JP3097711B2 - Impact dot printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impact dot printer capable of reducing noise during printing.

[0002]

2. Description of the Related Art A serial impact printer has a problem that noise at the time of printing is greater than other recording methods because recording is performed by causing a printing wire to collide with a recording sheet by electromagnetic energy. For this reason,
As shown in JP-A-144170, impact wires are arranged at an angle θ with respect to a virtual vertical printing position (FIGS. 6A and 6B), and delay circuits 51 to 5 are arranged as shown in FIG.
4, the wires are formed in imaginary vertical positions as shown in FIGS. 6C and 6D by simultaneously supplying the energizing time signals while shifting the energizing time signals, thereby preventing simultaneous driving of the impact wires. It has been proposed to print characters and thereby enable low noise printing.

[0003]

However, it is necessary to complete the printing of the virtual vertical position within the printing cycle, and when giving priority to high-speed printing, it is necessary to take a sufficient delay time. As a result, there is a problem that the impact wires are overlapped at the time of driving, and the noise cannot be sufficiently reduced.

The present invention has been made in view of such a problem, and an object of the present invention is to secure a sufficient delay time even at the time of high-speed printing to simultaneously drive a plurality of wires. An object of the present invention is to provide a serial impact dot printer that can prevent noise and thereby reduce noise.

[0005]

In order to achieve the above object, an impact printer according to the present invention comprises a print head in which a plurality of impact wires are arranged at an angle with respect to a vertical virtual printing position. In the impact printer that prints at the virtual printing position while driving each of the impact wires in a time series at a delay time interval according to the first and the second, the print data is alternately stored for each basic print timing signal. A register, a delay amount register for storing a common delay time corresponding to the tilt angle of the impact wire, and first and second energization time signals alternately generated by the basic print timing signal generated according to a print mode. An energization time generation circuit that operates according to the movement of the print head for each of the delay times from when the first energization time signal is output A first counter for converting the output of the first counter into a drive start signal for each of the impact wires; a first decoding means for converting the output of the first counter into the drive signal for each impact wire; A second counter that operates according to the movement of the head, a second decoding unit that converts the output of the second counter into a drive end signal for each of the impact wires, and a point in time at which the second energization time signal is output. A third counter that operates in accordance with the movement of the print head for each of the delay times, a third decoding unit that converts an output of the third counter into a drive start signal for each of the impact wires, A fourth counter that operates according to the movement of the print head for each of the delay times from the end of the energization time signal, and outputs the output of the fourth counter to the drive end signal of each of the impact wires. Fourth decoding means for conversion, and storage means for storing signals from the first and third decoding means as signals for driving the impact wire, and cleared by signals from the second and fourth decoding means The signal from the third or first decoding means is written in the area in which the impact wires are arranged in the area cleared by the second or fourth decoding means in the arrangement order of the impact wires. .

[0006]

According to the present invention, two types of energization time signals are alternately output at each basic printing timing, and the clearing process of the means for storing data for driving the wire is shifted from the basic printing timing to reduce the wire drive delay time. The basic print timing cycle can be set at the maximum, and a sufficient delay time for correcting the inclination of the wire is secured even when the cycle of the basic print timing is shortened as in the case of high-speed printing.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments. FIG. 3 shows an embodiment of the impact printer of the present invention.
Reference numeral 76 denotes an ink ribbon, and reference numeral 72 denotes a platen. Printing is performed by attaching printing paper (not shown) to the pull tractors 73 and 74. The release lever 75 is provided for switching the paper feed by the tractors 73 and 74 to the paper feed by the frictional force of the platen 72 and a paper feed roller (not shown) when printing on paper such as cut sheet paper.

FIG. 1 shows an embodiment of the present invention. In order to cope with high-speed printing, print data includes a print data N register 1 and a print data H register 2 for each basic print timing signal. Are alternately stored in one of the two. The delay amount register 3 stores the delay amount data of the print timing of each impact wire according to the print mode. The energization time generation circuit 30 uses energization time signals HPW1 and HPW2 that determine the energization time of the print head 76 in synchronization with the basic print timing signal PTS output from an external control circuit (not shown) according to the print mode. The print timing signal PTS is output alternately.
The energization time signal HPW1 is an energization time signal for the data of the print data N register 1, and the energization time signal H
PW2 is an energization time signal for the data in the print data H register 2. Thus, by preparing two types of energization time signals HPW1 and HPW2 for each basic print timing signal, a margin can be provided for erasing data written in the flip-flops 18 to 23, and even during high-speed printing. A sufficient delay time can be provided, and the impact wires can be driven in time series without overlapping.

The 8-bit counter 6 generates a delay time td for delaying the energization start time, sets the value of the delay amount register 3 as a count value by the falling edge of the energization time signal HPW1, and sets a reference clock. Signal C
A subtraction operation is started with LOCK. When the count value becomes 0 as a result of the subtraction, a signal is issued, and the count value is reset by the data of the delay amount register 3 to repeat the count operation. That is, the 8-bit counter 6 outputs a signal at each time set by the delay amount register 3.

The 4-bit counter 10 performs an addition or subtraction operation based on a signal from the control register 4 using a signal from the 8-bit counter 6 as a clock. The output from the 4-bit counter 10 is decoded by the decimal decoder 14, and the nine signals Y0C to
By Y8C, the data of the print data N register 1 is stored in the flip-flops 18 to 20 in a time series for each bit (FS1 to FS9), and the driving of each print wire is started. The signal Y9C of the decimal decoder 14 is a signal that initializes the count value of the 4-bit counter 10 and stops the operation of the 8-bit counter 6 until the falling edge of the energization start signal HPW1 is input.

The 8-bit counter 7 generates a delay time td for delaying the energization end time. The 8-bit counter 7 sets the value of the delay amount register 3 to a count value in response to a rising signal of the energization time signal HPW1, and generates a reference clock signal. CLO
The subtraction operation is started by CK. When the count value of the subtraction result becomes 0, a signal is output, the count value is reset from the delay amount register 3, and the count operation is repeated. That is, 8
The signal from the bit counter 7 is output every time set by the delay amount register 3. 4-bit counter 11
Performs an addition or subtraction operation based on a signal from the control register 4 using a signal from the 8-bit counter 7 as a clock. The signal from the 4-bit counter 11 is decoded by the decimal decoder 15 and the flip-flops 18 to 20 are reset in a time series to drive each print wire by nine signals Y0R to Y8R switched at intervals of the delay time td. To stop. The signal Y9R of the decimal decoder 14
Initializes the count value of the 4-bit counter 11 and stops the operation of the 8-bit counter 7 until the rising edge of the energization start signal HPW1 is input.

The operation in response to the energization start signal HPW2 is exactly the same, and the data of the print data H register 2 is stored in the flip-flops 21 to 23 in a time series for each bit with the delay time td set in the delay register 3. (HS1
HS9), the current is maintained for the energization time defined by the energization start signal HPW2, and reset in time series by nine outputs switched at intervals of the delay time td.

Note that FS1 and HS1 are replaced by FS2 and HS2.
, FS9 and HS9 are logically ORed to become drive signals HD1 to HD9 for wires # 1 to # 9, which are input to the drive circuit shown in FIG. 4 to drive each impact wire. . In FIG. 4, the Zener diode ZD1 and the diode D1 constitute a circuit for absorbing a back electromotive force generated when the transistor Q1 for driving the wire is turned off.

Next, the above-described embodiment will be described with reference to the timing chart of FIG. FIG. 2 illustrates the control in the case where the head inclined to the right by θ with respect to the direction from the back side of the print head to the print paper shown in FIG. 5 is scanned in the direction of the arrow. A signal for performing an addition operation to the 4-bit up / down counters 10 to 13 from a control circuit (not shown) is input to the control register 4, and the initial count value is −
It is 1. When print data is written to the print data N register 1 and the print basic timing signal PTS is input, the energization time generation circuit 30 outputs the energization time signal HPW
Outputs 1. The 8-bit counter 6 starts timing management of the delay time td by the falling edge of the energization time signal HPW1.

When the delay time td elapses, a signal for counting up the 4-bit up / down counter 10 is output from the 8-bit counter 6, and the count value of the 4-bit up / down counter 10 is changed from -1 to 0.
Changes to Thereby, the signal Y from the decimal decoder 14 is output.
0C is output and the data of the wire # 1 stored in the print data N register 1 is stored in the flip-flop 18 by FS1.
Is stored as

When the delay time td elapses from the output of the signal Y0C, the signal is output from the 8-bit counter 6, and the 4-bit up / down counter 10 counts up and the count value becomes 1. As a result, the signal Y1C is output from the decimal decoder 14, and the data of the wire # 2 stored in the print data N register 1 is stored in the flip-flop 19 as FS2.

Hereinafter, data FS3 to FS for wires # 3 to # 9 in a time series manner at intervals of delay time td as described above.
S9 is sequentially stored in the flip-flops 20 to 23. When the delay time td elapses after the data of the wire # 9 is stored as FS9, the count value of the 4-bit up / down counter 10 becomes 9, so that the signal Y9C is output from the decimal decoder 14 and the 8-bit counter 6 The time management of the delay time td is stopped, and the initial value -1 is reset in the 4-bit up / down counter 10.

When the energization time signal HPW1 rises from L to H, the 8-bit counter 7 starts time management of the delay time td. After the elapse of the delay time td, a signal is output from the 8-bit counter 7 and the 4-bit up / down counter 11 is counted up to 0.
Becomes Thereby, the signal Y0 from the decimal decoder 15 is output.
R is output, and the print data FS1 of the wire # 1 stored in the flip-flop 18 is cleared.

Similarly, when the next delay time td elapses,
A signal for counting up the 4-bit up / down counter 11 is output from the 8-bit counter 7, the count value becomes 1, and the print data FS <b> 2 of the wire # 2 of the flip-flop 19 is cleared. Hereinafter, the wires # 3 of the flip-flops 20 to 23 are chronologically sequenced at the delay time td interval.
Print data # 9 to # 9 are cleared.

When the delay time td elapses after the print data FS9 of the wire # 9 has been cleared, the count value of the 4-bit up / down counter 11 becomes 9, the signal Y9C is output from the decimal decoder 15, and the 8-bit counter The timing management of the delay time td at 7 is stopped and
The count value of the bit up / down counter 11 is reset to the initial value of -1.

In the process of clearing the flip-flops 18 to 23 storing the print data of the wires # 1 to # 9 at the previous basic print timing, when the next print basic timing signal PTS is input, the print data is changed to the print data. The energization time signal HPW2 is output to the H register 2, and the print data is sequentially output from the already cleared wires # 1 to # 9 at intervals of the delay time td.
9 is stored.

As described above, by alternately outputting either one of the two types of energization time signals HPW1 and HPW2 for each basic printing timing, the means for storing data for driving the wire is cleared. There is no need to set the process within the basic printing timing, and the delay time can be set to the basic printing timing cycle at the maximum. Even when the cycle of the basic printing timing is shortened as in high-speed printing, the wire # It is possible to secure a delay time sufficient to correct the inclinations of 1 to # 9.

[0023]

As described above, according to the present invention, the clearing step of the means for storing the data for driving the wire by alternately outputting the two kinds of energization time signals for each basic printing timing is described. By shifting from the basic printing timing, the delay time of the wire drive can be set to the basic printing timing cycle at the maximum, and even when the cycle of the basic printing timing becomes short as in high-speed printing,
A delay time sufficient to correct the inclination of the wire can be secured, and the number of simultaneously driven impact wires can be reduced and printing can be performed with low noise even in high-speed printing.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a timing chart showing the operation of the above device.

FIG. 3 is an external view showing an embodiment of a serial impact dot printer according to the present invention.

FIG. 4 is a circuit diagram showing an embodiment of a drive circuit for driving a print head of the printer.

FIG. 5 is a diagram showing an arrangement of wires of a print head of the printer.

FIGS. 6 (a) and 6 (b) are diagrams showing the arrangement of wires of a print head of a conventional printer, and FIGS. 6 (c) and (d) are diagrams each showing a printing result. is there.

FIG. 7 is a diagram illustrating an example of a wire driving method of a conventional serial impact dot printer.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 print data N register 2 print data H register 3 delay amount register 4 control register 6 to 9 8 bit counter 10 to 13 4 bit up / down counter 14 to 17 decimal decoder 18 to 23 flip-flop

Continuation of the front page (56) References JP-A-4-10952 (JP, A) JP-A-2-303862 (JP, A) JP-A-56-111677 (JP, A) JP-A-59-11256 (JP, A) , A) JP-A-56-144170 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41J 2/51 B41J 2/30

Claims (1)

(57) [Claims] 1. A print head in which a plurality of impact wires are arranged so as to be inclined with respect to a vertical virtual printing position, while driving each of said impact wires in a time series at a delay time interval corresponding to said inclination. In an impact printer for printing at a virtual printing position, a first and a second register for alternately storing print data for each basic print timing signal, and a delay for storing a common delay time corresponding to the inclination angle of the impact wire An amount register, an energization time generation circuit that alternately generates first and second energization time signals based on the basic print timing signal generated according to a print mode, and the delay from the time when the first energization time signal is output. A first counter that operates in accordance with the movement of the print head every time, and outputs an output of the first counter to each of the impact wires. First decoding means for converting the printhead signal into a start signal, a second counter which operates in accordance with the movement of the print head for each delay time after the end of the first energization time signal, and an output of the second counter A second decoding means for converting the print head into a drive end signal for each impact wire; and a third counter which operates in accordance with the movement of the print head for each of the delay times from when the second energization time signal is output. And third decoding means for converting the output of the third counter into a drive start signal for each impact wire; and responding to the movement of the print head for each delay time from the end of the second energization time signal. A fourth counter which operates in response to a signal, fourth decoding means for converting the output of the fourth counter into a drive end signal for each impact wire, and signals from the first and third decoding means. Storage means for storing the signal as a signal for driving the impact wire, and cleared by a signal from second and fourth decoding means, wherein the second and fourth decoding means clear the impact wire in the arrangement order of the impact wires. The third or first
An impact dot printer in which signals from the decoding means are written in the order in which the impact wires are arranged.