JPS6152792B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called serial type dot printer in which a print head moves relative to a platen in the space direction, and is intended to realize an increase in printing speed.

FIG. 1 is a plan view schematically showing a serial printer, and FIG. 2 is a front perspective view of a print head. A printing paper 2 is wound around the platen 1, and a carrier 6 on which a printing head 5 is mounted is mounted on a feed screw 3 and a guide rod 4 arranged parallel to the platen 1.
is supported. By rotationally driving the feed screw 3 by a motor M via a belt 7, the print head 5 is transported at a constant speed in the space direction indicated by an arrow a.

If the print head is a wire dot type print head, there are a plurality of wires W ₁ , W ₂ ...W ₉ at the tip of the print head 5.
are arranged at equal intervals in the direction perpendicular to the space direction, and while the print head 5 is spaced at a constant speed, the wires _{W 1 ,} W _{2 .} . . By selectively driving and protruding the dots using an electromagnet built into the head, a combination of dots D...for example, "A" is formed on the paper 2.
Characters like this are formed. Note that if the printing paper 2 is pressure-sensitive paper, the wires W ₁ , W ₂ ... are driven and the impact when the wire tips hit the paper 2 will cause the dots D... to be recorded, but for plain paper In this case, an impact is applied via the ink ribbon 8 as shown in FIG.

A in Figure 3 is an enlarged view of the printed pattern;
B is a time chart showing the timing of dot recording by the print head. In B, T indicates a print command timing signal, and E indicates an excitation signal for the electromagnet. Now, assuming that the print head is spacing rightward with respect to the paper 2 at a constant speed as shown by arrow a', the arrival of the first print command timing signal _T1 causes the wire _{W1 to}
The driving electromagnet of the wire _{W9 at the lower end of ~W9 is} excited by the excitation signal _E1 , and as a result, at time _t1 , a dot _D9 is recorded on the wire _W9 . In addition,
Generation time of print command timing signal T ₁ and excitation signal E ₁ and time T ₁ when dot D ₉ was actually recorded
The discrepancy between the two is due to the operating time from when a driving force is applied to the wire by the excitation of the electromagnet until the tip of the wire reaches the paper 2. Next, with the arrival of the second print command timing signal _T2 , the electromagnet of the second wire _W8 from the bottom is excited by the excitation signal _E2 , and the wire _W8 causes a dot to be printed at time _t2. D ₈ is recorded. Thereafter, in the same manner, dots D ₇ , D ₆ , . . . are recorded according to print command timing signals T ₃ , T ₄ , . If two or more dots are required in the vertical direction, such as from time _t5 to _t13 , two or more dots are recorded with one print command timing signal. For example, time t ₅
In this case, the driving electromagnets of wires W ₇ and W ₅ are excited at the same time, and the wires W ₇ and W ₅ are actuated simultaneously to record two dots D ₇ and D ₅ at the same time.

Figure 4 shows the print command timing signal in Figure 3 (b).
T ₁ , T ₂ ... and the excitation signal E ₁ of the wire drive electromagnet,
This is an expanded view of the relationship with E ₂ .
Since there is a minimum necessary distance between the wires W ₁ , W ₂ . Since it takes a considerable amount of time to record data, it is necessary to continue excitation for at least the time indicated by L. In addition, considering the variation in the spring pressure of the wire return spring provided for each electromagnet mechanism, it is necessary to Since the excitation time must be set based on the slower wire, the excitation signal
There is a limit to how short E ₁ , E ₂ ... can be made. In addition, if the excitation by the excitation signal _E1 is not completed,
Next print command timing signal T ₂ and excitation signal
Since E ₂ cannot be input, the printing speed of the printer ends up depending on the length of the excitation signals E ₁ , E ₂ . . . .

Not satisfied with the current state of the art, the present invention aims to further increase the printing speed. That is, since there is a limit to shortening the length of the excitation signal E, as shown in _FIG .
The length of E ₂ is the same as before, and for only a certain time l ₂ , the excitation signal E ₁ based on the print command timing signal T ₁ ′ is also based on the immediately next adjacent print command timing signal T ₂ ′. An excitation signal _E2 is also generated at the same time to enable excitation. To explain this based on FIG. 3, while the electromagnet of wire W ₉ is still excited by the excitation signal E ₁ generated by the first print command timing signal T ₁ , the next wire W ₈ starts excitation. That is to say. Of course, it is not possible to drive the same wire, for example W ₉ , continuously at time t ₁ and at the immediately following time t ₂ , so the same wire is driven by two successive print command timing signals. By configuring the pattern in such a way that it is possible to shorten the generation cycle of the print command timing signal and the excitation signal as shown in FIG. 5, it is possible to dramatically improve the printing speed.

Next, a printing control circuit for making such a printing method possible will be explained based on the embodiment shown in FIG. In the figure, 9 is a character generator consisting of a read-only memory (ROM), and when a code corresponding to a character to be printed is input, a character pattern corresponding to the code is output to an output register 10. . Of course, if the character pattern for one character is not all read out at once, but if the _{character pattern for the letter "A" as shown in FIG .} It is output in parts. That is, the first print command timing signal T ₁ provides pattern information to be recorded in dots at time t ₁ (that is, a drive command for the lower end wire W ₉ ).
is output, and the drive electromagnet of wire _W9 is energized. Then, with the second print command timing signal _T2 , the pattern information to be dot recorded at time _t2 (that is _, the drive command for the second wire _W8 from the bottom) is output, Each print command timing signal T ₁ , T ₂ . . . is read out separately and recorded in dots, as when the drive electromagnet is excited. For this purpose, a print command timing signal T is input to the character generator 9 and the output register 10, and in synchronization with the print command timing signal, the character generator 9 outputs a divided pattern and outputs it to the output register. 10, and the contents of the output register 10 are sent out. In the case of the present invention, the contents of the output register 10 are not directly output as an excitation signal to the electromagnet drive circuit 11, but are output via the multiplexer 12 and the print register 13. Further, during a certain time period, that is, time l ₂ when the excitation signals E ₁ , E _{2 .} . . shown in FIG. is output.

Now, from the output register 10, the dot shown in FIG. 3 is output by the print command timing signal T ₁ ' shown in FIG.
Suppose that the excitation signal E ₁ of the division pattern to record D ₉ is output, the excitation signal is stored in the print register 13 via the multiplexer 12,
The electromagnet drive circuit 11 via the print register 13
is input, and the electromagnet of the wire _W9 of the head 5 is energized. In this case, the electromagnet needs to be excited for a time L in FIG. 5, that is, "l ₁ +l ₂ ", and this time is set by timers TM ₁ and TM ₂ . The timers TM ₁ and TM ₂ control the multiplexer 12 so that only the information of the output register 10 is output during the period l ₁ , but during the period l ₂ they also serve to output the information from the OR circuit 14 side. There is. Therefore, the excitation signal
During the first period l ₁ of E ₁ , the multiplexer 12 connects the output register 10 side to the print register 13 and outputs the excitation signal E ₁ to the electromagnet drive circuit 11 by the timer TM ₁ . The electromagnet is thereby energized and the wire W ₉ begins to operate. Next, with the arrival of the second print command timing signal T ₂ ',
The pattern information for recording dot D ₈ is sent from character generator 9 to output register 10 . At this time, the multiplexer 12 is switched to the OR circuit 14 side by timer _T2 . Therefore, the excitation signal E ₁ previously stored in the print register 13 and the newly generated second excitation signal E ₂ are outputted via the OR circuit 14, and this relationship is set by the timer TM ₂ . It takes place for a period l ₂ . Therefore, by outputting the contents of the print register 13 from the OR circuit 14, excitation is continued by the excitation signal _E1 during the period _l2 , and the necessary minimum excitation is required. Time L is secured. At the same time, the second excitation signal _E2 is also output via the OR circuit 14, so that the electromagnet of the wire _W8 also starts to be excited during the period _l2 . When the timer TM ₂ times up and the period l ₂ elapses, the multiplexer 12 switches to the output register 10 side again, and the excitation signal E ₂ is sent from the output register 10 via the print register 13 to the electromagnet drive circuit. 11. Next, according to the print command timing signal T ₃ ′, the division pattern in which dot D ₃ is to be recorded is output from the character generator 9 to the output register 10, and when the third number excitation signal E ₃ is generated, the multiplexer 12 is turned on again. Switching to the circuit 14 side, during the period _l2 , the rear end of the excitation signal _E2 and the front end of the excitation signal _E3 are simultaneously output, and excitation is performed. Note that the excitation signal is E ₁ ,
When E ₂ , E _{3 ,} etc. occur consecutively, _the excitation _time L is It becomes “l ₁ ′+2 l ₂ ”.

As described above, according to the present invention, during the period _l2 in which the excitation time L overlaps due to the shortening of the generation cycle of the print command timing signals T1 _' , _T2 '..., the previous excitation signal and the current excitation signal are The configuration is such that the previous excitation signal can also be sustained by calculating the logical sum with the excitation signal, so that the electromagnet is excited to record a divided pattern based on a certain print timing signal, and before the excitation ends. Then, it is possible to start excitation of the electromagnet for recording the division pattern based on the next print timing signal. Therefore, by shortening the generation cycle of the print timing signal and the excitation signal while ensuring a sufficient excitation time L of the electromagnet, the printing speed can be significantly improved. For example, when printing characters in a simple pattern such as alphanumeric characters using a print head in which wires for printing Kanji characters are arranged in high density, two consecutive print timing signals cause the same wires to Since it is relatively easy to construct a pattern that does not require driving, a remarkable effect is exhibited in such a case.

Note that some dot printers are non-impact type such as thermal printers, but regardless of the type, a drive signal with a certain drive time corresponding to the excitation signal in a wire dot printer is required, so the present invention can be applied to all types of dot printers, not just wire dot printers.

[Brief explanation of the drawing]

Figure 1 is a plan view of a dot-type serial printer.
Fig. 2 is a front perspective view of the print head, Fig. 3 is a timing chart showing character patterns and the timing of dot recording thereof, Fig. 4 is an enlarged view of the timing chart, and Fig. 5 is a diagram showing the present invention. Figure showing the timing chart according to the method, No. 6
The figure is a block diagram illustrating a print control circuit according to the present invention. In the figure, 2 is the printing paper, 5 is the printing head,
W ₁ , W ₂ ... are wires, D ₁ , D ₂ ... are dots,
T ₁ ′, T ₂ ′... are print command timing signals, E ₁ ,
E ₂ ... is an excitation signal, 10 is an output register, 11
is an electromagnet drive circuit, 12 is a multiplexer, 13
is a print register, 14 is an OR circuit, TM ₁ , TM ₂
is a timer.

Claims (1)

[Claims] 1. A dot-type printing head moves relative to a recording medium on a platen, records dots on the recording medium in synchronization with the relative movement, and forms characters, etc. by combining the dots. In a dot printer for printing, a character generator generates a division pattern corresponding to characters to be printed in synchronization with sequentially arriving print command timing signals, an output register that stores output information of the character generator, and an output of the output register. a print register for storing information; gate means for ORing an output signal of the print register and an output signal of the output register; selection means for alternatively selecting an output from the gate means or an output from the output register. , at least two timer means for generating a drive signal having a fixed time width by alternately receiving the print command timing signal, and the selection means is configured to select a drive signal from only one of the timer means. The output of the output register is selected and outputted to the print register during the period where the output is being output, and the output from the gate means is output to the print register during the period when the drive signal is being output from both of the timer means. dot printer.