JPS58110269A - Thermal transfer printer - Google Patents

Abstract

PURPOSE:To remove the difference of the density of printing due to the difference of ink being used by detecting the melting point of a thermal transfer tape and varying conduction time to a thermal head by the melting point detected in the thermal transfer printer using the thermal transfer tape. CONSTITUTION:A central processing unit (CPU) 1 obtains the formation of the melting point of ink from a detector 2 detecting the melting point of the transfer tape 3, and sets value changing related to the melting point of ink through data set pulses to a down counter 5 in response to the information. The CPU1 applies signals to the thermal head 4 by dot information determined according to the information of printing and applies heat to the transfer tape 3, but when initial value is subtracted in succession by down counter pulses at the same time as the application of signals and value set reaches zero a latch circuit 6 is reset, the application of heat is completed, and heat quantity added to the transfer tape is brought to quantity through which the optimum density is acquired.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermal transfer printer, and particularly to a thermal transfer printer that has a thermal head and prints by heating a thermal transfer tape.

Conventionally, when printing characters using a thermal transfer printer using a thermal head, the amount of ink on a transfer tape transferred to paper is largely influenced by the melting point of the ink. Even if the same amount of heat is applied using a thermal head, ink with a high melting point will be transferred to paper (2), but only a small amount will be transferred, whereas ink with a low melting point will be transferred to paper (2), a large amount will be transferred. When using C2 transfer tape, the melting point of the ink can be determined according to the amount of heat of the thermal head, but in the case of multi-colored ink, the melting point of C2 cannot be set to the same value due to differences in the pigments of the ink. This is difficult.If the same thermal head performs the transfer using the same amount of heat, the amount transferred to the paper will be different due to the difference in the melting point of the ink, which has the disadvantage that the print density will vary.

Therefore, the present invention aims to eliminate such conventional drawbacks, and provides a thermal transfer printer that can always obtain the same print density and print quality regardless of the melting point of the ink of the transfer tape. purpose.

In order to achieve this objective, the present invention detects the melting point of the transfer tape used for printing (second side printing) and changes the energization time applied to the thermal head according to that information, so that the ink on the transfer tape is in the best condition. A configuration was adopted in which recording was performed on two recording papers.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a schematic configuration of a thermal transfer printer according to the present invention as a block diagram, and in the same figure, reference numeral 1
What is indicated by is a central processing unit (hereinafter referred to as CPU), and this CPU obtains the ink melting point as detection information from the detector 2 that detects the melting point of the transfer tape 3. The CPU 1 sets a value that changes depending on the ink melting point (2) through a set pulse.The CPU 1 also applies a signal to the thermal head 4 from the dot information (2), which is determined according to the printing information, so that the thermal head 4 outputs the dot information. The element corresponding to the applied part is heated, the heat is applied to the transfer tape, and thermal transfer printing is performed on recording paper (not shown).The down counter 5 sets an initial value by the data set pulse of the CPU 1, and The initial value is sequentially subtracted by the counter pulse, and when the set value becomes 0, the latch circuit 6 (reset signal) is generated and the latch circuit is reset. 3) The down counter 5 outputs a heat signal and is reset by the down counter 5 to end the heat.

Note that the melting point is detected, for example, as follows. The detector 2 is provided with several switches 2a,
When the transfer tape case 3' is loaded into the printer,
A detection means is provided which selects one switch and makes it conductive (see FIG. 2). In addition, a protrusion 3'a that turns on the switch 2a of the detector 2 on the case part C of the transfer tape is attached, and the positions of the two protrusions are determined so that the switch of the detector is turned on in accordance with the melting point of the ink. Attach it to the transfer tape case. When the transfer tape is loaded into the printer, one of the switches on the detector is selected and made conductive depending on the position of the protrusion on the transfer tape.

The operation of the thermal transfer printer configured as described above will be explained with reference to FIG.

First, when performing printing, the CPUI detects the ink melting point of the transfer tape based on the detection signal from the detector 2. Depending on the information from this detector, a large value is input when the ink melting point is high (4), and a small value when the melting point is low is input to the down counter 5 in response to the data set pulse shown in Figure 2 (bl). Set.Now, the second
Assume that dot information as shown in Figure (a) appears. At this time, the CPU generates a print start pulse as shown in FIG. 2 (cl), sets the latch circuit 6, and outputs the heat signal shown in FIG. , the CPU generates down count pulses (see Figure 2 (dl)) at regular intervals, and the down counter 5 is subtracted by this, and when the counter value becomes O, that is, T in the figure, the latch is activated. A reset signal is output to the circuit 6, the heat signal is turned off, and printing ends.

That is, in the present invention, the heat signal energized to the thermal head 4, that is, the heating amount T, is T = NX (down count period), and in the case of a transfer tape with a low melting point, a value smaller than this N is on the other hand. In the case of a transfer tape with a high melting point (2 is N), a larger value will be input.The energization time input to the thermal head in this way will be shorter if the transfer tape has a lower melting point. On the other hand, when the melting point is high (the second is long, the printing time can be made variable depending on the melting point of the ink, making it possible to control the amount of ink transferred to the recording paper at a constant level).

As explained above, according to the present invention, the ink melting point of the transfer tape used for printing is detected, and the detected information (
7) The structure is configured so that the ink on the transfer tape is transferred to the recording paper in the best condition by varying the time that the current is applied to the thermal head depending on the temperature, so even if the ink melting point of the transfer tape is different, It has become possible to obtain a thermal transfer printer that can constantly maintain a constant printing quality by changing the amount of heat applied.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of a thermal transfer printer according to the present invention, Fig. 2 is a perspective view illustrating melting point detection, and Fig. 3 (
1A to 1E are timing charts illustrating the operation of FIG. 1; 1...CPU2...Detector 3...Transfer tape ・ ・4
...Thermal head 5...Down counter 6
...Latch circuit.

Claims (1)

[Claims] Heat the thermal transfer tape using a thermal head,
A thermal transfer printer that performs printing by thermal transfer, characterized in that it is provided with a detection means for detecting the melting point of the thermal transfer tape, and prints by varying the energization time to the thermal head according to the detected melting point.