JPH0473911B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for driving a paper feed pulse motor of a recording device such as a facsimile machine using a thermal head.

(Prior Art) Usually, the configuration of a heating element of a thermal head can be divided into a plurality of blocks. By the way, if a large number of black bits are to be printed at once, the power supply current for driving the thermal head increases in proportion to the number of black bits, and a larger power supply is required. Therefore, in order to reduce the power supply current, a method has been considered in which the number of black bits to be printed at one time is limited, and one line of heating block groups is divided into a plurality of parts for printing according to the number of black bits.

In conventional devices of this type, when dividing and recording one line of data to be recorded on recording paper, a paper feed pulse motor was driven for the first division and the second division to feed the paper. . As an example of this conventional method, FIGS. 4 and 5 show a method in which a thermal head heating element block group is composed of, for example, seven blocks, and one line of seven blocks is divided into an arbitrary number of divisions for recording. shows.

FIG. 4 is a diagram showing the relationship between the pulse motor drive clock and the dividing method of the heat generating block group according to the conventional method, and FIG. 5 shows the recording position by the heat generating block when recording using the method shown in FIG. FIG.

Note that the division method shown in the figure is an example, and for convenience of explanation, an example is shown in which the second line is divided into three and the third line is divided into seven.

In FIG. 4 and FIG. 5, 1 indicates that the heating element blocks R1 to R7 are grouped together in the first line of recording.
Example of 1-segment recording in which division A1 is recorded once, 2
is the first line of heating element blocks R1 to R3.
Third division B of heating element block R7 between division B1 and second division B2 of heating element blocks R4 to R6
Example of 3-split recording that records in 3 parts, 3
is the 3rd line, and shows an example of 7-division recording in which heating element blocks R1 to R7 are recorded in 7 times, 1st division C1 to 7th division C7, one block each, and 4 and 5 are paper feed A pulse motor driving clock generates two clock pulses per line, with 4 being the 1st pulse and the 1st division, and 5 being the 2nd pulse and the 2nd division. However, paper is not fed after the third division. Reference numeral 6 in FIG. 5 shows a white part that occurs in the conventional dividing method.

Figure 3 shows how the recording position by the heating element block moves as the paper is fed in accordance with the pulse motor driving clock.If the dimension of one heating element block in the paper feeding direction is d, then each time a clock pulse is generated, The recording position moves by d/2. Therefore,
Two clock pulses move the recording position by a distance d corresponding to one heating element block.

(Problem to be solved by the invention) In Figures 4 and 5, the first line 1 and 2
Comparing with line 2, in the 1st line 1, the first division A1 is recorded in the 1st pulse 4 and the paper is fed by d/2, and in the 2nd pulse 5, the 1st pulse has already been recorded. Since one line has been recorded in step 4, the paper continues to be fed by d/2.
In the second line 2, the first division B1 is recorded at the first pulse 4 and the paper is fed by d/2, the second division B2 is recorded at the second pulse 5 and the paper is advanced by d/2, and then the paper is advanced by d/2. The third division B3 is recorded. Here, the recording position of the third division B is already d/2
Since the paper is fed by plus d/2, the recording position is the same as that of the third line 3. In the third line, the first division C1 is recorded at the first pulse 4 and the paper is fed by d/2, and the second division C2 is recorded at the second pulse 5 and the paper is advanced by d/2, and then the second division C1 is recorded and the paper is advanced by d/2 at the second pulse 5. The third division C3 is recorded, and in the same way, the fourth division C4 to the seventh division C7 are recorded without paper feeding.

Here, in the second line 2, the recording position of the second division B2 with respect to the first division B1 and the recording position of the third division B3 with respect to the second division B2 are moved by d/2. ing. Therefore, the position where the first division B1 is recorded is continuous below the first division A1 on the first line, but the recording position of the second division B2 is after the paper has been advanced by one clock pulse. Therefore, the first division A1 and 2 of the first line 1
A gap is created between line 2 and the second division B2. Furthermore, a gap is also created between the bottom of the first division A1 of the first line 1 and the third division B3 of the second line 2. This gap becomes the white spot 6.

Similarly, for the third line 3, the second line 2
The first division B1 and the second division C of the third line 3
2nd line 2, 1st division B1 of 2nd line 2, 3rd division C3 of 3rd line 3, and 2nd division B2 of 2nd line 2 and 4th division C4 of 3rd line 3, A white spot 6 is generated between the fifth division C5 and the sixth division C6. As described above, the conventional method has the drawback of causing white spots on recorded images.

(Means for Solving the Problems) In order to eliminate the above-mentioned drawbacks, the present invention aims to solve the above-mentioned drawbacks by dividing a heating element block group of a thermal head into at least three or more divisions. Among them, only one heating element block belongs to the first division, and the clock pulse for driving the paper feed pulse motor is applied to the first division and the final division among the plurality of division groups. is generated to feed the paper.

(Example) Fig. 1 is a diagram showing the relationship between the pulse motor drive clock and the division method of the heating element block group in an embodiment according to the present invention, and Fig. 2 is a diagram showing the relationship between the pulse motor drive clock and the division method of the heating element block group. FIG. 3 is a diagram showing the position of recording by the heating element block in the case of FIG. Note that the division method shown in the figure is an example.

In Figures 1 and 2, 7 is the first line of recording, 8 is the second line, 9 is the third line, 1
0 and 11 are respectively the 1st and 2nd pulses of the pulse motor drive clock, R1, R2..., R7
are heating element blocks, A1 and A2 are the first and second divisions (final divisions) of the example of two divisions of the first line 7, and B1, B2, and B3 are the second line 8.
In the example of three divisions, the first division, second division, and third division (final division), C1, C2, . . .
C7 is the first of the 7-division example of 9 on the third line.
Division, second division, . . . , seventh division (final division).

(Function) Looking at how each line is divided in FIGS. 1 and 2, the first line 7 is an example of two divisions, and one of the heating element blocks R1 is divided into the first division A1.
The remaining heating element blocks R2 to R7 are defined as the final division A2. This two-division case is the same as a normal paper feeding operation.

The present invention applies to the second line 8, which is an example of three divisions, and one of the heating element blocks R1 is placed in the first division B1.
and heating element blocks R2 to R5 are divided into second division B.
2, and the heating element blocks R6 and R7 are set as the final division B3. The third line 9 is an example of 7 divisions,
7 heating element blocks R1 to R7, one block each, from the first division C1 to the final division C7.
It is divided into times. That is, when the number of divisions in the first line is at least three, the first heating element block R1 is always the first division, and the remaining heating element blocks are arbitrarily divided. The heating element block group is divided in the above manner, and the first pulse 10 of the pulse motor driving clock is applied to the first division A1, B1, C1 of each line, and the second pulse 11 is applied to the final division A2, These two clock pulses generate 2 clock pulses per line.
The paper is fed by d/2 times.

In Figure 2, the first line 7 and the second line 8
Comparing with, in the first line 7,
Record the first division A1 on the first line 10 and press d/
Two sheets are fed, the final division A2 is recorded at the second pulse 11, and the paper is fed by d/2. In the second line 8, the first division B1 is recorded with the first pulse 10, and the position recorded here is a continuous position below the first division A1 of the first line 7. Then, the paper is fed by d/2 and the second division B2 is similarly recorded continuously below the second division A2 on the first line 7. The final division B3 is recorded at the second pulse 11, but since the paper has not been fed before that, the second division B2 is subsequently recorded, and then the paper is fed by d/2. In the third line 9, the first division C1 is recorded with the first pulse 10, but similarly to the second line 8, it is continuously recorded below the first division B1 of the second line 8. Then, the paper is fed by d/2 and the second division C2 is continuously recorded below the second division B2 on the second line 8. From the second division C3 to the final division C7, the paper is not fed and the heating element block is
It is recorded below the division B2 and the final division B3, and the paper is fed by d/2 after the final division C7 is recorded. Therefore, according to this method, the white-out phenomenon does not occur.

(Effects of the Invention) As explained above, according to the present invention, the continuity of recording is maintained between each line when recording on recording paper, so there is an advantage that the phenomenon of white spots on recorded images can be prevented. be.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between the pulse motor drive clock and the division method of the heating element block group in one embodiment of the present invention, and FIG. 2 is a diagram showing the heating elements recorded by the embodiment shown in FIG. 1. Figure 3 is a diagram showing the position of recording by blocks, Figure 3 is a diagram showing how the recording position moves as the paper is fed, and Figure 4 is the relationship between the conventional method of dividing the pulse motor drive clock and the heating element block group. FIG. 5 is a diagram showing the position of recording by the heating element block when recording is performed by the method shown in FIG. 4. 7...1st line, 8...2nd line, 9...
3rd line, 10, 11... Pulse motor drive clock, R1, R2..., R7... Heating element block, A1, B1, C1... 1st division, A2, B
2, C2...second division, B3, C3...third division, C4, C5, C6, C7...fourth, fifth,
6th and 7th division.

Claims (1)

[Claims] 1. In a method of recording on recording paper by variably dividing a group of heating element blocks of a recording paper recording device using a thermal head, only the first heating element block of the group of heating element blocks is treated as the first division, and the remaining dividing the heating element block group into at least two or more divided groups, and driving a paper feed pulse motor in the first divided group and in the final divided group of the plurality of divided groups. Features a paper feed pulse motor drive method.