JP2849113B2 - Recording device and recording method - Google Patents

Description

The present invention relates to a recording apparatus of a dot recording system such as a thermal transfer printer and an ink jet printer, and more particularly to a recording apparatus and a recording method for performing forward recording and backward recording.

[Prior Art] Conventionally, in a dot recording type recording apparatus, recording scanning is generally performed by a recording head capable of recording about 24 dots.

If the number of dots printed in one row is increased to more than 100 in order to increase the printing speed, drive circuits for driving the printing units corresponding to these dots are also required in the number corresponding to the dots. The entire drive circuit becomes large, which leads to an increase in the cost and size of the device. In order to solve this problem, it is conceivable to reduce the number of dots that are simultaneously driven by the drive circuit by dividing the recording head unit into blocks and driving each of the divided recording units in a time-division manner.

FIG. 8A shows the contents of block division of a conventional liquid jet recording head.

In FIG. 8 (A), 128 ejection openings are divided into 16, and recording units 101 to 116 of 16 blocks are arranged in one line, and each recording unit is arranged as shown in FIG. 8 (B). , 8 dots. Such recording units 101 to 116 are time-divisionally driven, and 8 dots are simultaneously recorded.
When the ink is ejected from all ejection ports by moving at a constant speed in the main scanning direction of the recording head, the recording density is 400D
When PI (dot / inch) is set, the interval between the recorded image of the first block and the recorded image of the 16th block is 60
It is close to μm.

Further, the dot interval between adjacent blocks is 4 μm, which corresponds to a size of about one pixel. Therefore, in order to reduce the deviation of the recording dots due to such time-division recording, the recording head is installed obliquely as shown in FIG. 9 (A), and the recording scan is performed, as shown in FIG. 9 (B). Further, it is proposed that only the inclination of the dot row of each block is permitted and each dot row is recorded in one row. FIG. 11 shows the block operation order at this time.

[Problems to be Solved by the Invention] However, in this type of conventional recording apparatus, in order to speed up the recording or to obtain a mirror image, return path recording may be performed. In this case, in the conventional recording apparatus, No.
When the recording head is main-scanned (return-path recording) in the direction indicated by the arrow in FIG. 10A, the same block driving order as in the forward path is performed, so that the deviation of the recorded image is further increased as shown in FIG. 9B. There was a problem to be solved.

Therefore, an object of the present invention is to provide a recording apparatus and a recording apparatus which can solve such a problem and make the image quality of the backward recording similar to that of the forward recording even in a recording apparatus in which the recording head is inclined for time division recording. The idea is to propose a method.

[Means for Solving the Problems] In order to achieve such an object, the present invention provides a printing apparatus which performs printing by moving a printing head relative to a printing medium, and performs time-division driving in block units. A plurality of recording element rows that are linearly provided in the recording head as a plurality of blocks, and are inclined within one row with respect to a direction perpendicular to the relative movement direction, and a memory that stores image data corresponding to a recording position; Designating means for designating a block to be driven among the plurality of blocks during the relative movement of the recording head; and supplying image data to the block designated by the designating means. Reading means for reading from a memory, wherein the specifying means and the reading means include a common counting means, and wherein the specifying means includes the counting means. A block to be driven is specified based on the count value of the stage, the read means sets a read address of the memory based on the count value of the count means, and the read means sets the read address of the count means in the forward path and the return path in the relative movement direction. It is characterized in that the count value is reversed.

Further, in the present invention, the counting means may include a counter for generating an address signal in a predetermined order, and an inverted signal of the output of the counter as one of the forward path or the backward path in the relative movement direction as the count value. And a logic circuit for outputting to the reading means.

Still further, in the invention, it is preferable that the counting means includes an up / down counter that generates an address signal in ascending order and descending order, and that the counting order of the up / down counter is reversed in the forward path and the backward path in the relative movement direction. And

Further, in the present invention, in order to be driven in a time-division manner in units of blocks, the recording element array is linearly divided into a plurality of blocks,
In a recording method of performing recording by moving a recording head disposed so as to be inclined within one line with respect to a direction perpendicular to the relative movement direction with respect to a recording medium, a recording position of image data stored in a memory. During the relative movement of the recording head, to specify a block to be driven among the plurality of blocks based on the count value of the counting means,
In order to supply image data to the designated block, a read address of the corresponding image data from the memory is set based on the count value of the counting means, and the count value of the counting means is determined in the forward movement and the return movement in the relative movement direction. It is characterized in that the values are reversed.

[Operation] In the present invention, since the readout unit of the image data is the unit of the drive block, a common counter means can be used, and the control of the forward path and the return path can be shared, and as a result, the circuit scale is small. Further, with a simple control, it is possible to make the image quality of the backward recording similar to that of the forward recording in a recording apparatus in which the recording head is inclined for time division recording. In addition, since the reading of the image data can be performed in block units in synchronization with the driving of the recording element by the common counting means, high-speed recording can be performed.

Further, in the present invention, the counter value of the counter can be inverted to thereby create the counter value in the reverse order.

Further, in the present invention, the counter direction can be switched by the up / down counter.

Embodiment An embodiment of the present invention will be described below in detail with reference to the drawings.

First, an outline of a bubble jet recording apparatus to which the present invention is specifically applied will be described.

FIG. 2 shows a main configuration of the recording apparatus according to the first embodiment of the present invention. In FIG. 2, reference numeral 901 denotes a carriage on which a recording head is mounted, which is driven to scan in a direction indicated by an arrow S in the figure. Reference numeral 902 denotes a wire to which the carriage 901 is fixed and which is stretched by pulleys 903 provided at both ends of the moving range of the carriage 901.

A motor 904 is connected to one pulley 903 and rotates the pulley 903 to drive the carriage 901 to scan in the S direction in the drawing. Reference numerals 905 and 906 are first and second guard rails extending in the S direction to guide the carriage 901.

Reference numeral 907 denotes a platen roller for regulating the recording surface of the recording medium such as paper or film and transporting the recording medium, and 908 is combined with the platen roller 907 to rotate the platen roller 907 when transporting the recording medium. It is a motor.

Reference numeral 909 denotes a control signal transmission cable, one end of which is attached to the carriage 901, and the other end of which is connected to a control circuit described later, for transmitting image data, control signals, and other signals between the control circuit and the carriage 901. Perform

The cable 909 is in the form of a flexible cable to follow the displacement of the carriage 909.

Next, the principle of discharging a bubble jet will be briefly described with reference to FIG. In FIG. 3, in the state, the meniscus position of the ink exists near the ejection port. A heater is arranged on one surface of the ink discharge passage, and when printing is performed, an electric current is supplied to the heater to heat it. Then
As shown from the state, bubbles in the ink
Is generated, and ink is ejected to the outside by the expansion force of the bubble.

Next, FIG. 1 shows the configuration of a control circuit for performing recording control of the recording head.

In FIG. 1, reference numeral 1 denotes image data for instructing whether or not to perform dot recording corresponding to each dot position, and is input in synchronization with an image clock 2 having a fixed period. VE (video enable) 3 is an information signal for specifying an effective area of an image. A switching signal 4 is a signal for instructing switching between forward recording and backward recording, which is a key point of the present invention.

Reference numeral 5 denotes an address counter that generates read and write addresses of the memory 6 by counting the image clock 2.

The output of the address counter 5 is the EX with the switching signal 4.
After the logical operation of CLUSIVE / OR (exclusive OR), memory 6
The address is entered. Reference numeral 6 denotes a memory serving as a storage unit for temporarily storing image data to be recorded, and is constituted by 8-bit image data per address. In this example, since one block is constituted by eight printing elements (heaters) and time-division driving is performed by 16 blocks, one block of image data is stored in one memory address.

Reference numeral 7 designates the output data of the memory 6 as a data latch pulse 8
Is a latch circuit that holds data at the timing shown in FIG. Reference numeral 9 designates heaters 13-1 to 13 by amplifying the output signal of the latch circuit 7.
This is a segment circuit that generates a drive current for −128, and uses a transistor array.

Numeral 10 denotes a counter as a designating means for designating a heater heating order in units of blocks, which counts the clock signal 14 and designates a block to be heated based on the result of the counting.
As the counter 10, a 4-bit up / down counter capable of counting in ascending order and descending order of a 4-bit output is used, and it is determined by the above-mentioned switching signal 4 whether to count in ascending order or in descending order.

Numeral 12 is a digit (selection) circuit for selectively grounding eight energizing lines connecting the respective heaters in the block in parallel for each block and energizing the heaters in the selected block.
Blocks to be energized are sequentially selected in the order of counting by the 4-bit counter 10.

A decoder 11 decodes the count value of the 4-bit counter 10 and converts it into an instruction signal for the digit circuit 12.

Reference numeral 13 denotes a heater group including 128 heaters, and these heaters are arranged in a row so as to form a fixed angle with respect to the main scanning direction as shown in FIG. 9 (A). Since the various signals 1, 3, 4, 8, and 14 input to the control circuit are often used in the conventional device, detailed description will be omitted.

Next, the recording operation of the circuit shown in FIG. 1 will be described with reference to FIG. 4 and FIG. FIG. 4 shows the operation timing at the time of forward path recording, and FIG. 5 shows the operation timing at the time of backward path recording.

Central processing unit (CP) that controls the overall control of the recording device
When the switching signal 4 of the bit "0" indicating forward recording is generated by U), the gate of the EXCLUSIVE OR circuit 5A opens, and the output of the address counter 5 is directly input to the memory 6. At the same time, the switching signal 4 sets the counter 10 to up-count (count in ascending order). At this time, it is assumed that the image data for the 128 heaters 13-1 to 13-128 is sequentially stored in the memory 6, for example, the image data of the first block is an address "OOH".

Both the address counter 5 and the counter 10 start counting at the same time in order of “0”, “1” (decimal number)... When the count value is "0", the circuits of the heaters 13-1 to 13-8 in the first block are turned on by the digit circuit 12, and the image stored in the address "OOH" of the memory 6 is stored. Data, that is, heaters 13-1 to 13
The image data indicating whether or not to energize −8 is output to the segment circuit 9. In the segment circuit 9, a drive current corresponding to the image data is supplied to the first to eighth heaters in the first block to heat a predetermined heater and perform dot recording. Hereinafter, each time the count values of the address counters 5 and 10 become "1""2" (decimal number) ...
The heater in the second block and the heater in the third block are correspondingly heated.

When the dot recording for all the rows is completed, the 4-bit counter 10 is reset. When the dot recording for two columns is completed, the content stored in the memory 6 is updated to image data for the next two columns, and recording is performed in the same procedure as described above.

Next, when the switching signal is set to bit "1" by the CPU at the time of the return path recording, the output of the address counter 5 is inverted by the next-stage EXCLUSIVE OR circuit 5A, and
Is input to For example, the output value of the address counter “0”
When (decimal) is inverted, the input value of the memory becomes "31" (decimal). At the same time, the counter 10 is selected to count down. It is assumed that two rows of dot data for return path printing are stored in the memory 6 at addresses “OOH” to “1FH” corresponding to the positions of the first to sixteenth blocks.

The counter 10 starts counting from "15" (decimal number). Therefore, the heater of the 16th block can be energized, and the segment circuit 9 has the address “1FH” of the memory 6.
Is output. next,
By updating the count value of the counter 5.10, the image data at the address “1EH” of the memory 6 is output to the segment circuit 9.
When the image data is being output to the segment circuit 9, the digit 15 of the digit circuit 12 is turned on,
The heater of the block can be energized, and a predetermined heater is heated based on the image data.

As described above, time-division printing is performed on a plurality of printing elements (heaters) arranged in a line in a block order opposite to the forward printing, and the printing result is shown in FIG. 9 (B). Like the image shown, the dot images for each block are arranged in one line as in the case of forward printing.

 In addition to the first embodiment of the present invention, the following application examples are conceivable.

1) In the first embodiment, separate counters 10 and 5 are used for the digit circuit 12 and the memory 6, respectively. However, it is possible to use one counter for common use.
As shown in the figure, the lower 4 bits of the EXCLUSIVE OR circuit 5A are input to the decoder 11. As an advantage of this example, it is possible to reduce the size and cost of equipment by reducing the number of circuits.

A disadvantage is that, although not shown, the extension of functions such as adding a preset function to the counter 10 of FIG. 1 to freely set a start position for driving a digit is limited. The first embodiment and the second embodiment may be selectively used as desired.

2) The second embodiment shows an example in which an image is recorded only in black. However, when the present invention is applied to a color recording apparatus, the following advantages are obtained. That is, since there are a plurality of recording units for each color, a memory for temporarily storing image data is provided in order to correct a time shift of color recording for each color. By using this memory and reversing the reading order of the image data in the forward path and the return path, the memory can be saved. In this case, as shown in FIG. 7, a 15 (5.times.3) bit address counter 5 'is prepared, and an EXCLUSIVE OR for performing an exclusive OR operation of the lower 5 bits and the switching signal in the address space. An address is input to the memory 6 'via the circuit 5A, and the upper 10 bits are directly input to the memory 6'.

[Effects of the Invention] As described above, according to the present invention, the readout unit of the image data is the unit of the drive block,
A common counting means can be used, and the control of the forward path and the return path can be shared. As a result, the recording head is tilted for time division recording with a small circuit scale and simple control. In the recording apparatus, it is possible to make the image quality of the backward recording similar to that of the forward recording. Further, the reading of image data can be performed in block units in synchronization with the driving of the recording element by the common counting means, so that high-speed recording can be performed.

Further, in the present invention, the counter value of the counter can be inverted to thereby create the counter value in the reverse order.

Further, in the present invention, the counter direction can be switched by the up / down counter.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration of a first embodiment of the present invention, FIG. 2 is a cross-sectional view showing a main configuration of a recording apparatus of the first embodiment of the present invention, and FIG. 3 is a first embodiment of the present invention. FIG. 4 is a timing chart showing an operation timing of forward printing according to the first embodiment of the present invention, and FIG. 5 is a timing chart showing an operation timing of backward printing according to the first embodiment of the present invention. FIG. 6 is a block diagram showing a circuit configuration of a second embodiment of the present invention, FIG. 7 is a block diagram showing a circuit configuration of a third embodiment of the present invention, and FIG. FIG. 8 (B) is a plan view showing the appearance of a recording section of a conventional example, FIG. 8 (C) is an explanatory view showing a recording example of a conventional example, and FIG. 9 (A). FIG. 9B is an explanatory view showing a forward print direction and a tilt angle of a print head in a conventional example, and FIG. FIG. 10 (A) is an explanatory view showing a recording example of the backward path recording in the conventional example, and FIG. 10 (B) is an explanatory view showing the inclination angle of the recording head of the conventional example. FIG. 11 is a timing chart showing operation timing of a conventional example. 2 ... image clock, 4 ... switching signal, 5 ... address counter, 6 ... memory, 9 ... segment circuit, 12 ... digit circuit, 13-1 to 13-128 ... heater.

Claims (4)

(57) [Claims] 1. A printing apparatus for printing by moving a print head relative to a print medium, wherein the print head is linearly provided as a plurality of blocks so as to be driven in a time-division manner in block units. A printing element row inclined within one row with respect to a direction perpendicular to the direction, a memory storing image data corresponding to a printing position, and a block to be driven among the plurality of blocks during relative movement of the printing head. Specifying means for specifying, and reading means for reading corresponding image data from the memory in block units to supply image data to a block specified by the specifying means, wherein the specifying means and the reading means Includes common counting means, and the specifying means specifies a block to be driven based on the count value of the counting means, Reading means recording apparatus wherein the based on the count value of the count means sets the read address of the memory, to reverse the count value of said counting means in forward and return direction of the relative movement. A counter for generating an address signal in a predetermined order; and an inversion signal of an output of the counter as the count value in one of a forward path and a return path in the relative movement direction. 2. A recording apparatus according to claim 1, further comprising a logic circuit for outputting the data to said reading means. 3. The counting means includes an up / down counter for generating an address signal in ascending order and descending order, wherein the counting order of the up / down counter is reversed in the forward path and the backward path in the relative movement direction. The recording device according to claim 1. 4. A recording device comprising a plurality of recording element arrays arranged linearly so as to be inclined within one line with respect to a direction perpendicular to the relative movement direction so as to be driven in a time-division manner in block units. In a recording method for performing recording by moving a head relative to a recording medium, image data stored in a memory is associated with a recording position, and a block to be driven among the plurality of blocks during the relative movement of the recording head Is set based on the count value of the counting means, and in order to supply image data to the specified block, a read address of the memory of the corresponding image data is set based on the count value of the counting means, A recording method, wherein the count value of the counting means is reversed in the forward and backward directions.