JPH04120043U - ink paper feeder - Google Patents

Abstract

(57) [Summary] [Purpose] Ink paper (ink ribbon) for thermal transfer printers
In the feeding device, uneven print density in the feeding direction of the receiving paper,
Registration, reduces the occurrence of wrinkles on ink paper,
Enables high quality printing. [Structure] A tension control means is provided for controlling the tension applied to the ink paper to weaken as the amount of current applied to the thermal head increases.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to the ink paper (ink ribbon) feeding device of thermal transfer printers, especially Concerning improvements in tension control of ink paper.

0002

[Conventional technology]

FIG. 2 is a structural explanatory diagram of a printing section of a thermal transfer printer. The printing section 1 includes a thermal head 2 and an ink paper feeding device 3. The ink paper feeding device 3 is an ink paper sending motor for feeding the ink paper 4. 5, an ink paper take-up motor 6, a platen 8 for feeding the image receiving paper 7, and a platen 8 for feeding the image receiving paper 7. It consists of a platen motor 9 that drives a laten 8. For printing, the thermal head 2 presses the ink paper 4 onto the receiver paper 7 on the platen 8. This is done by controlling the amount of current applied to the heating resistor 2a of the thermal head 2 in the Ru.

0003 In a thermal transfer printer with such a structure, the For example, when using 3 or 4 color ink paper, uneven printing density may occur. -For products that print images, the printing position of each color is called registration. The interrelated problems of paper misalignment and wrinkled ink paper are common. It has been known since ancient times.

0004 Conventional thermal transfer printers use an ink paper feed motor to suppress wrinkles. Apply back tension to the ink paper 4 by, for example, applying a reverse voltage to the motor 5. ing.

[0005]

[Problem that the idea aims to solve]

However, adjusting the back tension is delicate, and setting the back tension to a strong Then, when the print density is low, slipping occurs between the image receiving paper 7 and the ink paper 4, causing the ink Print paper 4 no longer advances by the specified amount, resulting in uneven print density and registration problems. tion also worsens. The distance between the ink paper 4 and the image receiving paper 7 depends on the amount of current applied to the thermal head 2. This is because the degree of adhesion is different. Generally, at high temperatures with a large amount of current flowing, a large amount of ink is Because of the transfer, the degree of adhesion between the ink paper 4 and the image receiving paper 7 is high. For this reason, relatively Ink paper 4 can be fed even if a large back tension is applied, but thermal At low temperatures when the amount of electricity supplied to the head 8 is small, the degree of adhesion between the ink paper 4 and the image receiving paper 7 is low. Because it is lower, slipping is more likely to occur.

[0006] This idea was made to solve these problems, and its purpose was to We offer an ink paper feeding device that can reliably feed paper and produce high quality printing. It is to serve.

[0007]

[Means to solve the problem]

In order to solve the above problem, the ink paper feeding device according to this invention uses a thermal head. As the amount of electricity applied to increases, the tension applied to the ink paper is weakened. It is characterized by comprising a tension control means for controlling the tension.

[0008]

[Effect]

Controls the tension applied to the ink paper based on the amount of electricity applied to the thermal head This can reduce print density unevenness in the sub-scanning direction, registration, and ink paper shading. It is possible to suppress the occurrence of warts.

[0009]

【Example】

Hereinafter, embodiments of this invention will be described with reference to the accompanying drawings. FIG. 1 is a circuit diagram of the main part of the printing section according to this invention. The printing unit 1 includes an energization control unit 10 that controls the amount of energization to the thermal head 2, and a template. and a control means 20.

0010 The energization control unit 10 includes a thermal head power source 11, a maximum current limiting resistor 12, It includes a driving transistor 13 and its base resistor 14, and is supplied to a control terminal 15. is supplied to the heating resistor 2a of the thermal head 2 based on the energization amount control signal VA. It is configured to control the current that flows.

[0011] Note that the internal resistance of the thermal head power supply 11 is relatively high, and the power supply to the heating resistor 2a is The voltage value applied to the terminal 2b of the thermal head 2 changes depending on the amount of current applied to it. In this case, the current limiting resistor 12 may not be provided.

0012 The tension control means 20 generates an offset voltage VS. The difference between the raw circuit 21, the offset voltage VS, and the voltage VH applied to the thermal head 2 A comparison amplifier circuit 22 that outputs a voltage corresponding to the voltage, a drive circuit 23, and a positive and negative power supply It consists of +VCC, -VCC, and an ink paper feed motor 5.

[0013] The offset voltage generation circuit 21 calculates and increases the voltage divided by the variable resistor 21a. Low impedance is provided through a voltage follower circuit 21b configured using a width switch or the like. The configuration is such that the output is done on a smartphone.

[0014] The comparison amplifier circuit 22 includes a dual power supply type operational amplifier 22a and various input resistors 22b. ~22d, the output of the drive circuit 23, and the inverting input terminal (-) of the operational amplifier 22a. A feedback resistor 22e is connected between the two. The output VQ of the operational amplifier 22a is connected to an NPN type transistor 23a and a PNP type transistor. The ink cartridge 23b is supplied to the drive circuit 23 connected to the totem pole, and the ink is The configuration is such that the paper feed motor 5 is driven. The ink paper feed motor 5 or the ink paper feed side motor mechanism is connected to one terminal. When a positive voltage is applied to 3a, feeding tension is applied to the ink paper, and a negative voltage is applied to the ink paper. When a polar voltage is applied, back tension is applied, and the voltage is applied depending on the applied voltage. The structure is such that the tension increases.

[0015] Next, the operation of this printing section 1 will be explained. The voltage VH applied to the thermal head 2 is a voltage drop caused by the current limiting resistor 12. Therefore, it decreases according to the current applied to the heating resistor 2a. This voltage VH is divided by the input resistors 22c and 22d, and the operational amplifier 22 The voltage applied to the non-inverting input terminal (+) of a and the voltage applied to the inverting terminal (-) A voltage VQ corresponding to the difference between the It is supplied to the motor 3.

[0016] Here, considering the change in the voltage applied to the thermal head 2, offset voltage If VS is set, the amount of current applied to the thermal head 2 will be reduced and the print on the thermal head 2 will be reduced. When the applied voltage VH is relatively high, a negative voltage is supplied to the ink paper feed motor 3. to apply feeding tension to the ink paper 2 and adjust the amount of current applied to the thermal head 2. When the voltage VH applied to the thermal head 2 is relatively low, the ink paper is not fed out. A positive voltage is supplied to the motor 3 to apply back tension to the ink paper 2. You can get it.

[0017] In this way, depending on the amount of electricity applied to the thermal head 2, the amount of electricity applied to the ink paper 4 is Since the tension is adjusted, the feeding of the ink paper 4 will not stop even if the print density changes. Furthermore, the tension is adjusted according to the degree of adhesion between the ink paper 4 and the image receiving paper 7. The print quality is adjusted to ensure high-quality printing without uneven print density or registration. It can be carried out.

[0018] In this embodiment, the voltage applied to the ink paper is determined based on the voltage VH applied to the thermal head 2. Although the configuration for controlling the applied tension has been explained, it is based on the energization amount control signal VA. The tension may be controlled accordingly. In addition, the number of pulses applied to the thermal head 2 and the duty of the pulses can be changed. In the method of controlling print density using Just configure it. In addition, the tension adjustment of the ink paper 4 is performed using a motor other than the ink paper feed motor 5. This may also be done by a tension adjustment mechanism.

[0019]

[Effect of the idea]

As explained above, the ink paper feeding device according to this invention is capable of passing through the thermal head. The structure controls the tension applied to the ink paper based on the amount of electricity, so the print density can be reduced. The feeding of ink paper does not stop even if the reading speed changes, and the printing in the sub-scanning direction is By suppressing uneven character density, registration, and wrinkles on ink paper, you can achieve high quality. Can print.

[Brief explanation of drawings]

[Fig. 1] Main part circuit diagram of the ink ribbon feeding device according to this invention

[Figure 2] Structure explanatory diagram of the printing section of a thermal transfer printer

[Explanation of symbols] 1...Printing section, 2...Thermal head, 2a...Heating resistor,
3... Ink paper feeding mechanism, 4... Ink paper (ink ribbon), 5... Ink paper sending motor, 6... Ink paper winding motor, 7... Receiving paper, 8... Platen, 9... Platen motor, 10... Energization control section, 20... Tension control means, 21... Offset voltage generation circuit, 22... Comparison amplifier circuit, 23... Drive circuit, VA... Current flow amount control signal, VQ
...Comparison output (ink paper tension control voltage), VS...
Offset voltage.

Continuing from the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location B41J 35/08 7318-2C

Claims (1)

[Scope of utility model registration request] 1. An ink paper feeding device comprising a tension control means for controlling the tension applied to the ink paper to weaken as the amount of current applied to the thermal head increases.