JPS585791B2 - Indicator Printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact type high-speed printer using a type conveyor such as a belt, train, chain, etc., and more specifically, to a high-speed impact printer that uses a type conveyor such as a belt, a train, a chain, etc. The present invention relates to a printing hammer control device that corrects the driving time of the printing hammer so that the driving time of the printing hammer always coincides with the pressing time of the printing hammer.

Such type carriers are manufactured by mechanical means, but if the pitch between each type is not within a predetermined range, phenomena such as missing characters and side clipping occur.

Therefore, this mechanical pinch accuracy is required to be extremely strict.

For this reason, type carriers are generally very expensive at present.

In view of the above points, the present invention relaxes the strict mechanical precision required of the type carrier, and electrically compensates for this relaxed mechanical precision.

That is, an object of the present invention is to reduce the mechanical precision required of a type carrier, thereby reducing the manufacturing cost of the type carrier.

Another object of the present invention is to improve printing quality by electrically calculating and determining the drive time of each printing hammer that presses the type on the type carrier.

The present invention will be described below with reference to embodiment drawings in which the type conveyor is limited to a type belt, but it is clear from the following description that it can also be applied to a train chain or the like.

FIG. 1 shows a part of a belt-type printer, and 10 is an endless type belt constituting a type conveyor,
On its outer periphery, type 11 and reference mark 12 (see Figure 3)
and a character mark 13 are engraved.

A pulley 14 drives the type belt 10, and is driven by a drive source such as a motor (not shown) to cause the type belt 10 to travel at a predetermined speed.

15 and 16 are reference marks 1 on the type belt 10.
2 and the character mark 13, and is installed close to the type belt 10.

17 is an ink ribbon, 18 is a printing paper, and 19 is a printing hammer that faces the type belt 10 via the printing paper 18 and the ink ribbon 17, and is biased and driven by an electromagnet 20 as is well known.

The printing method of such a belt type printer will be briefly described below with reference to FIG.

The correspondence between the type characters 11 on the type belt 10 and the printing hammer 19 is 3:4, and the character mark detector 16 detects one character mark 13 until the next character mark 13 is detected. In between, sub-scanning is performed three times, and during each sub-scanning, the printing hammer 19 is driven so that the character to be printed and the printed character 11 match (
In FIG. 2A, the type characters 11 marked with an X are pressed by the printing hammer 19 and printed).

First, in sub-scanning 1, if the character to be printed in the first digit of the printing hammer 19 matches the character 11 on the printing belt 10 corresponding to the printing hammer 19, the printing hammer 19 is driven and the first digit is printed. Characters are printed.

Next, if the character to be printed in the fourth digit of the printing hammer 19 matches the character 11, that is, the character 11 two characters after the character 11 corresponding to the first digit of the printing hammer 19, it will be printed in the same manner as described above. .

From now on, print hammer 9 7.10,13,...1
33, 13' The six-digit characters to be printed are compared with the printed characters 11 corresponding to these printing hammers 19, and if they match, the printing hammers 19 are driven to print.

Subsequently, in sub-scanning 2, the character to be printed by the printing hammer 19 in the second digit is compared with the printed character 11 corresponding to the printing hammer 19, and if they match, the printing hammer 19 is driven to print.

From then on 5, 8, 1 1,..., 131
, 134 digit printing hammer 19 and type 11 corresponding to each digit
If they match, the printing hammer 19 is driven one time to print.

Furthermore, in sub-scanning 3, 3, 6, 9, ..., 132, 1
The 35-digit printing hammer 19 is compared and printed in the same manner.

These sub-scans 1, 2, and 3 constitute one print scan, which is continued until printing for one line is completed.

(See FIG. 2B) Therefore, this printing scan is performed as many times as there are types of characters 11 on the maximum character belt 10.

The above-mentioned correspondence 3:4 between the printing hammer 19 and the printing hammer 19 is a complete correspondence (for example, when the first digit of the printing hammer 19 and a certain printing character 11 correspond, the fourth digit of the printing hammer 19 and the printing character 11 correspond to each other). Instead of completely corresponding to the succeeding printed characters 11), there is a slight deviation Trp as shown in FIG. 2A.

This deviation Trp is caused by the printing hammers 19 being driven simultaneously and pressing the type belt 10 at the same timing.
9, thereby reducing the strength of the type belt 10 and reducing the speed fluctuation of the type belt 10 due to the impact force when the printing hammer 19 is pressed.

Therefore, if this shift is regular, such as 1x, 2x, 3x, etc., then the corresponding printing hammers 19 are delayed by this shift Trp in the sub-scanning, and then The printing hammer 1 is
Each character 11 corresponding to 9 will now match correctly.

That is, as shown in FIG. 3, if the pitches between the characters 11 on the type belt 10, that is, the pitches di between the character marks 13, are all equal or within a predetermined accuracy range, the character mark detector 16 detects the character mark 13, or after a certain period of time, the printing hammer 19 may be driven.

However, if the printing hammer 19 is driven as described above when the accuracy of the pitch d1 is poor, the missing characters and side clipping occur, resulting in poor printing quality.

In order to improve the printing quality, the timing at which the printing hammers 19 are driven may be adjusted for each printing hammer 19.

According to the present invention, the driving timing of the printing hammer 19 is adjusted for each printing hammer 19 in this way.
The present invention will be explained below by limiting to a printing method in which each printing scan is divided into three sub-scans and printing is performed.

In FIG. 4, the distance from the position of the character mark detector 16 to the first digit of the printing hammer 19 is set as Dp, and after the energizing current flows through the drive electromagnet 20 of the printing hammer 19, the printing hammer 19 is placed on the printing belt 10. Let TF be the time required to press type 11, that is, the flight time.
If the type belt 10 is running at a predetermined speed υ, the distance that the type belt 10 moves during the flight time TF can be expressed as DF=υX TF (1).

Therefore, in order for the type 11 to be placed correctly at the center of the first digit of the printing hammer 19, the printing hammer must be moved from the center of the first digit of the printing hammer 19 by a distance DF earlier (indicated by the arrow ↑ in FIG. 4). All you have to do is drive the first digit of 19.

Here, for convenience of the following explanation, the following is assumed.

[) Each flight time TF of each printing hammer 19 is the same for each hammer.

f! ) The pitch (aH in FIG. 4) of each printing hammer 19 is the same over all pitches.

11i) The traveling speed υ of the print bell NO does not change and remains constant.

Now, the first digit of the printing hammer 19 is the type 1 to be printed.
The timing for pressing 1 is when the type character to be printed (13th character mark 13 in FIG. 4) passes point F, as described above.

Therefore, if you know how long it takes for the printed characters 11 to reach point F after the character mark 13 is detected by the character mark detector 16, you can print correctly.

When the character mark 13 is detected by the character mark detector 16, the type 11 printed in the first digit of the printing hammer 19 is the same as the type 11 located nine positions after the detected character mark 13 in FIG. It will be printed.

That is, in FIG. 4, when the fourth character mark 13 is detected, the thirteenth printed character 11 becomes the character printed in the first digit of the printing hammer 19.

The total character pitch from the fourth character mark 13 to the thirteenth character mark 13 can be expressed as follows.

This value DT is not constant because each character pitch di takes various values.

Therefore, correct printing will not be performed if the printing hammer 19 is driven when the character mark detector 16 detects the character mark 13 or after a certain period of time.

Since the distance DP from the character mark detector 16 to the center of the first digit of the printing hammer 19 and the distance DF corresponding to the flight time TF of the printing hammer 19 are constant, the distance between the character to be printed and point F is constant. The distance DD is: DD=DT - (DP+DF) (3).

That is, after detecting the character mark 13 with the character mark detector 16, if you wait for the time when the type 11 to be printed moves by DD and then drive the first digit of the printing hammer 19, correct printing will be performed. .

Since the above DT + DP y D'F is the distance,
Dividing these by the traveling speed υ has the dimension of time.

TT=DT/υ TP=DP/υ TF=DF/υ Here, for DT, since these are, it may be set as d i/v−t i .

That is, the character pitch di can be replaced with the time ti.

Therefore, when the traveling speed υ is constant, the above equation (3) becomes TD-
DD/υ= DT/υ1 (DP+DF)/υ=TT-(
TP+TF), and when the character mark 13 is detected, if the first digit of the printing hammer 19 is driven after a time of , correct printing will be performed.

In this way, the driving timing for the printing hammer 19 in the first digit of the sub-scanning 1 of the printing scanning 1 to correctly press the type 11 is determined.

After the first digit of the printing hammer 19 is driven, 4, 7,...
..., 133, 136 digit printing hammers 19 are driven, but as mentioned above, when the printing hammer 19 of a certain digit completely corresponds to a certain type 11, the next type 11 to be printed is activated.
Since the printing hammer 19 is slightly misaligned, the printing hammer 19 can be driven one after another when the type belt 10 has moved by this amount of misalignment.

However, since this amount of deviation differs for each digit, the timing at which the printing hammer 19 is driven also differs for each digit.

A method for correctly performing this drive timing and performing correct printing will be explained with reference to the timing for driving the fourth digit of the print hammer 19.

The type 11 on the type belt 10 corresponding to the fourth digit of the printing hammer 19 is the 15th type 11 in FIG.

The 13th printed character 11 corresponds to the 1st digit of the printing hammer 19
passes through point F, the 15th character 11 moves from point F to (
It is located at a distance of d13+d1,).

Also, the distance from the center of the first digit to the center of the fourth digit of the printing hammer 19 is three times the hammer pitch ctH.When the 13th printed character 11 matches the center of the printing hammer 19, 1
The fifth type 11 is offset by δ2 from the center of the printing hammer 19, as shown in FIG.

Therefore, after the first digit of the printing hammer 19 is driven, when the printing belt 10 has traveled by δ2, the 4th digit of the printing hammer 19
All you have to do is drive the digits.

This deviation δ2 is δ2=(d13+dl4)-3dH (7)
It is.

When converting this δ into time, since the type belt 10 runs at a predetermined speed υ, t2-δ2/υ
(8) becomes.

That is, after the first digit of the printing hammer 19 is driven, t2
It is only necessary to drive the 4th digit after the time has elapsed.Furthermore, print hammer 1
As shown in Figure 6, the drive timing for the 7th digit of 9 is as follows: t2' = δ2/υ (9) The 7th digit should be driven when the time of t2' = δ2/υ (9) has elapsed after the 4th digit of the printing hammer 19 was driven. Bye.

Here, δ2' is δ2-(dts + d16)-3 dH
(IQ).

From then on 10, 13, 16,...1 3 3, 13
The drive timing for the 6th digit is the printing hammer that was driven before the printing hammer 19 to be driven (for example, the 7th digit for the 10th digit).
t2 (n'=a4) from the drive timing of
” / (J { (di+d(i+1)) 3d
It is sufficient to drive with a delay of H )/v.

The hammer drive timing in sub-scanning 1 printing has been described above, and next, the hammer drive timing in sub-scanning 2 printing will be explained.

The moving distance of the type belt 10 from when the first digit of the printing hammer 19 is driven in the sub-scanning 1 until the second digit of the printing hammer 19 that is first driven in the sub-scanning 2 is correctly printed is the 5th digit.
It is indicated by DMt in the figure.

This DMI" is ?Mt = d1-ctH
(12), so when converted to time, TMx=DM1/L)=(dt3dH)/υ 03)
becomes.

That is, if the second digit of the first printing hammer 19 is driven in sub-scanning 2 at a time delayed by TM1 from the time when the first digit of printing hammer 19 is driven in sub-scanning 1, the 14th type character 11 and printing hammer 19 The second digit of matches.

Here, the driving time of the 1st digit of the printing hammer 19 that is driven first in sub-scanning 1 is set as the reference time, but the driving time of the 136th digit of the printing hammer 19 that is driven last in sub-scanning 1 is the reference time. In this case, the printing hammer 19 may be driven with a delay of TMt'=TMt hΣ 04) from the driving time of the 136th digit.

Is t2Σ printed here? This is the time elapsed from driving the first digit of the symbol 19 to driving the final 136th digit, t2Σ=ΣI 2(n)=1 2+t 2'+t 2'
+...t2←3)+12 (can be expressed as 44.

(15) Subsequent 5,8・
...The driving of the 131st and 134th digits may be performed sequentially using the method described in sub-scanning 1.

That is, the 5th digit of the printing hammer 19 is calculated from the driving time of the 2nd digit as follows: t1=δ1/υ=((d14+dxs) 3dH )/
It is sufficient to drive the printing hammer 1 with a delay of υα6).
The 8th digit of 9 is from the drive time of the 5th digit, tl2'=δ17υ= ((d16+dl?)-3dH
}/υ (17) may be delayed.

The same applies to the subsequent digits 11, 14, . . . 131, 134.

Next, in sub-scanning 3, the type belt runs from the time when the first digit of the printing hammer 19 is driven in sub-scanning 1 until the third digit of the printing hammer 19 that is first driven in sub-scanning 3 is correctly printed. The moving distance of 10 is indicated by DM,' in FIG.

This DMI' is DM2'= (d13+d14)
-2dH (18), and if this is converted into time, TM2'-DM2'/υ={(dl3+dl4) -2
dH}AJ (1st grade).

That is, TMS! 'If the third digit of the printing hammer 19, which is driven first in sub-scanning 3, is driven at a delayed time, the 15th printed character 11 and the third digit of the printing hammer 19 will match.

Also, the printing hammer that is driven first in sub-scanning 2? If the time when the second digit of 9 is driven is the reference time, then type belt 1
The moving distance of 0 is indicated by DM2 in FIG. 5, and since this DM2 is DM2 = d 14 dH (20), in terms of time, it becomes TM2-(dt+'H)/υ (2I).

That is, if the third digit of the printing hammer 19 is driven at a time delayed by TM2 from the time when the second digit of the printing hammer 19 is driven in sub-scanning 2, it will perfectly match the 15th printed character 11.

Subsequent 6, 9, 12, ..., 132 in sub-scanning 3
, 135-digit hammer drive timing is determined in exactly the same manner as in sub-scanning 1 and sub-scanning 2.

In other words, the 6th digit is t22-δ after the 3rd digit is driven.
2/υ−{ (dl4+dl5 ) 3 dH )/
υ (It is sufficient to drive with the delay of (2).

When the printing hammer at the 135th digit is driven, is it sub-scanning? That is, print scan 1 is completed and the process moves to print scan 2. The timing at which sub-scan 1 of print scan 2 is entered will be explained below.

Printing hammer 1 that is driven first in sub-scanning 1 of printing scanning 1
The distance that the type belt 10 moves from the drive time of the first digit of 9 until the first digit of the print hammer 19, which is first driven in sub-scan 1 of print scan 2, is driven is dl2.

Therefore, from the drive time of the first digit of the print hammer 19 in sub-scan 1 of print scan 1, T1=d1/υ
Printing hammer 1 in sub-scanning 1 of printing scanning 2 with only (mu)
All you have to do is drive the first digit of 9.

Printing hammer 1 is driven first in sub-scanning 3 of printing scanning 1
If the drive time of the third digit of 9 is the reference time, the distance that the type 11 on the type belt 10 moves to the center of the first digit of the print hammer 19 in sub-scan 1 of print scan 2 is as shown in Fig. 5. DM
3, and this DMs is DM3=2dH'14
(24). Then, when converted to time, TM3 = (2dH dt4)/υ (25).

Therefore, it is sufficient to drive the print hammer 19 with a delay of TMa from the drive time of the third digit in the sub-scan 3 of the print scan 1.

Furthermore, if the driving time of the 135th digit of the printing hammer 19, which is driven last in the sub-scan 3 of the print scan 1, is the reference time, the 1st digit of the print hammer 19 will be driven in the sub-scan 1 of the print scan 2 after a certain period of time. Just do it.

The drive timing of each print hammer 19 for the subsequent 4th, 7th, .

Assuming that the type belt 10 runs at a predetermined speed υ, each character pitch di is as described above, ti=cti,/υ (27
), and by performing calculations using ti instead of the character pitch di in each equation, correct drive timing can be obtained.

An example of the calculation formula necessary to obtain correct drive timing is shown below.

Note that here TH=dH/υ.

In the above calculation formula, only ti can be considered as a variable, and the other Tr, TF, and TH can be regarded as constants.
The correct drive timing can be determined by measuring and storing the data over all pitches while the motor is traveling at a predetermined speed υ, reading out the variable ti necessary for determining the drive timing, and performing a predetermined calculation.

The process of measuring and storing the variable ti will be explained below with reference to FIG.

In FIG. 7, 71 is a clock pulse generator (hereinafter abbreviated as CPO) which starts oscillation by the output from the reference mark detector 15, and has a predetermined width tw and a predetermined period i.
72 is a gate control circuit (hereinafter referred to as GCC) that generates a gate control output based on the output from the character mark detector 16; 73 and 74 are CPO 71 and GCC 7, respectively;
This is an AND gate that matches the two outputs.

Since the gate control outputs of GCC 72 occur alternately, AND gates 73 and 74 do not open their gates at the same time.

75 and 76 are counters that count the outputs from the AND gates 73 and 74, that is, the clock pulses from CPOT1; 77 is a data selector connected to the counters 75 and 76 via data buses a and b, respectively; Controlled by the output of
8 to be stored.

When the reference mark detector 15 detects the reference mark 12 on the type belt 10, the output causes the CPO 71 to start oscillating and generate the clock pulse of the predetermined period if.

Thereafter, the character mark detector 16 detects the character mark 13 (as shown in FIG. 3, the reference mark 12 and the character mark 13 are on the same vertical line, so they are actually detected at the same time, but the subsequent waveform shaping operation makes it look like the reference mark 13). The mark detector 15 detects it first), and the GCC 72 operates based on its output, and the AND gate 7
3 produces an output that opens that gate.

As a result, the clock pulses of the CPO 71 enter the counter T5 via the AND gate 73 and are counted.

This counting continues until the character mark detector 16 detects the next character mark 13. When the character mark detector 16 detects the next character mark 13, the GCC 72 operates, the AND gate 13 closes its gate, and the AND gate 13 closes its gate. Gate 74 opens the gate.

As a result, counter 76 counts clock pulses from CPO 71.

At the same time, the count value Ni at the counter 75 is
7 into CPM78.

Note that Ni is ti=di/υkitf−Ni (28)
Therefore, the variable ti is converted into the number of pulses Ni and then measured and stored.

From then on, the character mark detector 16 detects character mark 1.
3 is detected, the counters T5 and 76 alternately count clock pulses, and the number of pulses Ni, that is, the variable t
i is measured and stored over all pitches before starting the printing operation.

FIG. 8 is a block diagram of an arithmetic comparison circuit for determining drive timing.

Reference numeral 81 denotes a character pitch memory address control counter (hereinafter abbreviated as CPAC), which specifies an address within the CPM 78.

82 indicates the period t of the clock pulse for the TH, TP, and TF.
Number obtained by dividing by f N H t N P t NF
83 is an arithmetic data memory address control counter (hereinafter abbreviated as DAC) that specifies the address of a82; 84, 86 and 88 are X registers; These are the Y register and the Z register.

87 is a logic operation unit (hereinafter abbreviated as ALU) that receives data from the X register 84 and Y register 86 and performs the above-mentioned operations for determining drive timing.
The operation is controlled by ALU control logic 85.

Further, the calculation result of the ALU 87 is stored in the Z register 88.

89 is an address counter control (hereinafter abbreviated as ACC) which receives the output from the character mark i detector 16 and determines which character mark 13 (number from the reference mark 12) has passed through the character mark detector 16. The CPAC 81 and DAC 83 are controlled by the output thereof.

90 is a clock logic which counts clock pulses having exactly the same width tw and the same period tf as the pulses of the CPO 71 and sends the calculation result to the ALU 87, and its operation is controlled by the output from the character mark detector 16. .

The process of calculating and determining the drive timing will be described below with reference to FIGS. 4 and 8.

It is assumed that before this, the character pitch on the type belt 10 is measured over the entire pitch by the number Ni of clock pulses converted into time as described above, and is stored in the CPM 73.

When the character mark detector 16 detects the character mark 13, the ACC 89 determines that it is the fourth mark, and stores it in the CPAC 81.

At the same time, clock logic 90 begins counting the clock pulses.

The character pitch data t4, that is, N4, stored at the address of the CPM 78 designated by the CPAC 81 is read out, and this N4 is stored in the X register 84.

Next, the CPAC 81 is incremented by 1, and data N3 is read from the CPM 78 and stored in the Y register 86.

After that, N4 stored in X, Y register 84.86
, N,, are added by ALU87 and the value (N4 + N5
) in the Z register? Temporarily store it in 8 and then write it to X register 8.
4 to be memorized.

Further, the CPAC 81 is counted up by 1, and data N is read out from the CPM 78 and placed in the Y register 86.

Here, the data of the X, Y register 8486 is transferred to ALU8 again.
7, and the result (N4+N5+N6) is stored in the Z register 88 and then in the X register 84.

Repeat the above operations and add up to N1, and
Store the value in 4.

Next, the ADM82 in which Np is stored in the DAC83
, read Np, and store it in the Y register 86.

Here, the ALU 87 converts the data of the X register 84 into Y
The data in the register 86 is subtracted, and the subtraction result is stored in the Z register 88 and then stored in the X register 84.

After that, change the DAC83 and use the ADM where NF is stored.
Specify address 82, read NF and write Y register 86.
X. The data in the Y register 86 is subtracted from the data in the register 84, and the result is stored in the X register 84.

As described above, the drive timing of the first digit of the print hammer 19 that is driven first in the sub-scan 1 of the print scan 1 has been determined, and after that, the calculation result from the X register 84 {. ΣN
i - (Np + Np)) and clock logic 90
The ALU 87 compares the counted values of , and when the counted value of the clock logic 90 matches the calculation result, a signal is output from the comparison output terminal of the ALU 87.

This signal becomes the signal that drives the first digit of the printing hammer 19 (of course, before this, the characters to be printed and the type 11 on the type belt 10 are compared, and the drive signal is issued only when they match. It has become).

Note that clock logic 90 is cleared by this match output signal from ALU 87.

The fourth and subsequent digits are determined as follows.

First, the address of the CPM 78 where N12 is stored is specified by the counter of the CPAC 81, N13 is read out and stored in the X register 84, the CPAC 81 is counted up by 1, and N and 4 are read out and stored in the Y register 86.

Thereafter, the data in the X and Y registers 84 and 86 are added, and the result of this addition (N13+N14) is stored in the X register 84 via the Z register 88.

Next, the DAC 83 specifies the address of the ADM 82 where NH is stored, reads the NH, stores it in the Y register 86, subtracts the data in the Y register 86 from the data in the X register 84, and obtains the result of this subtraction (N13+N14- N
It is stored in the X register 84 via the H-Z register 88.

Here, Y register 86 is subtracted from X register 84 again, and the result (N13+N14-2NH) is added to X register 84.
4 to be memorized.

Further subtracting the data in the Y register 86 results in (N14+N
14-3NH) is obtained and stored in the X register 84.

The ALU 87 compares this calculation result with the counter output of the clock logic 90, which counts clock pulses since the first digit of the printing hammer 19 is driven, and when they match, a drive signal is generated from the comparison output terminal. Ru.

The timing for driving the print hammer for digits 7, 10, . . . , 133, and 136 is determined in the same manner.

In other words, in the case of the 7th digit (N15+N16 3N
H) and for the 10th digit (N17+N18-3NH
) and the counter output of the clock logic 90 that started counting from the time when the previous drive signal was generated,
When a match occurs, a drive signal is generated.

The rest are exactly the same.

The start timing of sub-scanning 2 is the print hammer 19 at sub-scanning 1.
After the 136th digit is driven, it is determined as follows.

The CPAC 81 specifies the address of the CPM 78 where N13 is stored, reads N13 and stores it in the X register 84, and the DAC 83 reads the address of the CPM 78 where NH is stored.
Specify address 32, read NH, and store Y register 86.
to be memorized.

Next, the data in the Y register 86 is subtracted from the data in the X register 84, and the result (N13-NH) is stored in the X register 84 via the Z register 88.

During this time, the clock logic 90 is sending a counter output that has been counting clock pulses since the first digit of the printing hammer 19 was driven in sub-scanning 1 to the ALU 87, and this counter output is sent to the X register 84. When they match, a drive signal is generated from the comparison output terminal of the ALU 87, and this becomes the print hammer drive signal for the second digit of the print hammer 19 that is driven first in sub-scanning 2.

The determination of drive timing in subsequent sub-scanning 2 is carried out in exactly the same manner as in sub-scanning 1.

The start timing of sub-scanning 3 is the print hammer 19 at sub-scanning 2.
After the 134th digit is driven, it is determined as follows.

The CPAC 81 specifies the address of the CPM 78 where N14 is stored, reads N14 and stores it in the X register 84, and the DAC 83 reads the address of the CPM 78 where the NH is stored.
Specify address 82, read NH and write Y register 86.
to be memorized.

Next, the data in the Y register 86 is subtracted from the data in the X register 84, and the result (N1, -NH) is stored in the X register 84 via the Z register 88.

During this time, the clock logic 90 is sending the output of a counter that has been counting clock pulses since the second digit of the printing hammer 19, which is first driven in sub-scanning 2, to the ALU, and this counter output matches the X register 84. When ALU87
A drive signal is generated from the comparison output terminal of
This becomes the third-digit printing hammer drive signal for the printing hammer 19 that is driven first.

The determination of drive timing in subsequent sub-scanning 3 is performed in exactly the same manner as in sub-scanning 1.

Finally, the timing determination when sub-scanning 3 ends, that is, printing scanning 1 ends, and moving to printing scanning 2 will be described.

First, CPM78 where N14 is stored in CPAC81
Specify the address of A, read N14 and store it in the X register 84, and use the DAC 83 to read the address of
Specify the address of DM82, read NH and store it in Y register 86.

Next, the ALU 87 subtracts the data in the X register 84 from the data in the Y register 86, and the result (NH-N14) is sent to the X register 88 via the Z register 88.
It is stored in the register 84.

Furthermore, the data in the X register 84 and the data in the Y register 86 are added by the ALU 87, and the result is (2 NH N
14) is stored in the X register 84 via the z register 88.

During this time, the clock logic 90 sends the output of a counter that counts clock pulses from the time when the third digit of the print hammer 19 is driven first in the sub-scan 3 of the print scan 1 to the ALU 87, and this counter output is sent to the X register 84. When they match, a drive signal is generated from the comparison output terminal of the ALU 87, and this becomes the print hammer drive signal for the first digit of the print hammer 19 that is driven first in the sub-scan 1 of the print scan 2.

The subsequent timing decisions for driving the print hammer can be made in exactly the same way as in print scan 1.

The above calculations and comparisons of ALU 87 are performed under the control of ALU control logic 85.

As described above, the present invention measures and stores the character pitch of the type carrier by converting it into time over the entire pitch, and uses the measured data to electrically calculate and determine the driving time of the printing hammer when driving each printing hammer. As a result, the printing hammer and the center of the type are always aligned, improving printing quality. At the same time, the strict accuracy required for forming type on the type carrier is no longer required, which simplifies the type carrier. It is possible to form the structure in a similar manner, and it is possible to achieve effects such as being able to reduce the cost.

[Brief explanation of the drawing]

The drawings show an embodiment in which the type conveyor of the present invention is limited to a type belt, FIG. 1 is a perspective view showing an outline of the printing section, and FIGS. Correspondence diagram and correspondence diagram of printing scan and each sub-scan, Figure 3 is an enlarged front view of the type belt, Figure 4 is a correspondence diagram of the print hammer and type belt to explain the method of determining drive timing, Figure 5 6 is a diagram showing the correspondence between the printing hammer and each character, FIG. 6 is a drive timing diagram of each printing hammer, FIG. 7 is a block diagram showing a configuration for measuring and storing character pinch, and FIG. 8 is a diagram showing the drive timing of each printing hammer. FIG. 2 is a block diagram showing a configuration for performing calculations and decisions. In the figure, 10 is a type belt (conveyor), 11 is a type, 12 is a reference mark, 13 is a character mark, 16 is a character mark detector, 19 is a printing hammer, 71 is a clock pulse generator (CPO), and 72 is a gate control. circuit (GCC), 75 and 76 are counters, 78 is a character pitch memory (CPM), 81 is a character pitch memory address control counter (CPAC), 82 is an arithmetic data memory (ADM), and 83 is an arithmetic data memory address control counter ( DAC), 84, 86, 8
8 is a register, 81 is an arithmetic logic unit (ALU), 89 is an Andres counter control (ACC), and 90 is a clock logic.

Claims (1)

[Claims] 1. A type carrier having type characters and character marks corresponding to the type characters on its outer periphery, and a plurality of printed characters arranged in line along the printing position to strike the type on the type type carrier. A high-speed printer that has a hammer and a character mark detector that detects the character mark, and prints by dividing each print scan during which the type on the type carrier moves by one type pitch into N sub-scans. Pitch storage means for making the type carrier run at a predetermined speed, dividing each pitch between the character marks by the running speed of the type carrier over all pitches, converting the result into time, and measuring and storing the result; a data storage means for storing a time value obtained by dividing the distance between the centers of the hammers by the traveling speed and converting the value into time; a time measuring means for measuring the elapsed time from the start of the previous drive; and a drive for each printing hammer. At times, the pitch data from the pitch storage means and the time data from the data storage means are read out, the sum of the pitch data of the next (N-1) characters from the last printed character is calculated, and the printing hammer pitch data is calculated from the sum. an arithmetic comparison means that performs an arithmetic operation to determine the drive timing by taking the difference of N times the difference between the two times, and generates a coincidence output when the arithmetic result matches the time from the time measuring means, the output of the arithmetic comparison means; A printing hammer control method characterized in that: is used as a drive timing signal for each printing hammer.