JPS6129273A - Recorder - Google Patents

Abstract

PURPOSE:To prevent the occurrence of the recording irregularity in terms of a facsimile of a thermal head system by extending a conductive period to a recording head at the time of recording a specific dot. CONSTITUTION:Data by block is read out when line memories 1 and 2 are in the readable state and when a line memory 3 is in the writable state. Said memories are switched by a select signal from a select circuit 4, and two-line grouping signals (e) are outputted. A basic signal (f) and a comparison signal (g) are stored in block memories 5 and 6, and parallel signals are outputted from both memories 5 and 6. In terms of the 1st gate circuit 7, a dot corresponding to a previous line signal is compared with that corresponding to a recording picture signal. Then a specific bit of data zero and that of data 1 are extracted in a previous line and recording line, respectively, and outputted to a pulse generator circuit 8, where a pulse (i) wider than normal recording signal width is generated. Finally the recording signal is outputted from the 2nd gate circuit 9.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to printing apparatuses, and particularly to a printing apparatus that uses a thermal head to control density and perform gradation printing.

Conventional configuration and its problems Conventionally, in thermal head facsimile machines, the amount of energy per dot is the same whether recording one dot or continuous dots in the sub-scanning direction. When only one dot is recorded, the density does not increase and the recording becomes thin, uneven recording occurs, and it is very difficult to see, and in some cases, it may not be recorded at all.

OBJECTS OF THE INVENTION An object of the present invention is to provide a recording apparatus that can eliminate recording unevenness that occurs in one-dot recording and perform uniform recording.

Structure of the Invention The recording device of the present invention includes first, second, and third line memories that store image signals for one line, and selects two line memories from among these three line memories to record each line. a selection circuit that divides a line-by-line image signal stored in a memory into blocks and alternately selects and outputs the divided image signals; and first and second block memories that store the image signals that are alternately divided into blocks. and is configured to perform printing by energizing the recording head in accordance with the basic image signal of the basic image signal stored in the first block memory and the comparison image signal stored in the second block memory. At the same time, a gate circuit compares the same position of the basic image signal and the comparison image signal and extracts a specific dot where there is no recording data on the comparison image signal line and there is recording data on the basic image signal line, and an output of this gate circuit. The present invention is characterized in that a correction means is provided for extending the time during which the recording head is energized during recording of the specific dot by a signal, compared to when recording other dots.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of the present invention. (1) to (3) are 1-line memories that store the input image signal (a), and store, read, and read out the image signals in the order of line memories (1), (2), and (3), respectively. Each readout output image signal (b) is repeated line by line.

(C) and (d) are outputted to the select circuit (45).The select circuit (4) outputs the M block signals of N lines and the M block signals of (N+1) lines for each block set in advance. Selects the input two line memory signals, divides them into blocks, switches them alternately, and outputs a two-line collective signal (e). (5) (6)
is a block unit memory and the block memory (5) is the above (
The memory (6) receives the M block signal of the N+1) line.
The signals of M blocks of lines are stored and output as a basic image signal (f) and a comparison image signal (g) to be recorded, respectively. The first gate circuit 1 (7) detects dots that are opposite to each other in the sub-scanning direction between the basic image signal (f) in block units to be recorded and the comparative image signal (g) which is the output of the same block position in the previous line. The dots existing only in the basic image signal are extracted and output to the pulse generating circuit (8). The pulse generation circuit (8) generates a pulse with a width slightly wider than one recording dot set in advance in response to the input signal, and the gate circuit (9) synthesizes it with the basic image signal in the memory (5), and generates a pulse in the sub-scanning direction. On the other hand, the recording signal width of the first appearing dot is widened to make the recording device uniform.

Next, the operation shown in FIG. 1 will be explained in detail with reference to FIGS. 2 and 3. Here, an example will be explained in which the data length of one block is 4 dots, line memories (1), (2), and so on are successively written, and line memory (3) is in the writing state.

(k) in FIG. 2 represents a write clock for the line memory (3). At the timing when the data of line memory (2) is recorded, (β) and (0) are read clocks of line memory (1) and (2), respectively, and are read out in 4-bit units intermittently, and (b) and (Q) Each block of data is read out, and is switched by a select signal (p) by a select circuit (4) to receive a 2-line batch signal (e
) is output. In the figure, n indicates a line position and m indicates a block position, and signals 1n in (b) and 2n in (c) are data at the same block position different by one line in the sub-scanning direction. In the next line, line memory (2) (3
) 62-line batch signal (
When the contents of e) are set to the state of (e-1) in FIG. -1)～(
f-4) and (g-1) to (g-4) parallel signals are output. In the first gate circuit (7), opposing dots ((f-1), (g-1), (f-2) of the previous line signal [comparison picture signal] and the recording picture signal [basic picture signal] are detected.
Comparing (g −2)..., data is "0" in the previous line and data It I I + in the recording line.
A specific dot is extracted and outputted to the pulse generation circuit (8). Here, dot (n-1) is a specific dot,
The pulse generating circuit (8) generates a pulse (i) wider than the normal recording signal width by T''
-1), and the second gate circuit (9) generates the conventional recording signals (f-1) to (f-4) and the pulse generating circuit (
8) Combine outputs (i-1) to (i-4) and record signals (j-1) to (j −
4) Output.

As described in the detailed description of the invention, the recording apparatus of the present invention is configured to execute recording by energizing the recording head according to the basic image signal of the basic image signal and the comparison image signal, and also to A gate circuit that compares the same position of the comparison image signal and extracts a specific dot for which there is no recording data on the comparison image signal line and that has recording data on the basic image signal line; Since a correction means is provided to extend the power supply time to the recording head compared to when recording other dots, the recording energy is increased to increase the recording density when recording one dot in the sub-scanning direction or at the leading end of continuous dots. This makes it possible to realize recording with uniform density without causing recording unevenness as in the conventional method.

[Brief explanation of drawings]

FIG. 1 is a block diagram of essential parts of an embodiment of the recording apparatus of the present invention, FIG. 2 is an explanatory diagram of the 2-line batch signal in FIG.
The figure is an explanatory diagram of a specific dot recording state using a specific example of a signal. (1) (2) (3)... line memory, (4)...
...Select circuit, (5) (6)...Block memory [first and second block memories], (7)...First gate circuit, (8)...Pulse generation circuit, ( 9)
. . . second gate circuit, (e) . . . 2-line batch signal, (f) . . . basic image signal, (g) . . . comparative image signal. (j)... Recording signal agent Yoshihiro Morimoto

Claims (1)

[Claims] 1st, 2nd, and 3rd to accumulate image signals for one line.
The line memory and two of these three line memories are selected, the line-by-line image signal stored in each memory is divided into blocks, and the image signals divided into blocks are alternately selected and output. a select circuit, and a first circuit for accumulating the image signals divided into blocks alternately.
, a second block memory is provided, and the recording head is energized according to the basic image signal of the basic image signal stored in the first block memory and the comparison image signal stored in the second block memory. A gate circuit configured to execute recording and for comparing the same position of the basic image signal and the comparison image signal to extract a specific dot for which there is no recording data on the comparison image signal line and there is recording data on the basic image signal line. and a recording apparatus provided with a correction means for extending the time during which the recording head is energized when recording the specific dot, using the gate circuit output signal, as compared to when recording other dots.