JP2000025215A - Liquid ejection driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eject an ink drop (or ink spray) with good quantitative controllability over a wide dynamic range by suppressing radiation pressure for ink. SOLUTION: A separation circuit 4 divide the value (m) of an ejection signal 21 by a modulus (m1) and a quotient (N) is delivered, as a quotient signal 22, to a modulus pulse train generating circuit 5. On the other hand, a remainder (m2) is delivers, as a remainder signal 23, to a remainder pulse train generating circuit 61. The modulus pulse train generating circuit 5 outputs a modulus pulse train 24 where a pulse train continuous by the modulus (m1) during period (T2) is repeated by the number of the quotient (N) based on the quotient signal 22. The period T2 is set to satisfy a relation; T2=m1.T1+T3 (T1-T3 are positive), where T1 is the period of pulse. In the modulus pulse train 24, pulse is present by the modulus (m1) during the period T2 or no pulse is present. In any case, no pulse is present during the period T3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device for driving a liquid discharge section for discharging ink from an ink liquid surface, and more particularly, to a method in which the number of vibration pulses applied to ink and the number of discharged droplets are paired. The present invention relates to driving of a liquid ejection device that does not always correspond to one.

[0002]

2. Description of the Related Art FIG. 49 is a block diagram showing a configuration of a conventional printer head 10. The printer head 10
An image memory 1 for storing image information to be printed, and a pulse generation circuit 50 for generating a pulse based on the image information
And an ink ejection device 9 for storing the ink 30, and a drive circuit 8 for driving a vibrating body 9a included in the ink ejection device 9 based on the pulse. The vibrating body 9a is vibrated by the drive circuit 8, and the ink discharge device 9 discharges the ink droplet 31. For simplicity, only a portion related to driving of the vibrating body 9a is illustrated, and other control mechanisms and mechanical driving mechanisms are omitted.

FIG. 50 is a timing chart showing pulses generated by the pulse generation circuit 50. It has a waveform in which a single pulse having a pulse width of W repeatedly appears in each cycle T2.

[0004]

In the conventional printer head 10 driven as described above, since one droplet 31 is discharged by one pulse, the image is printed by changing the discharge amount. However, there is a problem that the ejection amount can be controlled only by a large particle in one drop unit.

In order to solve such a problem, a plurality of pulse signals (hereinafter, also referred to as "burst signals") having a smaller cycle than the cycle T2 are continuously generated, and the length of the generated period (the number of pulses) is reduced. A technique for ejecting ink in an amount corresponding to image information has been proposed, for example, in Japanese Patent Application Laid-Open No. Hei 2-303849. In this case, the number of vibration pulses applied to the ink and the number of ejected droplets do not correspond one-to-one, and the ink droplet 31 has a mist shape.

However, when such a technique is used, a burst signal is long and continuous in order to eject a large amount of ink. Since the radiation pressure applied to the ink 30 from the vibrating body 9a increases as the continuous length of the burst signal increases, the control of the surface state of the ink 30 becomes easier as the ink is discharged, as it approaches the end. Therefore, there was a problem that stable ejection could not be obtained.

The present invention has been made in order to solve the above-mentioned problem, and discloses a technique for ejecting ink droplets (or mist-like ink) with good controllability of the amount over a wide dynamic range without continuous burst signals. The purpose is to provide.

[0008]

Means for Solving the Problems Claim 1 of the present invention
And a liquid discharge unit that discharges the liquid by applying vibration to the liquid based on a drive pulse, and an i-th (1 ≦ i), wherein the sum of the values is equal to a discharge set value that determines the discharge amount of the liquid. ≤
A drive pulse generator for generating the drive pulse based on the divided ejection signal of M; 1 ≦ M), wherein the drive pulse is separated from a pulse train continuous by a modulo value that is a positive integer by a predetermined period. An i-th modulating pulse train obtained by repeating the i-th divided ejection signal by an i-th quotient obtained as a positive integer by division by the method, and the i-th modulating pulse train separated from the i-th modulating pulse train by the predetermined period. I-th obtained by division
And an i-th remainder pulse train based on the remainder.

[0009] The invention according to claim 2 is as follows:
2. The liquid ejection driving device according to claim 1, further comprising a conversion table indicating a relationship between a pulse generation state of the drive pulse and the ejection signal.

According to a third aspect of the present invention,
2. The liquid ejection driving device according to claim 1, wherein the i-th divided ejection signal is divided by the method to obtain the i-th quotient and the i-th division signal.
Further comprising: an i-th separation circuit that obtains the remainder, an i-th modulus pulse train generation circuit that outputs the i-th modulus pulse train, and an i-th remainder pulse train generation circuit that outputs the i-th remainder pulse train. . Then, the drive pulse generation unit generates the drive pulse by combining the i-th normal pulse train and the i-th remainder pulse train.

According to a fourth aspect of the present invention,
2. The liquid ejection driving device according to claim 1, wherein the i-th residue pulse train is composed of pulses obtained by repeatedly generating the value of the i-th residue.

According to a fifth aspect of the present invention,
2. The liquid ejection driving device according to claim 1, wherein the i-th remainder pulse train is repeatedly generated by the value of the i-th modulus, and is obtained by the i-th modulus of the i-th remainder value. 3. Of pulses having a duty based on the ratio to the value of

According to a sixth aspect of the present invention,
6. The liquid ejection driving device according to claim 1, wherein the ejection set value is input, and the first to j-th (1 <j ≦ Q; 1 <Q) ejections are performed. 7. The apparatus further includes a dividing circuit that generates a signal. Then, the j-th normal pulse train is represented by a time (j
-1) Pulse generation starts at T0 / Q.

According to a seventh aspect of the present invention, there is provided:
7. The liquid ejection driving device according to claim 6, wherein Q is variable in the division circuit.

[0015] The invention according to claim 8 is as follows.
8. The liquid ejection driving device according to claim 7, wherein the Q is variable during printing.

According to a ninth aspect of the present invention, there is provided:
9. The liquid ejection driving device according to claim 1, wherein a gradation of an image having a predetermined dynamic range is converted so as to match a dynamic range of the liquid ejection driving device. A conversion circuit for generating the ejection set value.

According to a tenth aspect of the present invention, there is provided a liquid discharge driving apparatus for driving a liquid discharge unit that discharges the liquid by applying vibration to the liquid based on a drive pulse, wherein the driving pulse train is generated. A drive pulse generator, wherein the drive pulse train is obtained by repeating a pulse train continuous by a modulo value that is a positive integer by a predetermined period and repeating the discharge quotient value by a predetermined period; A pulse train based on the value of the ejection remainder separated by a period, and the ejection quotient is a positive integer obtained by dividing image information having a value that determines the ejection amount of the liquid using a method that is a positive integer. The ejection remainder has a value obtained by performing a second conversion on the remainder obtained by the division, and has a value obtained by performing a first conversion on an integer quotient.

According to an eleventh aspect of the present invention, there is provided the liquid ejection driving device according to the tenth aspect, wherein the separation circuit for obtaining the quotient and the remainder, and the ejection quotient and the ejection remainder are respectively obtained. It further includes a conversion circuit, a normal pulse train generating circuit that outputs the normal pulse train, and a residual pulse train generating circuit that outputs the residual pulse train. Then, the drive pulse generation unit generates the drive pulse train by combining the normal pulse train and the remainder pulse train.

According to a twelfth aspect of the present invention, there is provided the liquid ejection driving device according to the tenth aspect, further comprising a conversion table indicating a relationship between a pulse generation state of the driving pulse and the image information. Prepare.

According to a thirteenth aspect of the present invention, there is provided the liquid ejection driving device according to the tenth aspect, wherein the remainder pulse train is composed of pulses obtained by repeatedly generating the remainder value.

According to a fourteenth aspect of the present invention, there is provided the liquid ejection driving device according to the tenth aspect, wherein the remainder pulse train is obtained by repeatedly generating the value of the modulus, and the value of the remainder is obtained. Consisting of pulses having a duty based on the ratio of

According to a fifteenth aspect of the present invention, there is provided the liquid ejection driving device according to the first or the tenth aspect, wherein a period of the pulse in the pulse train is variable.

According to a sixteenth aspect of the present invention, there is provided the liquid ejection driving device according to the first or tenth aspect, wherein the predetermined period is variable.

According to a seventeenth aspect of the present invention, there is provided the liquid ejection driving device according to the first or tenth aspect, wherein the method is variable.

According to the present invention, a liquid discharge section for applying a vibration based on a drive pulse to a liquid to discharge the liquid and a predetermined number of continuous pulse trains are separated from each other by a predetermined period. And a drive pulse generating unit that generates the drive pulse by controlling a duty of the burst signal based on a discharge set value that determines a discharge amount of the liquid. It is a driving device.

According to a nineteenth aspect of the present invention, in the liquid discharge driving device according to the eighteenth aspect, the duty of the driving pulse is constant in each of the continuous pulse trains.

According to a twentieth aspect of the present invention, there is provided the liquid discharge driving apparatus according to the nineteenth aspect, wherein the duty of the drive pulse increases sequentially except when it is 0%.

According to a twenty-first aspect of the present invention, there is provided the liquid ejection driving device according to the eighteenth aspect, wherein the duty of the driving pulse differs in a pulse included in each of the continuous pulse trains.

According to a twenty-second aspect of the present invention, in the liquid ejection driving device according to the eighteenth aspect, the duty of the driving pulse is 0% or more than 0% and less than 100%. Taking a binary value as to whether it is a fixed value, dividing the discharge set value by the predetermined number, the pulse trains of the number of quotients obtained as positive integers are all the duty cycles of the pulse trains included in each of the pulse trains. Takes the fixed value, one of the pulse trains, of the pulses contained therein, divides the ejection set value by the predetermined number, and sets the fixed value by the number of remainders obtained as a positive integer. Taking a duty, the pulse trains other than the quotient number of pulse trains and the one of the pulse trains have a duty ratio of 0% for all the pulse trains included in each of the pulse trains.

According to a twenty-third aspect of the present invention, a liquid discharge section for applying a vibration based on a driving pulse to a liquid to discharge the liquid and a predetermined number of continuous pulse trains are separated from each other by a predetermined period. And a drive pulse generation unit that controls the amplitude of the burst signal based on a discharge setting value that determines a discharge amount of the liquid to generate the drive pulse. Drive.

According to a twenty-fourth aspect of the present invention, in the liquid discharge driving device according to the twenty-third aspect, the amplitude of the drive pulse is constant in each of the continuous pulse trains.

According to a twenty-fifth aspect of the present invention, in the liquid discharge driving device according to the twenty-third aspect, the amplitude of the driving pulse is different in a pulse included in each of the continuous pulse trains.

According to a twenty-sixth aspect of the present invention, there is provided the liquid ejection driving device according to the twenty-fifth aspect, wherein the amplitude of the driving pulse includes zero.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a block diagram illustrating a configuration of the printer head 11A according to the first embodiment of the present invention. For the sake of simplicity, only the portion relating to the ejection of droplets is shown, and other control mechanisms and mechanical drive mechanisms are omitted.

In the printer head 11 A, the image memory 1 stores the image information 20 (for example, indicating the gradation) for each pixel, and supplies this to the input amount conversion circuit 2. The input amount conversion circuit 2 supplies the ejection signal 21 obtained by converting the image information 20 in accordance with the dynamic range of the printer head 11A to the separation circuit 4.

FIG. 2 is a conversion table illustrating the conversion in the input amount conversion circuit 2. In general, the dynamic range of the printer head 11A is made larger than the dynamic range of the image information 20, so that the printer head 11A has a margin for control. Here, the case where the gradation indicated by the image information 20 is represented by 16 gradations of 0 to 15 and the ejection signal 21 is represented by 32 gradations of 0 to 31 is illustrated. By performing such conversion, it is possible to control the ink ejection amount so that an image can be appropriately represented without saturation of the gradient. For example, if the gradient indicated by the image information 20 is 10, the value m of the ejection signal 21 is “10”.
Take.

The separating circuit 4 divides the value m of the ejection signal 21 as a dividend by a positive integer divisor (so-called "modulus") m1. Then, the division result (so-called “quotient”, a positive integer) N is given to the normal pulse train generating circuit 5 as a quotient signal 22. The remainder m2 (= m−m1 ×
N) is supplied to the remainder pulse train generating circuit 61 as the remainder signal 23. For example, if m = 10 and m1 = 4, then N
= 2, m2 = 2.

The modulus pulse train generating circuit 5 outputs a modulus pulse train 24 in which a pulse train continuous by the modulus m1 in the cycle T2 is repeatedly generated N times based on the quotient signal 22.
Here, the period T2 is defined as T2 = T1
m1 · T1 + T3 (T1 to T3 are all positive). In this specification, “continuous” refers to a form of a pulse that is repeatedly generated in the same cycle (here, T1). Therefore, adjacent pulses at intervals of different periods (here, T3) are not “continuous”.

In the modulus pulse train 24, a pulse exists by the modulus m1 in the period T2, or no pulse exists. In any case, no pulse exists in the period T3. For example, the period T3 is set in the latter half of the cycle T2.

The remainder pulse train generation circuit 61 generates a pulse train continuous by the remainder m2 in the cycle T2 in which no pulse of the normal pulse train exists, for example, in the next cycle of the last cycle T2 in which the pulse exists by the modulus m1, the remainder pulse train 2
Generated as 5.

The adding circuit 7 adds the normal pulse train 24 and the residual pulse train 25 to generate an added pulse train 26.

FIG. 3 shows a normal pulse train 24 and a residual pulse train 2
5, add pulse train 26, m = 10, m1 = 4, N =
2 is a timing chart illustrating a case where m2 = 2; Regarding the normal pulse train 24, in the first and second periods T2, m1 (=
4) Pulses are continuously generated. No pulse train is generated in the third cycle T2. Regarding the residual pulse train 25, no pulse train is generated in the first and second cycles T2, and m2 (= 2) pulses are continuously generated in the third cycle T2. . Therefore, in the addition pulse train 26, the continuous m1 pulse trains are separated from each other by the period T3 and N (=
2) times, and further with a period T3 apart, m2 consecutive pulses are generated once. Of course, there are cases where the remainder is 0 or 1, but for simplicity of expression, in such a case, the present application also expresses that m2 pulses are generated continuously.

The drive circuit 8 vibrates the vibrating body 9a of the ink ejection device 9 based on the added pulse train 26,
Is applied, and a droplet (including a mist state) 31 is discharged. That is, the drive pulse for vibrating the vibrating body 9a is generated by the addition circuit 7 and the drive circuit 8 by adding the normal pulse train 24 and the residual pulse train 25.

Since the period T3 is provided for each cycle T2, the pulse train does not continuously occur beyond the modulus m1. In other words, the addition pulse train 26 adds up the ejection signal 2
Since the radiation pressure can be prevented from being excessively increased while the pulse having the value m of 1 is generated, the ejection of the amount of ink based on the ejection signal 21 can be stably realized.

The timing setting circuit 40 generates the normal pulse train 24 and the residual pulse train 2 at the timing shown in FIG.
5 is a circuit that defines the timing at which the 5 is generated. The timing setting circuit 40 receives the quotient signal 22 and receives the period NT
A normal pulse train output permission signal 43 that permits the existence of the pulse train in the normal pulse train 24 is output to the normal pulse train generating circuit 5. By adopting such a configuration, the normal pulse train generating circuit 5 may be configured by a signal generator in which a period T2 in which m1 pulses exist in the initial stage and no pulse exists in the remaining period T3 is used as a unit. . In this case, the quotient signal 22 does not need to be supplied to the normal pulse train generating circuit 5.

Further, the timing setting circuit 40 is provided by N · T2
After the delay, the remainder pulse train output permission signal 42 is given to the remainder pulse train generation circuit 61. In this way, the remainder pulse train generating circuit 61 generates the remainder pulse train 25 in the first cycle T2 in which no pulse exists in the normal pulse train 24.

The periods T1 and T2 may be variable. By controlling the period T1 so as to match the fundamental period of the natural vibration of the vibrating body 9a, it is possible to suppress variations in ink ejection even when the fundamental period of the natural vibration of the vibrating body 9a varies from a design value. However, if the response characteristics of the vibrating body 9a are too sensitive, it may be desirable not to accurately match the fundamental period of the natural vibration of the vibrating body 9a with the period T1. This is because even in the case of the vibrating body 9a having the same fundamental period of the natural vibration, the sensitive response characteristics vary greatly in amplitude. In such a case, conversely, the vibrating body 9a
By shifting the period T1 from the basic period, the sensitive response characteristics can be suppressed and the variation can be reduced.

The cycle T2 can be shortened when high-speed printing is required, so that the ejection speed can be increased.
That is, high-speed printing is possible by reducing the length of the period T3. However, it goes without saying that the period T3 needs to be long enough to suppress the increase in the radiation pressure.

In the above description, only the operation of adding the remainder pulse train 25 to the normal pulse train 24 has been exemplified. However, the present invention is not limited to this mode. 24. Further, the surplus pulse train 25 may be interrupted between the normal pulse trains 24 on condition that the period T3 is secured before and after that.

Also, high-speed printing can be performed by increasing the modulus m1 as long as the increase in the radiation pressure can be suppressed. The modulus m1 may be variable depending on the type of ink used. This is for stabilizing the ejection of the ink regardless of the dye system or the pigment system.

Embodiment 2 FIG. 4 is a block diagram showing a configuration of a printer head 12A according to the second embodiment of the present invention. In the printer head 12A, the separation circuit 4, the normal pulse train generation circuit 5, the remainder pulse train circuit 61, and the timing setting circuit 40 of the printer head 11A shown in FIG. 1 are each composed of a pair of separation circuits 4a and 4b, the normal pulse train generation circuit 5a, 5b, the remainder pulse train circuits 61a and 61b, and the timing setting circuits 40a and 40b,
a, 4b and the input amount conversion circuit 2, a discharge signal 21
And a dividing circuit 3 for generating the first and second divided signals 21a and 21b based on the above. The timing setting circuits 40a and 40b are connected not only to the separation circuits 4a and 4b, but also to the division circuit 3. The adder circuit 7 includes normal pulse train generation circuits 5a and 5a.
b, and is connected to each of the residual pulse train circuits 61a and 61b.

The dividing circuit 3 supplies a divided signal 21i to a set including a separating circuit 4i, a normal pulse train generating circuit 5i, and a remainder pulse train circuit 61i (i = a, b,...).
Here, the case of two sets is illustrated,
Three or more sets M may be used.

If the gradient indicated by the image information 20 is 13, the value m of the ejection signal 21 takes "19" based on FIG. In the dividing circuit 3, this value is equalized as much as possible by Q (≦
M) values. Here, Q = M = 2 and m =
19 is divided into ma = 10 and mb = 9, and the respective values are output as divided ejection signals 21a and 21b. In the present embodiment, the divided ejection signal 2 thus obtained
The first embodiment is applied to each of the divided discharge signals 21a and 21b at different locations.
The ink is ejected in an amount corresponding to b. This prevents the ink adhering to the paper from collecting at one location, makes it possible to scatter the ink substantially uniformly, and reduces the visual roughness of printing.

The separation circuit 4a, the normal pulse train generation circuit 5a,
Remainder pulse train generating circuit 61a, timing setting circuit 40
a performs the same operations as those of the separation circuit 4, the normal pulse train generation circuit 5, the residual pulse train generation circuit 61, and the timing setting circuit 40 of the first embodiment, and performs the first normal pulse train 2
4a and a first remainder pulse train 25a are generated. For example, if the separation circuit 4a performs division based on the modulus m1 = 4, the quotient N
A quotient signal 22a indicating a = 2 and a remainder signal 23a indicating the remainder m2a = 2 are supplied to the normal pulse train generation circuit 5a and the remainder pulse train generation circuit 61a, respectively. And m1
A cycle T2 consisting of (= 4) pulses and a pulse-free period T3 is repeated Na (= 2) times to obtain a first normal pulse train 24a, and a first normal pulse train 24a having m2a (= 2) pulses is obtained. Is obtained.

Similarly, the separation circuit 4b, the normal pulse train generation circuit 5b, the remainder pulse train generation circuit 61b, and the timing setting circuit 40b are the separation circuit 4, the normal pulse train generation circuit 5, and the remainder pulse train generation circuit 6 of the first embodiment, respectively.
1. The same operation as the timing setting circuit 40 is performed to generate the second normal pulse train 24b and the second remainder pulse train 25b. For example, if the separation circuit 4b performs the division based on the modulus m1 = 4, the quotient signal 22b indicating the quotient Nb = 2 becomes the remainder m
The remainder signal 23b indicating 2b = 1 is supplied to the normal pulse train generation circuit 5b and the remainder pulse train generation circuit 61b, respectively. Then, a cycle T2 consisting of m1 (= 4) pulses and a pulse-free period T3 is repeated Nb (= 2) times to obtain a second normal pulse train 24b, which has m2b (= 1) pulses. A second remainder pulse train 25b is obtained.

FIG. 5 is a timing chart showing the relationship among the first normal pulse train 24a, the first remainder pulse train 25a, the second normal pulse train 24b, and the second remainder pulse train 25b. The period T0 corresponding to one pixel is divided into a first half of a first divided period Ta and a second half of a second divided period Tb. Of course, if the division number Q is 3 or more, the period T0 is divided into first to Qth division periods. The first divided period Ta has a period, and the second divided period Tb has a period. Since all the pulses of N = 4 can be accommodated in these periods, 32 gradations can be realized.

Only in each of the periods, the first normal pulse train 24a has m1 (= 4) normal pulses. Only during the period, the first residual pulse train 2
5a has a remainder m2a (= 2) pulses. Also, only in each of the periods, the second normal pulse train 24
b has m1 (= 4) modulo pulses. Also, only during the period, the first remainder pulse train 25b has the remainder m2b
It has (= 1) pulses.

The addition circuit 7 adds these four pulse trains to generate an addition pulse train 26 and outputs it to the drive circuit 8. In the example shown in FIG. 5, the addition pulse train 26 has no pulse in the period.

In the same manner as in the first embodiment, it is necessary to set the timing for generating the four pulses at the above timing.
a, 40b function. The dividing circuit 3 additionally provided with the first embodiment has first to Qth
Is generated. Here, Q = M = 2, and the first image division signal 41a is
0a, the second image division signal 41b is supplied to the timing setting circuit 40b.

The timing setting circuit 40a receives the first image division signal 41a and the quotient signal 22a, and outputs the first normal pulse train output permission signal 43a and the first remainder pulse train permission signal 42a to the normal pulse train generation circuit 5a, respectively. And the remainder pulse train generation circuit 61a. Similarly, the timing setting circuit 40b receives the second image division signal 41b and the quotient signal 22b, and receives the second normal pulse train output permission signal 43
b, the second remainder pulse train permission signal 42b is sent to the normal pulse train generation circuit 5b and the remainder pulse train generation circuit 61b, respectively.
Output to

FIG. 6 shows a first image division signal 41a, a second image division signal 41b, and a first normal pulse train output permission signal 4
3A is a timing chart showing a relationship among a first residual pulse train permission signal 42a, a second normal pulse train output permission signal 43b, and a second remainder pulse train permission signal 42b. First
And the second image division signals 41a and 41b are the first
And the second divided periods Ta and Tb. For example, the first
And the second image division signals 41a and 41b are activated in periods 1 and 2, respectively.

The timing setting circuit 40a receives the first image division signal 41a and converts it into a first normal pulse train output permission signal 43a and a first remainder pulse train output permission signal 42a.
And split into First normal pulse train output permission signal 43a
Is activated only during the period of Na · T2, and the first remainder pulse train output permission signal 42a is immediately (Ta−Na · T2) immediately after the activation of the first normal pulse train output permission signal 43a is completed.
Activated only during the period.

Similarly, the timing setting circuit 40b receives the second image division signal 41b and divides it into a second normal pulse train output permission signal 43b and a second remainder pulse train output permission signal 42b. The second normal pulse train output permission signal 43b is activated only during the period of Nb · T2, and the second surplus pulse train output permission signal 42b is immediately activated after the activation of the first normal pulse train output permission signal 43b (Tb− Nb
Activate only for the period of T2).

FIG. 7 (a) shows an image of a dot printed by ink ejected by performing the operation of the first embodiment for each of the plurality of pixels as described above. It is a conceptual diagram. First and second divided periods T
a and Tb, the printing paper also moves, so that the left half and the right half of the area V corresponding to one pixel have dots D respectively.
a and Db are printed. As shown in FIG.
It can be seen that printing is performed more evenly than when one dot Dc is printed in the region V.

Which of the methods described in the first and second embodiments is used depends on the type of ink and paper used, the printing speed,
It can be selected according to the ink ejection speed. If you use ink of a type that easily bleeds,
Alternatively, if printing is performed on easily bleeding paper, it is not desirable to divide the sheet as in the second embodiment. This is because one printed dot is likely to spread, causing deterioration in image quality.
Even when the second embodiment is employed, it is desirable to reduce the number of divisions Q.

In addition, when the printing speed is slower and the ink ejection speed is faster, the bleeding is more likely. Therefore, when the method of the second embodiment is used, the number of divisions Q may be reduced or the method of the first embodiment may be used. desirable.

In the case where the number of divisions Q is controlled in the configuration shown in the second embodiment, the second image division signal 42 is used in order to carry out the method of the first embodiment in which, for example, Q = 1 can be grasped.
It is sufficient that the first image division signal 41a is always activated without activating a. The same applies to the case where the number of divisions Q is controlled when three or more sets of separation circuits 4i, normal pulse train generation circuits i, remainder pulse train generation circuits 61i, and timing setting circuits 40i are provided. Only one of the Q signals needs to be activated. Of course, the number of divisions Q must be less than the number of sets M and a positive integer.

Since the type of ink and paper used, the printing speed, and the ink ejection speed are known before printing, or the degree of bleeding can be determined after printing on a test basis, the dividing number Q is previously set in the dividing circuit 3. Can be set.

Embodiment 3 The first embodiment has shown the case where one dot is printed for one pixel, and the second embodiment has shown the case where a plurality of dots are printed for one pixel. However, it is different depending on the type of the image which method is preferable.

In the case of printing a natural image, a person, or the like, for example, which requires a fine gradation, and performing a so-called soft tone,
It is desirable to use the method of the second embodiment so that the ink attached (printed) on the paper is dispersed and becomes difficult to grasp as dots. On the other hand, the method of the first embodiment is desirable for printing clearly as a binary image like a character, that is, for finishing in a so-called high contrast. More generally, the smaller the required gradient, the larger the number of divisions Q (which can be grasped as Q = 1 in the first embodiment) is required to be large. The third embodiment provides a technique for controlling the number of divisions according to the type of image.

FIG. 8 is a block diagram showing a configuration of a printer head 13A according to the third embodiment of the present invention. FIG.
The image memory 1 for the printer head 12A shown in FIG.
Thus, the point that the image type identification signal 19 is given to the division circuit 3 is added.

The image memory 1 outputs the type of image signal given to the image memory 1, for example, an image type identification signal 19 indicating, for example, a character or a portrait, by a known technique. In other words, the image type identification signal 19 indicates the fineness of the gradation required for the printer head 13A.

The dividing circuit 3 generates
The number of divisions Q is controlled for each image. Therefore, even if printing is in progress, if the content indicated by the image type identification signal 19 changes,
The number of divisions Q also changes, and printing can be performed with the number of divisions corresponding to the gradation of fineness required for an image to be printed.

Embodiment 4 In the first embodiment, the input amount conversion circuit 2 immediately converts the image information stored in the image memory 1, for example, the gradation, into the ejection signal 21, and then obtains the quotient signal 22 and the remainder signal 23 in the separation circuit 4.
However, the order of these processes can be reversed.

FIG. 9 is a block diagram showing a configuration of a printer head 14A according to the fourth embodiment of the present invention. FIG.
Are input amount conversion circuits 2a and 2a.
b, and a separation circuit 4 is provided between these and the image memory 1.

The separation circuit 4 calculates the quotient N and the remainder m2 by dividing the gradient indicated by the image information 20 output from the image memory 1 by the modulus m1, and obtains the quotient signal 221 and the remainder signal 231 respectively.
Output as For example, if m1 = 4, the gradient is 1
In the case of 0, it is obtained as N = 2, m2 = 2.

These are the quotient signal 221 and the remainder signal 231
Are input to the input conversion circuits 2a and 2b, respectively, and are converted into a discharge quotient signal 222 and a discharge residual signal 232 based on conversion tables prepared separately.

FIGS. 10A and 10B are conversion tables prepared for the input conversion circuits 2a and 2b, respectively. For example, the value 2 of the ejection quotient signal 222 is obtained from the table of FIG. 10A corresponding to the value N = 2 of the quotient signal 221, and the value m2 = 2 of the remainder signal 231 is obtained as shown in FIG. , The value 2 of the ejection residue signal 232 is obtained.

The modulus pulse train generation circuit 5 calculates the modulus m1 (= 4)
The cycle T2 including the number of pulses and the period T3 is repeatedly generated by the number of times indicated by the ejection quotient signal 222. The remainder pulse train generating circuit generates pulses of the number indicated by the ejection remainder signal 232. The timing setting circuit 40 receives the ejection quotient signal 222 and sends the normal pulse train output permission signal 43 to the normal pulse train generating circuit 5 in the same manner as in the first embodiment.
To the remainder pulse train generation circuit 61.

In this way, almost the same operation as in the first embodiment can be performed. FIG. 10C is a table showing the relationship between the total number of pulses of the added pulse train 26 obtained by the operation of the printer head 14A and the gradient. The total number of pulses of the addition pulse train 26 can be obtained by multiplying the value of the ejection quotient signal 222 by the quotient m1 and adding the value of the ejection remainder signal 232 to this. For example, when the gradient is 10, it is obtained as 2 × 4 + 2 = 10.

Also in the second to fourth embodiments, the periods T 1, T 2,
Needless to say, the order of the remainder pulse train 25 and the normal pulse train 24 can be interchanged by making 1 variable.

Embodiment 5 FIG. 11 is a block diagram showing a configuration of a printer head 11B according to the fifth embodiment of the present invention. The printer head 11B is the same as the residual pulse train generating circuit 6 of the printer head 11A shown in the first embodiment.
1 has a configuration in which a duty variable circuit 62 is substituted.

The duty variable circuit 62 outputs the remainder signal 23
The remainder pulse train 25 having m1 pulses is generated with a duty corresponding to a value obtained by dividing the remainder m2 by the modulus m1 (ratio of the remainder to the modulus). Printer head 1
Other operations of 1B are the same as the operations of the printer head 11A.

FIG. 12 is a graph showing the relationship between the ratio m2 / m1 and the duty of the remainder pulse train 25 in percentage. As the ratio m2 / m1 approaches 100%, the duty of the remainder pulse train 25 approaches 50%. Here, the maximum value of the duty is set to 50% when the duty of the normal pulse train 24 is assumed to be 50%. Ratio m
If the duty of the remainder pulse train 25 approaches the duty of the normal pulse train 24 as 2 / m1 approaches 100%, the addition pulse train 26 obtained by adding the normal pulse train 24 and the remainder pulse train 25 generates the ejection signal 21. It is clear that it reflects well.

However, the ratio m2 / m1 and the residual pulse train 25
It is not always necessary to make the duty relationship linear,
It is desirable to make adjustments based on the image printed with the actually ejected ink droplets 31. Remainder pulse train 2
This is because the duty of 5 and the amount of the ejected ink droplet 31 are not always linear.

The graph shown in FIG. 12 can be provided in the duty variable circuit 62 as a table.
For example, if the modulus m1 is 4, m2 / m1 = 0, 25, 5
Duty 1 corresponding to four cases of 0, 75 (%)
0, 15, 20, 30 (%) may be stored.

Of course, if the modulus m1 used for the division performed in the separation circuit 4 is also stored in the duty variable circuit 62 in advance, the duty can be obtained by giving the remainder m2 instead of the ratio m2 / m1. . Alternatively, the modulus m can be varied depending on the type of ink used.
The duty variable circuit 62 may input the value of the modulus m1 from the separation circuit 4 so as to correspond to 1.

FIG. 13 shows the normal pulse train 24 and the residual pulse train 2
5, add pulse train 26, m = 10, m1 = 4, N =
2 is a timing chart illustrating the case of m2 = 2, and corresponds to FIG. 3 shown in the first embodiment. For the normal pulse train 24, m1 (= 4) pulses are continuously generated in the first and second cycles T2, respectively, and no pulse train is generated in the third cycle T2, similarly to the printer head 11A. . Here, the duty of the normal pulse train 24 is set to 50%.

In the remainder pulse train 25, no pulse train is generated in the first and second cycles T2, and m1 (= 4) pulses are continuously generated in the third cycle T2. However, the duty is m2 / m1 = 2 /
4 = 50%, and based on FIG.
It is 0%. Therefore, in the addition pulse train 26, the continuous m1 pulse trains are separated from each other by the period T3 and N (=
2) times, a further m1 pulse train is generated once at a predetermined tuty after a period T3.

As described above, in the present embodiment, as in the first embodiment, the radiation pressure is excessively increased while the addition pulse train 26 generates a pulse corresponding to the value m of the ejection signal 21. Therefore, it is possible to stably discharge an amount of ink based on the discharge signal 21.

Of course, various modifications shown in the first embodiment can be applied to the present embodiment.

Embodiment 6 FIG. FIG. 14 is a block diagram showing a configuration of a printer head 12B according to the sixth embodiment of the present invention. The printer head 12B is the same as the remainder pulse train generating circuit 6 of the printer head 12A shown in the second embodiment.
It has a configuration in which 1a and 61b are replaced with duty variable circuits 62a and 62b. Residual pulse train generation circuit 62
The functions of a and 62b are the same as those of the remainder pulse train generating circuit 62 shown in the fifth embodiment, and the operation of the other components is the same as that of the printer head 12A.

Thus, the divided ejection signals 21a, 21a
1b, the ink is ejected to different locations in an amount corresponding to the divided ejection signals 21a and 21b, respectively. As a result, similarly to the second embodiment, it is possible to prevent the ink adhering to the paper from being collected in one place, to make it possible to scatter the ink almost uniformly, and to reduce the visual roughness of printing.

FIG. 15 shows a first normal pulse train 24a, a first remainder pulse train 25a, a second normal pulse train 24b and a second normal pulse train 24b.
5 is a timing chart showing the relationship of the residual pulse train 25b, and corresponds to FIG. 5 shown in the second embodiment.

Only in each of the periods, the first modulus pulse train 24a has m1 (= 4) modulus pulses,
Only during the period, the first remainder pulse train 25a is modulo m
It has one (= 4) pulses. However, the duty of the first residual pulse train 25a is m2 / m1 = 2/4 = 50
%, It is 20% based on FIG.

Only in each of the periods, the second normal pulse train 24b has m1 (= 4) pulses, and only in the period, the first remainder pulse train 25b has m1 (= 4) pulses. Having. However, the duty of the first residual pulse train 25a is m2 / m1 = 1/4 =
15% based on FIG. 12 corresponding to 25%
It has become.

Embodiment 7 FIG. FIG. 16 is a block diagram showing a configuration of a printer head 13B according to the seventh embodiment of the present invention. The printer head 13B is the same as the residual pulse train generation circuit 6 of the printer head 13A shown in the third embodiment.
It has a configuration in which 1a and 61b are replaced with duty variable circuits 62a and 62b.

Accordingly, in the present embodiment, the image type identification signal 1
If the content indicated by 9 changes, the number of divisions Q also changes, and printing can be performed with the number of divisions corresponding to the degree of fineness required for the image to be printed.

Embodiment 8 FIG. FIG. 17 is a block diagram showing a configuration of a printer head 14B according to the eighth embodiment of the present invention. The printer head 14B is similar to the residual pulse train generation circuit 6 of the printer head 14A shown in the fourth embodiment.
1 has a configuration in which a duty variable circuit 62 is substituted.

In the same manner as in the fourth embodiment, the remainder signal 23
Based on the value of 1, for example, the value of the ejection residue signal 232 is obtained from FIG. Then, the duty variable circuit 62 determines the duty of the residual pulse train based on the ratio of the value of the ejection residual signal 232 to the modulus.

In this way, the present embodiment can provide the same effects as in the fourth embodiment.

Embodiment 9 FIG. As described in the first embodiment, when a plurality of pulse trains are generated at intervals of the predetermined period T3, the radiation pressure can stably eject the ink 30 even if the continuous length of the pulse train is long. Become. In order to eject the ink 30 in an amount corresponding to the ejection signal 21, in the first to eighth embodiments, a modulo pulse train 24 and a residual pulse train 25 are generated by division by a certain modulus, and these are added to add an additional pulse train 26. Was getting.

However, without performing such division,
By controlling the duty of the pulse width of the burst signal, an amount of ink 30 corresponding to the discharge signal 21 can be discharged. Then, more precise control can be performed as compared with the case where the ejection amount is controlled based on the number of pulses.

FIG. 18 is a block diagram showing a configuration of a printer head 15 according to the ninth embodiment of the present invention. As in the first to eighth embodiments, only a portion related to ejection of droplets is illustrated for simplicity, and other control mechanisms and mechanical drive mechanisms are omitted.

The printer head 15 is the printer head 1
Similarly to 1A, the image memory 1 stores image information 20 (for example, indicating a gradation) for each pixel, and supplies this to the input amount conversion circuit 2. The input amount conversion circuit 2 outputs the image information 20
To the duty control circuit 63. The above conversion can be performed, for example, based on FIG.

The duty control circuit 63 receives the burst signal 28 from the burst generation circuit 51 and controls the duty by a duty signal (not shown) generated based on the value of the ejection signal 21 to generate the drive signal 27. I do. The drive circuit 8 vibrates the vibrating body 9 a of the ink discharge device 9 based on the drive signal 27, applies vibration to the ink 30, and discharges a droplet (including a mist state) 31. That is, the drive pulse for vibrating the vibrating body 9a is transmitted to the burst signal 28 by the duty control circuit 63 and the drive circuit 8.
And the ejection signal 21.

The burst signal 28 is generated by repeating the same pulse train by a predetermined number of bursts L with the period T2 as one cycle. No pulse is generated in part of the period T2 (for example, the latter half of the period T2), and a pulse of the period T1 is continuously generated by a predetermined number P in the first half period.

FIG. 19A is a timing chart illustrating the burst signal 28. Here, L = 8, P = 4
And The burst signal 28 determines the timing of the rise of the pulse of the drive signal 27.
Is not determined. Therefore, the duty of the burst signal 28 itself does not matter.

The duty control circuit 63 determines the duty of the drive signal 27 based on the value of the ejection signal 21. FIG. 20 is a conversion table exemplifying the value of the duty signal when the value of the maximum ejection signal 21 is 0 to 4. The value of the duty signal is adopted as the duty (%) for the burst signal 28. For example, when the value of the ejection signal 21 is 0, the first to eighth pulse trains (the pulse train number in the present specification indicates the order of the pulse trains forming the burst signal 28 by collecting L pulses, and the i-th pulse train Means the pulse train generated i-th in the burst signal 28 to which it belongs)). Therefore, the drive signal 27
Does not substantially generate a pulse. Of course, the ejection signal 21
May be generated with a certain duty, similar to FIG. 12 shown in the eighth embodiment.

FIGS. 19 (b), (c) and (d) show the duty signal when the value of the ejection signal 21 is 2, respectively.
6 is a timing chart showing a driving signal 27 and a vibration displacement amount of a vibrating body 9a. As shown in FIG. 20, the duties assigned to the first to eighth pulse trains are 0, 0, 0, 30, 30, 0, 0, 0, respectively.
(%), The duty signal shown in FIG. 19B takes these values. However, the value of the duty signal needs to be determined before the burst signal to which it is assigned.

Based on the above-mentioned duty signal, FIG.
As shown in (c), the drive signal 27 is the first to third drive signals.
No pulse exists in the period corresponding to the pulse train and the sixth to eighth pulse trains, and a pulse having a duty of 30% exists in the period corresponding to the fourth and fifth burst pulse trains. Then, as shown in FIG.
The displacement of the vibrating body 9a slightly increases each time a pulse is generated in the drive signal 27, and attenuates when the pulse is no longer generated.

FIG. 21 is a timing chart showing the burst signal 28, the duty signal, the drive signal 27, and the amount of oscillating displacement of the vibrating body 9a when the value of the ejection signal 21 is 3. As shown in FIG. 20, the duties assigned to the first to eighth pulse trains are 0, 40, 40, 40, 40, 40, 40, and 0 (%), respectively. Take these values. Then, as shown in FIG. 21C, the drive signal 27 has no pulse in the periods corresponding to the first, seventh, and eighth pulse trains, and does not have any pulse in the periods corresponding to the second to sixth pulse trains. There is a 40% duty pulse. And the vibrating body 9a
Reflecting that the duty is larger than the case shown in (d), a large displacement is exhibited as shown in FIG.

As described above, in the present embodiment, if a pulse is present in the drive signal 27, the duty is a value uniquely determined with respect to the value of the ejection signal 21. Therefore, the duty of the drive signal 27 can be controlled with a simple table as shown in FIG.

For this reason, the duty signal can be divided into two. FIGS. 22 (a) and 22 (c) respectively show FIG.
FIGS. 22A and 22B are the same as FIGS.
-2) shows two types of duty signals. FIG.
The first duty signal shown in (b-1) determines the value of the duty before the generation of the first pulse train. Then, the second duty signal shown in FIG. 22B-2 is generated prior to the generation of each pulse train of the burst signal 27.
It is determined whether to generate a pulse having the duty. Here, “1” is used when a pulse is generated, and “0” when no pulse is generated.

Further, as shown in FIGS. 19 and 21, pulse trains may be adjacent to each other in the drive signal 27. For example, according to the example shown in FIG. 19, the second pulse train and the fifth pulse train Can be controlled so that a pulse is generated in the drive signal 27 in a period corresponding to Such control may be advantageous in that the density of the print is made uniform. Such control change can be easily performed by changing the table shown in FIG. This is the same in the following embodiments.

Embodiment 10 FIG. By changing the duty other than 0% in the drive signal 27 depending on the value of the ejection signal 21, the change in the excitation of the liquid surface of the ink 30 due to the radiation pressure can be made slower, and more stable ejection can be performed.

FIG. 23 is a conversion table according to the present embodiment, and exemplifies the value of the duty signal when the value of the ejection signal 21 is 0 to 4. Burst signal 2
In FIG. 8, the duty increases as the pulse train occurs later (except for the duty of 0%). In the present embodiment, the rapid application of a large radiation pressure to the surface of the ink 30 is avoided in this way. In addition, for example, as can be understood by comparing the case where the value of the ejection signal 21 is 3 and the case where the value of the ejection signal 21 is 4, even if the pulse train number is the same, the duty is made different to make the above avoidance more effective. . Of course,
Even if the value of the ejection signal 21 is 0, a pulse may be generated with some duty.

FIGS. 24 (a), (b), (c) and (d) show the burst signal 28, the duty signal, the drive signal 27 and the vibrator 9a when the value of the ejection signal 21 is 3, respectively.
5 is a timing chart showing the amount of vibrational displacement, and shows a period in which pulse train numbers are 2 to 6. As shown in FIG. 23, the duties assigned to the second to sixth pulse trains are 20, 30, 40, 50,
Since it is 0 (%), the duty signal shown in FIG. 23B takes these values. The pulse width of the drive signal 27 is gradually increased to reflect these duties, and the displacement of the vibrating body 9a is also increased. However, the burst signal 28 does not generate a pulse corresponding to the sixth pulse train to which the duty of 0% is assigned.

FIGS. 25 (a), (b), (c) and (d) show the burst signal 28, the duty signal, the drive signal 27 and the vibrator 9a when the value of the ejection signal 21 is 4, respectively.
5 is a timing chart showing the amount of vibrational displacement, and shows a period in which pulse train numbers are 2 to 6. As shown in FIG. 23, the duties assigned to the second to sixth pulse trains are 30, 40, 50, 50, and 50, respectively.
Since the duty ratio is 50 (%), the duty signal shown in FIG. 24B takes these values, and the drive signal 27 gradually increases in pulse width reflecting these duties, and the displacement amount of the vibrating body 9a Also gets bigger.

As described above, according to the present embodiment, it is possible to avoid suddenly applying a large radiation pressure to the surface of the ink 30, and to stably eject the ink droplet 31.

Embodiment 11 FIG. 26 and 27 are conversion tables according to the present embodiment, and exemplify the values of the duty signal when the value of the ejection signal 21 is 0 to 4. In these figures, the pulses generated in each pulse train constituting the burst signal 28 are 1 in order from the beginning.
Waves, two waves, three waves, and four waves are shown. As can be seen from FIGS. 26 and 27, the duty increases as the pulse is generated later (except for the duty of 0%). In the present embodiment, the rapid application of a large radiation pressure to the surface of the ink 30 is avoided in this way. Moreover, although more complicated than the conversion table shown in the tenth embodiment,
Even if the pulses are generated in the same order in the same pulse train, the duty is made different to make the above avoidance more effective. Of course, even if the value of the ejection signal 21 is 0, a pulse may be generated with some duty.

FIGS. 28 (a), (b), (c) and (d) show the burst signal 28, the duty signal, the drive signal 27 and the vibrator 9 when the value of the ejection signal 21 is 1, respectively.
6 is a timing chart showing the amount of vibrational displacement a.
As for the first pulse train, the duty signal has one or more waves.
In order to assign duties of 20, 30, 40, and 50 (%) to the four waves respectively, these values are determined immediately before each pulse. The drive signal 27 reflects these duties, and the generated pulse width gradually increases. When the value of the ejection signal 21 is 1, the duty assigned to the first to fourth waves is 0% in any of the second to eighth pulse trains, so that the drive signal 27 corresponds to these periods. No pulse is generated.

FIGS. 29 (a), (b), (c), and (d) show the burst signal 28, the duty signal, the drive signal 27, and the vibrator 9 when the value of the ejection signal 21 is 2, respectively.
6 is a timing chart showing the amount of vibrational displacement a.
As for the first pulse train, the duty signal has one or more waves.
In order to assign duties of 30, 40, 50, and 60 (%) to the four waves, these values are determined immediately before each pulse. The drive signal 27 reflects these duties, and the generated pulse width gradually increases. The same applies to the second pulse train. When the value of the ejection signal 21 is 2, the duty assigned to the first to fourth waves is 0% in any of the third to eighth pulse trains, and the drive signal 27 corresponds to these periods. No pulse is generated.

In each of the cases shown in FIGS. 28 and 29, the vibrating body 9a reflects the waveform of the drive signal 27 whose pulse width increases in each of the pulse trains according to the ninth embodiment. , 10, the displacement is significantly increased, and thereafter, the displacement attenuates as the pulse of the drive signal 27 stops being generated. Therefore, the ink droplet 31 can be ejected stably.

In FIGS. 26 and 27, one wave to one wave are shown.
The duty pattern assigned to the four waves is uniquely determined with respect to the value of the ejection signal 21. Therefore, similar to the mode shown in FIG. 22, two types of duty signals, a first duty signal for determining a duty pattern and a second duty signal for determining whether or not a pulse is generated, are employed. be able to.

Of course, the duty pattern assigned to the first to fourth waves is not uniquely determined with respect to the value of the ejection signal 21. For example, when the value of the ejection signal 21 is 2,
The first pulse train and the second pulse train may be different. That is, the duty patterns assigned to the first to fourth waves in the first pulse train are 20, 30, 40, and 50.
(%), And the duty patterns assigned to the first to fourth waves in the second pulse train are 30, 40, and 5
It may be 0,60 (%).

Further, the duty pattern assigned to the 1st to 4th waves is such that the duty is 0%, for example, 50%.
It may be a binary pattern of whether the value is larger than 0% and smaller than 100% fixed to%. Since the case where the duty is 100% is excluded, the burst signal 2
In this case, the pulses constituting 8 are not connected to each other. In this case, the number of pulses in each pulse train is substantially defined.

In addition, the addition pulse train 26 shown in FIG. 3 in the first embodiment can also be obtained by the configuration shown in FIG. Specifically, 1 to 4 pulses are generated so that m1 pulses are generated in the first to kth pulse trains, m2 pulses are generated in the k + 1th pulse train, and no pulses are generated in the k + 2 to 8th pulse trains. This can be realized by setting the duty to 0%. FIG. 30 and FIG.
Reference numeral 1 denotes a part of the conversion table adopted in that case.

Similarly, the addition pulse train 26 as shown in FIG. 5 in the second embodiment can be obtained with the configuration shown in FIG. FIG. 32 and FIG. 33 show a part of the conversion table adopted in that case.

Similarly, in Embodiment 4, FIG.
18 can also be obtained with the configuration shown in FIG. FIG. 34 and FIG. 35 show a part of the conversion table adopted in that case.

Embodiment 12 FIG. FIG. 36 is a block diagram showing a configuration of the printer head 16 according to the twelfth embodiment of the present invention. The printer head 16 supplies the image information 20 for each pixel stored in the image memory 1 to the input amount conversion circuit 2 in the same manner as the printer head 15. Input amount conversion circuit 2
Converts the image information 20 to match the dynamic range of the printer head 16 and obtains a discharge signal 21. The ejection signal 21 is provided to a driver control circuit 64, which outputs the ejection signal 21 and the burst generation circuit 51.
To obtain the first and second drive signals 271, 272.

The first and second drive signals 271 and 272 are supplied to first and second drive circuits 81 and 82, respectively.
However, both the first and second drive circuits 81 and 82 generate a pulse having the drive voltage Vo in accordance with a rule described later. These are given to one end of each of the resistors R1 and R2 (hereinafter, the resistance values are also assumed to be R1 and R2, respectively, and R1> R2). The other end of each of the resistors R1 and R2 is grounded via the vibrating body 9a of the ink discharge device 9. Therefore, assuming that the impedance of the vibrating body 9a is Zo,
The value (amplitude) of the voltage Vd applied to a is R1, R2,
Various values defined by Zo and Vo are adopted. As described above, the driving pulse for vibrating the vibrating body 9a is generated by the driver control circuit 64 and the first and second driving circuits 81 and 82 based on the burst signal 28 and the ejection signal 21.

As described in the ninth embodiment, the burst signal 28 is generated by repeating the same pulse train for a predetermined number of bursts L with the period T2 as one cycle. No pulse is generated in part of the period T2 (for example, the latter half of the period T2), and a pulse of the period T1 is continuously generated by a predetermined number P in the first half period. Hereinafter, for example, L = 8 and P = 4.

FIGS. 37 and 38 show conversion tables indicating the value of the voltage Vd with respect to the ejection signal 21. FIG. V1 = Zo
Vo / (R1 + Zo), V2 = Zo · Vo / (R2 + Z
o), V3 = Zo · Vo · (R1 + R2) / (R1 · R
2 + Zo · (R1 + R2)), and V1 <V2 <V3
It is. As described above, even if the amplitude, rather than the duty, of the drive pulse for vibrating the vibrating body 9a is controlled, more precise control is performed as compared with the case of controlling the ejection amount using the number of pulses as in the ninth embodiment. It can be performed.

In order to obtain the value of the voltage Vd shown in FIGS. 37 and 38, the presence or absence of the pulse of the first drive signal 271 is determined by the conversion table shown in FIGS. Are determined by the conversion tables shown in FIGS. 41 and 42, respectively. A pulse is generated in the first drive signal 271 only when the voltage Vd generates a pulse to be V1 and V3, and a pulse is generated in the second drive signal 272 only in a portion where the voltage Vd generates a pulse to be V2 and V3. Occurs. FIG.
3, the first signal generated when the value of the ejection signal 21 is “1”.
A timing chart showing an example of a pulse train is shown.

The P pulses in each pulse train may all be made variable with the same voltage Vd. In this case, the table can be simplified for each pulse train. FIG. 44 shows the value of the voltage Vd with respect to the ejection signal 21 in such a case.

FIGS. 45 and 46 are conversion tables showing other aspects of the value of the voltage Vd with respect to the ejection signal 21. FIG. As described above, the amplitudes assigned to the 1st to 4th waves included in each of the pulse trains may be both 0 and non-zero. In this case, the pulse train allows fewer than P pulses. Of course, the amplitude pattern assigned to the first to fourth waves may be a binary pattern indicating whether the amplitude is 0 or a fixed non-zero value. In this case, the number of pulses in each pulse train is substantially defined.

In the amplitude patterns shown in FIGS. 44 to 46, the pulse is generated in the first drive signal 271 only when the voltage Vd generates a pulse that should be V1, V3, and the voltage Vd becomes V2, V3. This can be realized by generating a pulse in the second drive signal 272 only at a position where a pulse to be generated is generated.

Embodiment 13 FIG. FIG. 47 is a block diagram showing a configuration of the printer head 17 according to Embodiment 13 of the present invention. As in the twelfth embodiment, the printer head 17 has the value (amplitude) of the voltage Vd applied to the vibrating body 9a.
Control.

The printer head 17 is the printer head 1
Similarly to 5, the input signal conversion circuit 2 obtains the ejection signal 21 from the image information 20 for each pixel stored in the image memory 1. The ejection signal 21 is given to a drive voltage generation circuit 65,
The level setting signal 29 is given to the drive circuit 8. Drive circuit 8
Applies a voltage Vd to the vibrating body 9a based on the level setting signal 29 and the burst signal 28 from the burst generating circuit 51.

The level setting signal 29 is shown in FIGS.
8, or the values 0, V1, V2, and V3 in the conversion tables of FIGS. The drive circuit 8 modulates the burst signal 28 so as to make this value the amplitude. FIG. 48 exemplifies a timing chart showing a form of the first pulse train generated when the value of the ejection signal 21 is “1”.

Modification of Embodiment. As can be said for all the embodiments, as exemplified in the ninth to eleventh embodiments, the displacement of the vibrating body 9a is displaced like a pulse.
In this regard, the drive signal 27 may be provided to the vibrating body 9a after passing through a filter in a desired band. The filter may have an inductive component. By controlling the characteristics of such a filter, it is possible to improve the resonance with the vibrating body 9a and efficiently drive the vibrating body 9a.

[0143]

According to the liquid ejection driving apparatus of the present invention, the total number of pulses is based on the ejection set value while the number of continuous pulse trains is suppressed to a modulus value or less. Since the addition pulse train is obtained, it is possible to suppress the radiation pressure that gradually increases as the number of consecutive pulse trains increases, thereby enabling stable liquid ejection.

According to the liquid ejection driving device of the present invention, one pixel is divided into Q and ink is ejected in each of the divided sections, so that the ink can be uniformly dispersed. In addition, the visual roughness of printing is reduced.

According to the liquid ejection driving apparatus of the present invention, when printing is easily blurred due to the type of ink or paper and printing speed, the number of divisions Q is reduced and the spread of dots to be printed is reduced. Can be suppressed.

According to the liquid ejection driving apparatus of the present invention, the number of divisions is increased or decreased according to the type of image during printing, for example, the degree of gradation required for the image. be able to. For example, the division number Q can be reduced if a high contrast is required like a character, and the division number Q can be increased if a low contrast is required like a portrait.

According to the ninth aspect of the present invention, it is possible to discharge the ink so that the gradation is appropriately expressed without saturating the gradation of the image.

[0148] Claims 10 to 14 of the present invention.
According to the liquid ejection driving device, the dynamic range of the gradation of the image can be converted to match the dynamic range of the liquid ejection driving device while suppressing the number of continuous pulse trains to a value not more than the modulus. Therefore, it is also possible to suppress the radiation pressure that gradually increases as the number of continuous pulse trains increases, to discharge a stable liquid, and to discharge the ink so that the gradation is not saturated and the image is appropriately expressed. it can.

According to the liquid discharge driving device of the present invention, even if the fundamental period of the natural vibration of the mechanism for applying vibration to the liquid varies from the design value, the period of the pulse is controlled, Variations in ink ejection can be suppressed.

According to the liquid ejection driving device of the present invention, it is possible to improve the printing speed while suppressing the radiation pressure.

According to the liquid ejection driving device of the eighteenth aspect of the present invention, the liquid is ejected by applying vibration to the liquid based on the drive pulse generated by controlling the duty of the burst signal. The radiation pressure that gradually increases as the number of continuous liquids increases can be suppressed, so that stable liquid discharge can be performed.

According to the liquid discharge driving apparatus of the nineteenth aspect of the present invention, a drive pulse based on the discharge set value can be obtained with a simple control.

According to the liquid discharge driving device of the present invention, it is possible to avoid a sudden large radiation pressure from being applied to the surface of the liquid with relatively simple control, and to discharge the liquid more stably. It can be carried out.

According to the liquid discharge driving apparatus of the present invention, it is possible to avoid suddenly applying a large radiation pressure to the surface of the liquid for each pulse train, and to perform more stable liquid discharge. .

According to the liquid discharge driving device of the present invention, the pulse train based on the discharge set value is obtained while the number of continuous pulse trains is suppressed to a value not more than the modulus value. The radiation pressure that gradually increases as the pressure increases can be suppressed, so that stable liquid ejection can be performed.

According to the liquid discharge driving device of the present invention, the liquid is discharged by applying vibration to the liquid based on the drive pulse generated by controlling the amplitude of the burst signal. The radiation pressure that gradually increases as the number of continuous liquids increases can be suppressed, so that stable liquid discharge can be performed.

According to the liquid discharge driving device of the present invention, it is possible to obtain a drive pulse based on the discharge set value with a simple control.

[0158] Claims 25 and 26 of the present invention.
According to the liquid discharge driving device according to (1), it is possible to avoid suddenly applying a large radiation pressure to the surface of the liquid for each pulse train, and to perform more stable liquid discharge.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration according to a first embodiment of the present invention;

FIG. 2 is a diagram showing a conversion table illustrating an operation of the first embodiment of the present invention;

FIG. 3 is a timing chart illustrating an operation of the first exemplary embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration according to a second embodiment of the present invention;

FIG. 5 is a timing chart illustrating an operation of the second exemplary embodiment of the present invention.

FIG. 6 is a timing chart illustrating the operation of the second embodiment of the present invention.

FIG. 7 is a conceptual diagram illustrating an effect of the second embodiment of the present invention.

FIG. 8 is a block diagram illustrating a configuration according to a third embodiment of the present invention;

FIG. 9 is a block diagram illustrating a configuration according to a fourth embodiment of the present invention;

FIG. 10 is a diagram showing a conversion table illustrating an operation according to the fourth embodiment of the present invention.

FIG. 11 is a block diagram illustrating a configuration of a fifth embodiment of the present invention.

FIG. 12 is a graph illustrating an operation of the fifth embodiment of the present invention.

FIG. 13 is a timing chart illustrating the operation of the fifth embodiment of the present invention.

FIG. 14 is a block diagram illustrating a configuration of a sixth embodiment of the present invention.

FIG. 15 is a timing chart illustrating the operation of the sixth embodiment of the present invention.

FIG. 16 is a block diagram illustrating a configuration of a seventh embodiment of the present invention.

FIG. 17 is a block diagram illustrating a configuration of Embodiment 8 of the present invention;

FIG. 18 is a block diagram illustrating a configuration of a ninth embodiment of the present invention.

FIG. 19 is a timing chart illustrating the operation of the ninth embodiment of the present invention.

FIG. 20 is a diagram showing a conversion table illustrating an operation according to the ninth embodiment of the present invention;

FIG. 21 is a timing chart illustrating the operation of the ninth embodiment of the present invention.

FIG. 22 is a timing chart illustrating the operation of the ninth embodiment of the present invention.

FIG. 23 is a diagram showing a conversion table illustrating an operation of the tenth embodiment of the present invention.

FIG. 24 is a timing chart illustrating the operation of the tenth embodiment of the present invention.

FIG. 25 is a timing chart illustrating the operation of the tenth embodiment of the present invention.

FIG. 26 is a diagram illustrating a conversion table illustrating an operation according to the eleventh embodiment of the present invention;

FIG. 27 is a diagram showing a conversion table illustrating an operation of the eleventh embodiment of the present invention.

FIG. 28 is a timing chart illustrating the operation of the eleventh embodiment of the present invention.

FIG. 29 is a timing chart illustrating the operation of the eleventh embodiment of the present invention.

FIG. 30 is a diagram illustrating a conversion table illustrating another operation of the eleventh embodiment of the present invention.

FIG. 31 is a diagram illustrating a conversion table illustrating another operation of the eleventh embodiment of the present invention.

FIG. 32 is a diagram illustrating a conversion table illustrating another operation of the eleventh embodiment of the present invention.

FIG. 33 is a diagram illustrating a conversion table illustrating another operation of the eleventh embodiment of the present invention;

FIG. 34 is a diagram illustrating a conversion table illustrating another operation of the eleventh embodiment of the present invention.

FIG. 35 is a diagram illustrating a conversion table illustrating another operation of the eleventh embodiment of the present invention.

FIG. 36 is a block diagram illustrating a configuration of a twelfth embodiment of the present invention.

FIG. 37 is a diagram showing a conversion table illustrating an operation of the twelfth embodiment of the present invention.

FIG. 38 is a diagram illustrating a conversion table illustrating an operation according to the twelfth embodiment of the present invention;

FIG. 39 is a diagram illustrating a conversion table illustrating an operation of the twelfth embodiment of the present invention;

FIG. 40 is a diagram showing a conversion table illustrating an operation according to the twelfth embodiment of the present invention.

FIG. 41 is a diagram showing a conversion table illustrating an operation according to the twelfth embodiment of the present invention;

FIG. 42 is a diagram illustrating a conversion table illustrating an operation of the twelfth embodiment of the present invention;

FIG. 43 is a timing chart illustrating the operation of the twelfth embodiment of the present invention.

FIG. 44 is a diagram showing a conversion table illustrating an operation of the twelfth embodiment of the present invention.

FIG. 45 is a diagram showing a conversion table illustrating an operation of the twelfth embodiment of the present invention.

FIG. 46 is a diagram illustrating a conversion table illustrating an operation of the twelfth embodiment of the present invention.

FIG. 47 is a block diagram illustrating a configuration of a thirteenth embodiment of the present invention;

FIG. 48 is a timing chart illustrating the operation of the thirteenth embodiment of the present invention.

FIG. 49 is a block diagram showing a configuration of a conventional technique.

FIG. 50 is a timing chart showing the operation of the conventional technique.

[Explanation of symbols]

2, 2a, 2b input amount conversion circuit, 3 separation circuit, 4,
4a, 4b Separation circuit, 5, 5a, 5b method pulse train generation circuit, 7 addition circuit, 8 drive circuit, 9 ink ejection device, 9a vibrator, 21 ejection signal, 22, 221
Quotient signal, 23,231 remainder signal, 27 drive signal, 2
8 burst signal, 30 ink, 31 droplets, 51 burst generation circuit, 61, 61a, 61b surplus pulse train generation circuit, 62, 62a, 62b duty variable circuit, 63 duty control circuit, 222 ejection quotient signal,
232 Discharge surplus signal.

Claims (26)

[Claims] A liquid ejecting unit for ejecting the liquid by applying a vibration based on a driving pulse to the liquid, and an i-th (1 ≦ i), wherein a sum of the values is equal to a discharge set value for determining an amount of the liquid to be ejected. ≦ M; 1 ≦ M). The drive pulse generation unit generates the drive pulse based on the divided ejection signal, wherein the drive pulse separates a continuous pulse train for a predetermined period by a positive integer. The i-th divided ejection signal obtained as a positive integer by division by the method
An i-th modulus pulse train obtained by repeating only the quotient of, and an i-th residue pulse train based on the i-th residue obtained by the division by separating the i-th modulus pulse train from the predetermined period. Liquid discharge drive device. 2. The liquid ejection driving device according to claim 1, further comprising a conversion table indicating a relationship between a pulse generation state of the driving pulse and the ejection signal. 3. An i-th separation circuit that divides the i-th divided ejection signal by the modulus to obtain the i-th quotient and the i-th remainder, and outputs the i-th modulus pulse train. An i-th modulating pulse train generating circuit; and an i-th modulating pulse train generating circuit that outputs the i-th modulating pulse train. The driving pulse generator includes the i-th modulating pulse train and the i-th modulating pulse train. 2. The liquid ejection driving device according to claim 1, wherein the driving pulse is generated by combining the driving pulses. 4. The liquid ejection driving device according to claim 1, wherein the i-th residue pulse train is composed of pulses obtained by repeatedly generating the value of the i-th residue. 5. The i-th residue pulse train is obtained by repeatedly generating the value of the i-th modulus, and calculates a duty based on a ratio of the value of the i-th residue to the value of the i-th modulus. 2. The liquid ejection driving device according to claim 1, comprising a pulse having the following. 6. A dividing circuit which receives the ejection set value and generates the first to j-th (1 <j ≦ Q; 1 <Q) ejection signals, wherein the j-th normal pulse train is 6. The liquid ejection driving device according to claim 1, wherein a period corresponding to one pixel is T0, and generation of a pulse starts at time (j-1) .T0 / Q. 7. The liquid ejection driving device according to claim 6, wherein said Q is variable in said division circuit. 8. The liquid ejection driving device according to claim 7, wherein said Q is variable during printing. 9. The apparatus according to claim 1, further comprising a conversion circuit configured to convert the gradation of an image having a predetermined dynamic range so as to match the dynamic range of the liquid discharge driving device and generate the discharge set value. A liquid discharge drive device according to claim 8. 10. A liquid ejection drive device for driving a liquid ejection unit that ejects the liquid by applying vibration based on a drive pulse to the liquid, comprising: a drive pulse generation unit that generates the drive pulse train; The pulse train is based on a modulus pulse train obtained by repeating a pulse train continuous by a modulus value that is a positive integer for a predetermined period and repeating the discharge quotient value, and a discharge pulse value separated from the modulus pulse train by the predetermined period. The discharge quotient is obtained by performing a first conversion on a quotient that is a positive integer obtained by dividing image information having a value that determines a liquid discharge amount by a method that is a positive integer. A liquid ejection drive device having a value obtained by performing a second conversion on the remainder obtained by the division. 11. A separation circuit for obtaining the quotient and the remainder, a conversion circuit for obtaining the ejection quotient and the ejection remainder, a normal pulse train generating circuit for outputting the normal pulse train, and a remainder for outputting the remainder pulse train. The liquid ejection driving device according to claim 10, further comprising a pulse train generation circuit, wherein the drive pulse generation unit generates the drive pulse train by combining the normal pulse train and the residual pulse train. 12. The liquid ejection driving device according to claim 10, further comprising a conversion table indicating a relationship between a generation state of the driving pulse and the image information. 13. The liquid ejection driving device according to claim 10, wherein the remainder pulse train is composed of pulses repeatedly generated by the value of the remainder. 14. The liquid ejection device according to claim 10, wherein the remainder pulse train is obtained by repeatedly generating the modulus value, and includes a pulse having a duty based on a ratio of the remainder value to the modulus value. Drive. 15. The liquid ejection driving device according to claim 1, wherein a period of the pulse in the pulse train is variable. 16. The liquid ejection driving device according to claim 1, wherein the predetermined period is variable. 17. The liquid ejection driving device according to claim 1, wherein the method is variable. 18. A liquid ejecting section for applying vibration based on a driving pulse to a liquid to discharge the liquid, a burst generating circuit for generating a burst signal in which a predetermined number of continuous pulse trains are obtained at a predetermined time interval, and A drive pulse generating unit that generates the drive pulse by controlling a duty of the burst signal based on a discharge set value that determines a discharge amount of the liquid. 19. The duty of the drive pulse is:
19. The liquid ejection driving device according to claim 18, wherein the liquid ejection driving device is constant in each of the continuous pulse trains. 20. The duty of the drive pulse,
20. Increasing sequentially except at 0%.
The liquid discharge drive device according to any one of the preceding claims. 21. The duty of the drive pulse is:
19. The liquid ejection driving device according to claim 18, wherein the pulses included in each of the continuous pulse trains are different. 22. The duty of the drive pulse is 0.
% Or a fixed value larger than 0% and smaller than 100%, and the discharge set value is divided by the predetermined number to obtain the number of quotients obtained as a positive integer. In the pulse train, all the duties of the pulse train included in each of the pulse trains take the fixed value. One of the pulse trains includes,
Dividing the discharge set value by the predetermined number, taking the duty of the fixed value by the number of remainders obtained as a positive integer, the pulse trains other than the pulse train of the quotient and the one pulse train are: 19. The liquid ejection driving device according to claim 18, wherein all the duties of the pulse trains included in each of them are 0%. 23. A liquid discharge section for applying a vibration based on a drive pulse to a liquid to discharge the liquid, a burst generating circuit for generating a burst signal in which a predetermined number of continuous pulse trains are obtained at a predetermined time interval, and A drive pulse generating unit that generates the drive pulse by controlling the amplitude of the burst signal based on a discharge setting value that determines a discharge amount of the liquid. 24. The driving pulse according to claim 23, wherein the amplitude of the driving pulse is constant in each of the continuous pulse trains.
The liquid discharge drive device according to claim 1. 25. The liquid discharge driving device according to claim 23, wherein the amplitude of the driving pulse is different in a pulse included in each of the continuous pulse trains. 26. The liquid ejection driving device according to claim 25, wherein the amplitude of the driving pulse includes 0.