen roller 7 rotated by the recording motor 6 is
The recording paper 4 is conveyed by being pressed by the recording head 8 .

The cutter 9 cuts the recording paper when the trailing edge of the recording reaches the cut position, and the cut recording paper is conveyed and discharged by the guide roller 21 and the paper discharge roller 11 by the paper discharge motor 10 .

The book control circuit 3 applies a drive signal S to the solenoid 23 according to the level of the optical output a of the curl amount detector 1, and controls the amount of curl after paper ejection to be constant.

FIG. 2 is a detailed explanatory diagram showing the curled state of recording paper.

After the recording paper 4 passes through the recording head 8 and is conveyed by a predetermined distance, the recording paper 4 is brought into the states shown in A to C by the guide plates 51 and 52. At this time, the control circuit 3 measures the distance from the curl amount detector 1 to the recording paper 4 using the optical output a.

Here, (a) is when the remaining amount of roll paper is low and the amount of curl is large, (b) is when the remaining amount is sufficient, and (c) is a situation where this does not actually occur, to explain reverse curl. This is what is illustrated. Also, depending on the amount of printing, temperature and humidity, how the recording paper is held, etc.

Mouth, or any situation in between occurs.

FIG. 13 shows the output characteristics of the optical sensor constituting the curl amount detector.

In FIG. 2, if the distance from the curl amount detector 1 to the guide plate 52 is xl, and the distance to the guide plate 51 is x2, then
The X distance should be the distance at which the highest level of output can be obtained.

FIG. 4 is a diagram showing a circuit configuration of an optical sensor constituting the curl amount detector.

A reflected light detection type sensor constituting the curl amount detector 1 irradiates the recording paper with light from a light emitting diode 101.

The reflected light is received by the phototransistor 102, and the collector current changes to change the level of the optical output a. 103
is a current limiting resistor, and 104 is a load resistor.

The optical output a is digitized by the A/D converter 31 in the control circuit 3, and the distance is determined by the control circuit 3 after calculation. The control circuit 3 performs control such that the longer the distance from the curl amount detector 1 to the recording paper 4 is, the longer the time for which the S-removal roller 22 presses the recording paper 4.

The pressing time control method is to always press when the object is farthest away, and always release it when the object is closest. In the intermediate case, the number of pressing lines per predetermined number of paper feed lines is controlled according to the distance.

That is, the drive signal is applied in a pulsed manner.

FIG. 5 shows a timing chart of the optical output a and the drive signal S.

■Effects As explained above, the present invention detects the curl amount of thermal recording paper, drives the curl removing mechanism according to the curl amount, and
It has the advantage that the amount of curl can be corrected.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a detailed explanatory diagram showing the state of curling of recording paper, and FIG. 3 is a diagram showing the output characteristics of the optical sensor that constitutes the curl amount detector. Figure, 4th
This figure shows the circuit configuration of the optical sensor constituting the curl amount detector, and FIG. 5 shows a timing chart of the optical output a and the drive signal b. 1... Curl amount detector, 2... Curl removal mechanism, 3...
・Control circuit, 4... Recording paper, 5... Guide plate, 6.
... Recording motor, 7 ... Platen roller, 8 ...
・Recording head, 9... Cutter, IO... Paper ejection motor, 11... Paper ejection roller, 21... Guide roller,
22... Roller for removing the habit, 23... Solenoid, 31
...A/D converter, 51, 52...guide plate,
101... Light emitting diode, 102... Phototransistor, 103... Current limiting resistor, 104...
·Load resistance. a: optical output, b: drive signal. Figure 1 Figure 3 Figure 5 Figure 6 □ Drama Dinggutan U1. -11

Claims (1)

[Claims] A curl amount detector, a curl removal mechanism that can release the curl removal force,
It comprises a thermal recording head and a control circuit that controls the curl removal mechanism according to the curl amount obtained from the curl amount detector, and the curl amount detector is provided between the thermal recording head and the curl removal mechanism. A thermal recording conveyance device characterized by being installed.