CN100421949C

CN100421949C - Inkjet printer with printing head ejecting ink in line

Info

Publication number: CN100421949C
Application number: CNB2005100893784A
Authority: CN
Inventors: 坂井田惇夫; 铃木克明
Original assignee: Brother Industries Ltd
Current assignee: Brother Industries Ltd
Priority date: 2004-08-05
Filing date: 2005-08-05
Publication date: 2008-10-01
Anticipated expiration: 2025-08-05
Also published as: CN1733483A; JP2006044111A; CN100421948C; CN100408338C; JP4517766B2; CN1733486A; CN1733485A

Abstract

A line head inkjet printer includes an inkjet head, a storage unit, and a controller. The controller generates n kinds waveforms with differnt ink quantity injected from the nozzle (3<=n (natural number)). The storage unit is aim at the combination of m kinds waveforms selected from n kinds waveforms of each region block including at least one nozzle (2<=m (natural number)<=n-1). When the printer processes grayscale printing using m kinds waveforms selected from the n kinds waveforms, the difference of the aspect of the ink injecting amount of each nozzle between these blocks is smaller than the difference of the same combination using m kinds waveforms aimed at the all blocks under the condition of using the combination of the storaged M kinds waveforms aimed at each region block.

Description

The line head ink-jet printer

Technical field

The present invention relates to a kind of China ink that from nozzle, ejects to form the line head ink-jet printer of image.

Background technology

Ink gun comprises nozzle that is used for ink-jet in a large number and the black flow channel that is connected with these nozzles respectively.These black flow channels comprise the pressure chamber that is used to produce ink-jet pressure.By spraying desired China ink amount to print media, thereby can on print media, form image from nozzle.In this ink gun, the ink ejection amount of each nozzle can be along with in variations such as the dimensional accuracy of flow channel unit and assembly precisions.Can cause the density unevenness in the image that is being formed on the print media to spare property in this variation aspect the ink ejection amount.Correspondingly, known have a kind of like this technology, wherein: estimate the China ink amount that ejects from print result, thereby produce checking list from each nozzle; And when printing, use this checking list with the ink ejection amount of independent each nozzle of correction (referring to US5,528,270 and US5,946,006).Therefore, the variation aspect ink ejection amount between the nozzle can be suppressed at reliably, thereby the even property of density unevenness in the image that is formed on the print media can be reduced in effectively.

Summary of the invention

According to above-mentioned technology, respectively all nozzles are proofreaied and correct to deal with among all nozzles in the variation aspect the ink ejection amount.Because the line ink-jet printer has the nozzle of Duoing than the serial ink-jet printer,, print production capacity decline so that make so the amount of calculation that is used to proofread and correct becomes so greatly.

In addition, be printed in the ink gun of the line head ink-jet printer that forms image on the print media by single therein, because elongate along a direction in the ink-jet zone, thus at the dimensional accuracy of flow channel unit and the tendency of changes aspect the assembly precision in increase.

The invention provides a kind of line head ink-jet printer, in this line head ink-jet printer, can be easy to proofread and correct the variation of the China ink amount that goes out from nozzle ejection.

According to an aspect of the present invention, a kind of line head ink-jet printer comprises ink gun, controller and memory cell.Ink gun comprises flow channel unit and a plurality of single electrode.This flow channel unit is formed with respectively and the nozzle pressure chambers communicating.Single electrode is arranged to corresponding with pressure chamber respectively.Controller produces and is used for ejecting the n kind waveform that different China inks are measured respectively from nozzle, and wherein n is equal to or greater than 3 natural number.This memory cell is selected from the combination of the m kind waveform of described n kind waveform at each block stores that comprises at least one nozzle, and wherein m is natural number and 2≤m≤n-1.When the m kind waveform that is selected from described n kind waveform in use when printer carries out gray level printing, in the situation of the combination of using the m kind waveform of being stored at each block, between these blocks in the difference aspect the ink ejection amount of each nozzle less than the difference in the situation of a like combinations using m kind waveforms at all blocks.Select the waveform that is used for each block in the combination of this controller according to the described m kind waveform of gradation data from be stored in memory cell of input, thereby selected waveform is exported to the single electrode of each block.

According to this structure, be used for the waveform combination of each block by change, thereby can be easy to when gray level printing, proofread and correct the variation aspect the ink ejection amount of each nozzle among these blocks.Therefore, can print the high quality image that does not have the even property of density unevenness, can make simultaneously and print the production capacity maintenance efficiently.

According to another aspect of the present invention, a kind of line head ink-jet printer comprises ink gun, form stores unit and controller.Ink gun comprises flow channel unit and a plurality of single electrode.This flow channel unit is formed with respectively and the nozzle pressure chambers communicating.Described single electrode is arranged to corresponding with described pressure chamber respectively.The form stores unit stores a form, and a plurality of blocks are according to the ink ejection amount classification of each nozzle in each block in this form, and each block all comprises at least one nozzle in these blocks.Controller produces and is used for ejecting the n kind waveform that different China inks are measured respectively from nozzle, and wherein n is equal to or greater than 3 natural number.When the m kind waveform that is selected from described n kind waveform in use when printer carries out gray level printing, wherein m is natural number and 2≤m≤n-1, controller is determined the combination of m kind waveform at each block, make in the situation of the combination of using determined m kind waveform at each block, between these blocks in the difference aspect the ink ejection amount of each nozzle less than the difference in the situation of a like combinations using m kind waveforms at all blocks.Controller is with the determined combination storage afferent echo shape memory cell that is used for the m kind waveform of each block.Select the waveform that is used for each block in the combination of this controller according to the described m kind waveform of gradation data from be stored in the waveform memory cell of input, thereby selected waveform is exported to the single electrode of each block.

According to this structure, suitably change waveform combination by changing, thereby can change waveform combination at each block according to printing environment.Therefore, can be easy to proofread and correct the variation aspect the ink ejection amount of each nozzle among these blocks when gray level printing.

The N-1 bar dummy line that ink gun can be extended by the throughput direction along print media is divided into N block, and wherein N represents to be equal to or greater than 2 natural number.According to this structure, can be limited in ink ejection amount with respect to the length direction of ink gun effectively and change image quality is applied big adverse effect.

These dummy line can be by the structural change point that extends along the direction vertical with throughput direction in ink gun.For example, ink gun can also comprise a plurality of actuating units.These actuating units have trapezoidal shape.Each actuating unit comprises piezoelectric patches, common electrode and described single electrode.Piezoelectric patches extends in described pressure chamber.Common electrode and single electrode are clipped in piezoelectric patches between them.Each described single electrode is arranged on the piezoelectric patches and is corresponding with each pressure chamber on the position.These actuating units are arranged on the flow channel unit, make the hypotenuse of adjacent actuators unit overlapped when throughput direction is observed.Every dummy line intersects at the hypotenuse of described each each actuating unit of structural change point place and the minor face of each actuating unit by each structural change point.According to this structure, so owing to this structure of ink gun can be proofreaied and correct more fully.

Description of drawings

Fig. 1 is for having used the schematic diagram of printer of method that is used to proofread and correct ink ejection amount according to first embodiment of the invention on it;

Fig. 2 is the plane at one of them head main body shown in Fig. 1;

Fig. 3 serves as reasons at the enlarged drawing of the line of the single-point shown in Fig. 2 area surrounded;

The cutaway view of Fig. 4 for cutting open along the IV-IV line in Fig. 3;

Fig. 5 A and 5B are the enlarged drawing at one of them actuating unit shown in Fig. 2;

Fig. 6 is the functional-block diagram at the controller shown in Fig. 1;

Fig. 7 is the functional-block diagram that divides in the print control section shown in Fig. 6;

Fig. 8 is a plane, demonstrates the ink-jet zone in one of them head main body shown in Fig. 1;

Fig. 9 is the view that is used for measuring the system architecture of the China ink amount that goes out from the nozzle ejection at each block shown in Fig. 8;

Figure 10 demonstrates the improvement embodiment of the system architecture that is used for measuring the China ink amount that goes out from the nozzle ejection at each block shown in Fig. 8;

Figure 11 is the view of method that is used to proofread and correct ink ejection amount that is used for illustrating according to second embodiment of the invention;

Figure 12 is the functional-block diagram according to the controller 100 of the 3rd embodiment;

Figure 13 for number of grayscale levels m be 3 and waveform patterns kind number n be the embodiment of 4 o'clock waveform patterns; And

Figure 14 is the functional-block diagram according to the controller 100 of an improvement embodiment.

The specific embodiment

With reference to these accompanying drawings first embodiment of the present invention is described below.

At first the printer of having used on it according to the method for the correction ink ejection amount of first embodiment of the invention is described with reference to Fig. 1.At the printer shown in Fig. 11 is the line head color inkjet printer, and it has four fixing ink guns 2, and each ink gun is configured as along the narrow and long rectangular of the direction elongation vertical with the paper that demonstrates Fig. 1 with plane.In Fig. 1, printer 1 has the paper feed unit 14 that is located in its underpart, be located at the splicing part 16 in its top and be located at supply unit 20 in its middle part.Printer 1 also has the controller 100 (referring to Fig. 6) of the operation that is used to control printer 1.

Paper feed unit 14 has a paper storage part 15 and a paper feed roller 45.Stacked rectangle print paper P can leave in the paper storage part 15 mutually.Paper feed roller 45 connects a ground with one of print paper P and presents towards supply unit 20 according to presenting a kind of like this mode towards supply unit 20 at the print paper P in the paper storage part 15.Print paper P leaves in the paper storage part 15, thereby can present these paper P along the direction parallel with the long limit of every paper P.Two couples of feed roller 18A, 18B, 19A and 19B are arranged between paper storage part 15 and the supply unit 20 along transfer passage.A printing paper P who presents out from paper feed unit 14 is upwards carried among Fig. 1 as front end with the minor face of this printing paper P by feed roller 18A and 18B, is carried towards supply unit 20 left by feed roller 19A and 19B then.

The rotating shaft of paper feed roller 45 tilts 3 ° with respect to the direction vertical with the inwall (not shown) of paper storage part 15, thereby this rotating shaft is along with its more close supply unit 20 that becomes away from inwall.For this reason, this printing paper P that is picked up by paper feed roller 45 advances along the direction that the inwall with paper storage part 15 tilts a little, thereby forces the inwall of the long limit of this printing paper P near paper storage part 15.The inwall of paper storage part 15 is parallel to the throughput direction of this printing paper P with supply unit 20.Before the minor face of this printing paper P arrived feed roller 18A and 18B, the long limit of this printing paper P was resisted against on the inwall of paper storage part 15.Then, when the long limit of this printing paper P was resisted against on the inwall of paper storage part 15, this printing paper P advanced towards feed roller 18A and 18B along the inwall of paper storage part 15.By making the inwall inclination so a kind of simple structure of paper feed roller 45 with respect to paper storage part 15, the skew that can proofread and correct this printing paper P can be guaranteed this printing paper of continuous feeding P simultaneously.This printing paper P that by feed roller 18A and 18B clamping presents out towards supply unit 20 by feed roller 19A and 19B.

Two leather belt rollers 6 and 7 that supply unit 20 has an annular belt conveyor 11 and twined by this belt conveyor 11.Regulate the length of belt conveyor 11, thereby in the belt conveyor 11 that is wrapped between two leather belt rollers 6 and 7, produce predetermined tension force.By belt conveyor 11 is wrapped between two leather belt rollers 6 and 7, thereby form two planes on belt conveyor 11, these two planes comprise the common tangent of leather belt roller 6 and 7 respectively and are parallel to each other.Be used as the feed surface 27 of this printing paper P in these two planes facing to a plane of ink gun 2.When ink gun 2 printed the upper surface of this printing paper P, this printing paper P that presents out from paper feed unit 14 carried at the feed surface 27 of belt conveyor 11.Afterwards, this printing paper P arrives splicing part 16.In this splicing part 16, the print paper P that has carried out printing is stacked mutually.

Each ink gun of four ink guns 2 has a head main body 13 at its lower end.The same as hereinafter described, this head main body 13 has a flow channel unit 4 (referring to Fig. 4) and bond to actuating unit 21 on this flow channel unit 4.In flow channel unit 4, be formed with a large amount of independent black flow channel 32 that comprises with nozzle 8 pressure chambers communicating 10.Actuating unit 21 can be exerted pressure to the China ink in desired pressure chamber 10.

Each head main body 13 is shaped as and is similar to cuboid, and it extends along the direction vertical with the paper that demonstrates Fig. 1 with plane.Four head main body 13 are provided with along the left and right directions in demonstrating the paper of Fig. 1 is close mutually.In each bottom surface (ink-jet zone) of four head main body 13, be formed with the very little nozzle of a large amount of diameters 8 (referring to Fig. 2).The black color that ejects from each nozzle 8 is any magenta (M), yellow (Y), cyan (C) and the black (K).It is identical being subordinated to the black color that the big flow nozzle 8 of a head main body 13 ejects.Be subordinated to eject respectively in a large amount of discharging opening for permitting discharging of the toner of four head main body 13 have the magenta of being selected from, the dissimilar China ink of the color of Huang, green grass or young crops and black four kinds of colors.

Between the feed surface 27 of the bottom surface of each head main body 13 and belt conveyor 11, be formed with a minim gap.Print paper P carries in Fig. 1 from right to left along the transfer passage that passes this gap.When this printing paper P successively four head main body 13 below by the time, the upper surface towards this printing paper P sprays China ink from nozzle 8 according to view data, forms desired coloured image thus on this printing paper P.

The sticking silicon rubber of external peripheral surface 11A apparatus of belt conveyor 11 is handled.Therefore, when a leather belt roller 6 is rotated counterclockwise (along the direction of the arrow A in Fig. 1), supply unit 20 can be carried the print paper P that is presented by feed roller 18A, 18B, 19A and 19B towards splicing part 16, utilize the viscosity of external peripheral surface 11A that print paper P is remained on the external peripheral surface 11A of belt conveyor 11 simultaneously.

Two leather belt rollers 6 contact with the inner circumferential surface 11B of belt conveyor 11 with 7.In two leather belt rollers 6 and 7 of this supply unit 20, the leather belt roller 6 that is positioned on the downstream of transfer passage is connected with carrying motor 74.Control according to controller 100 drives this conveying motor 74 rotations.Another leather belt roller 7 is a driven voller, and it rotates along with the rotation of leather belt roller 6 under the revolving force effect that is provided by belt conveyor 11.

Mip rolls 38 and 39 is arranged near the leather belt roller 7, thereby belt conveyor 11 is clamped between mip rolls 38 and 39.Mip rolls 38 and each roller of 39 have a body, and the axial length of its length and leather belt roller 7 about equally and can freely rotate.Push this mip rolls 38 downwards by unshowned spring, thereby the print paper P that presents to supply unit 20 can be pressed on the feed surface 27.Because mip rolls 38 and 39 and belt conveyor 11 cooperation clamp print paper P, institute so that this printing paper P reliably attached on the feed surface 27.

In Fig. 1, on the left side of supply unit 20, be provided with one and take off cardboard 40.This right-hand member that takes off cardboard 40 enters between print paper P and the belt conveyor 11, breaks away from feed surface 27 thereby make attached to the print paper P on the feed surface 27 of belt conveyor 11.

Two couples of feed roller 21A, 21B, 22A and 22B are arranged between supply unit 20 and the splicing part 16.As in the leading edge, the print paper P that discharges from supply unit 20 upwards carries among Fig. 1 by feed roller 21A and 21B and presents to splicing part 16 by feed roller 22A and 22B at the minor face of this printing paper P.

As shown in Figure 1, be provided with as the paper sensor 33 that comprises the optical pickocff of photocell and light receiving element at mip rolls 38 with between the ink gun 2 on the upstream side.Paper sensor 33 is configured such that photocell towards the emission of the detection position on transfer passage light, and makes light receiving element receive reverberation.Represent to depend on the difference on intensity of reflected light that has/lack print paper P from the signal level of paper sensor 33 outputs in inspection positions.That is to say that the leading edge of print paper P arrives the detection position in the moment that output signal level increases rapidly.Because can find that the leading edge of print paper P arrives in the detection position, so print signal is offered ink gun 2 according to this moment according to the output signal of paper sensor 33.

With reference to Fig. 2 and 3 each head main body 13 is elaborated below.Fig. 2 is the plane at one of them head main body 13 shown in Fig. 1.The serve as reasons amplification view of the single-point line area surrounded in Fig. 2 of Fig. 3.Shown in Fig. 2 and 3, head main body 13 has a mobile channel unit 4, is formed with a large amount of pressure chamber 10 and the big flow nozzle 8 of decomposition pressure chamber group 9 in this flow channel unit 4.The trapezoidal actuating unit 21 that zig zag is arranged on two rows is bonded on the upper surface of flow channel unit 4.More particularly, each actuating unit 21 is arranged so that the length direction layout of the parallel relative side (side up and down) of actuating unit 21 along flow channel unit 4.The hypotenuse of adjacent actuators unit 21 is overlapped along the width of flow channel unit 4.

The lower surface corresponding with the bonding region of actuating unit 21 on the position of flow channel unit 4 is used as the ink-jet zone.As shown in Figure 3, big flow nozzle 8 with the arranged in form of matrix in the surface in ink-jet zone.With 10 one-tenth matrix arrangement of respective nozzle 8 pressure chambers communicating.The a plurality of pressure chamber 10 of the lower surface corresponding with the bonding region of an actuating unit 21 on the position that are arranged in flow channel unit 4 form pressure chamber's group 9.

Each nozzle 8 is communicated with sub-manifold 5A for conical nozzle and by pressure chamber 10 and the hole 12 that has diamond shaped in plane.Sub-manifold 5A is as the flow channel that goes out from manifold 5 bifurcateds.Manifold 5 has opening portion 5B, and these opening portions 5B is located in the upper surface of flow channel unit 4 and is connected to unshowned black flow pass.Provide China ink from unshowned ink container to flow channel unit 4 by this China ink flow pass.By the way, in order to be more readily understood these accompanying drawings, in Fig. 2 and 3, pressure chamber 10 (pressure chamber's group 9), opening portion 5B and the hole 12 that should be depicted as those owing to be positioned at each actuating unit 21 below dotted line are depicted as solid line.

With reference to Fig. 4 the cross-section structure of each head main body 13 is elaborated below.The cutaway view of Fig. 4 for cutting open along the IV-IV line in Fig. 3.As shown in Figure 4, head main body 13 is wherein flow channel unit 4 and actuating unit 21 mutual bonding products (referring to Fig. 2).Flow channel unit 4 has a laminar structure, wherein cavity plate 22, substrate 23, hole plate 24, feeding plate 25, and

manifold plate

26,27 and 28, cover plate 29 and nozzle plate 30 are laminated together according to descending.

Cavity plate 22 is the metallic plate with hole of the approximate rhombus that forms pressure chamber 10 in a large number.Substrate 23 is a metallic plate, and it has each and is used for that all a pressure chamber 10 is connected a large amount of connecting holes on the corresponding hole 12 and each and all is used for pressure chamber 10 is connected a large amount of connecting holes on the respective nozzle 8.Hole plate 24 is a metallic plate, and it has the hole that forms hole 12 in a large number and each and all is used for a pressure chamber 10 is connected a large amount of connecting holes on the respective nozzles 8.Feeding plate 25 is a metallic plate, and it has each and is used for that all a hole 12 is connected a large amount of connecting holes on the corresponding sub-manifold 5A and each and all is used for pressure chamber 10 is connected a large amount of connecting holes on the respective nozzle 8.Manifold

plate

26,27 and 28 is a metallic plate, and they have the hole that forms sub-manifold 5A and each and all are used for a pressure chamber 10 is connected a large amount of connecting holes on the respective nozzle 8.Cover plate 29 is a metallic plate, and it has each and all is used for a pressure chamber 10 is connected a large amount of connecting holes on the respective nozzles 8.Nozzle plate 30 is a metallic plate, and it has the nozzle 8 that is formed in a large number wherein.These 22 to 30 whiles laminated together of nine blocks of plates aim at mutually, thereby form independent black flow channel 32.

Next with reference to Fig. 5 A and 5B the structure of each actuating unit 21 is described.Fig. 5 A is a local amplification view, demonstrates actuating unit 21 and pressure chamber 10.Fig. 5 B is a plane, demonstrates the shape that is formed on the single electrode on the actuating unit 21.

Shown in Fig. 5 A, actuating unit 21 has laminar structure, and wherein lamination has four

piezoelectric patches

41,42,43 and 44.These piezoelectric patches 41 to 44 form has the equal thickness that is approximately 15 μ m.Piezoelectric patches 41 to 44 is continuous flat board (continuous flat layer), and they are arranged in above a large amount of pressure chamber 10 that are formed in the ink-jet zone.Each piezoelectric patches 41 to 44 is made by having ferroelectric ceramic material based on lead zirconate titanate (PZT).

On piezoelectric patches 41, be formed with on the position single electrode 35 corresponding with each pressure chamber 10 as the superiors.Be inserted with the common electrode 34 of thick about 2 μ m between as the piezoelectric patches 41 of the superiors and piezoelectric patches 42, thereby this common electrode 34 is formed on the whole surface of these piezoelectric patches at the downside of the superiors.By the way, between piezoelectric patches 42 and piezoelectric patches 43, any electrode is not set.Each electrode of single electrode 35 and common electrode 34 by metal material for example AG-PD make.

Shown in Fig. 5 B, single electrode 35 thickness are about 1 μ m, and have and in the shape of the pressure chamber shown in Fig. 3 10 similar rhombus flat shape roughly.One of them acute angle portion of this rhombus single electrode 35 extends out.Be provided with the circular pad part 36 that diameter is about 160 μ m and is electrically connected with single electrode 35 at the elongated end place of rhombus single electrode 35.For example, this pad portion 36 is made by the glass dust that contains gold.Shown in Fig. 5 A, this pad portion 36 is bonded on the surface of extension of single electrode 35.

Common electrode 34 is ground connection in unshowned zone.Therefore, this common electrode 34 remains on the earth potential place comparably in the zone corresponding with all pressure chamber 10.But single electrode 35 is electrically connected with the unshowned driver 1C that is provided as the part of controller 100 separately, thereby can selectively control current potential at each pressure chamber 10.

Next will the method that be used for drive actuator unit 21 be described.The polarised direction of the piezoelectric patches 41 in actuating unit 21 is the thickness direction of piezoelectric patches 41.That is to say, actuating unit 21 has so-called single piezo crystals chip structure, wherein at a piezoelectric patches of upside (promptly away from pressure chamber 10) as the layer that comprises working portion, and three piezoelectric patches 42 to 44 that are positioned at downside (promptly near pressure chamber 10) are used as the inoperative part.Therefore, when the potential setting of single electrode 35 during at predetermined plus or minus numerical value place, the electric field applying portion that is located at the piezoelectric patches 41 between the electrode is used as working portion, and shrinks along the direction vertical with polarised direction under the effect in piezo-electric traverse effect under the direction of an electric field situation identical with polarised direction.On the other hand, piezoelectric patches 42 to 44 can not be subjected to electric field effects, thereby piezoelectric patches 42 to 44 can spontaneously not shrink.Therefore, between the piezoelectric patches 41 of upside and piezoelectric patches 42 to 44, producing, thereby the integral body of piezoelectric patches 41 to 44 is according to be out of shape (single piezoelectric chip distortion) in the mode of non-working side convex-shaped bending in the difference in the distortion of the direction vertical with polarised direction at downside.In this case, shown in Fig. 5 A, the lower surface of piezoelectric patches 41 to 44 is fixed on the upper surface of the cavity plate 22 that defines pressure chamber.Therefore, piezoelectric patches 41 to 44 is according to being out of shape towards the mode of pressure chamber's side convex bending.In this case, press thereby the volume of pressure chamber 10 reduce to increase China ink, thus from nozzle 8 that this pressure chamber 10 is connected eject China ink.Then, when the current potential of single electrode 35 turned back to the identical numerical value of current potential with common electrode 34, these piezoelectric patches 41 to 44 returned to original-shape, thereby the volume of pressure chamber 10 is got back to raw value.Therefore, from manifold 5 sides suction China ink.

Actual driving process is as follows.That is to say that the potential setting with each single electrode 35 is the current potential (being referred to below as high potential) that is higher than common electrode 34 in advance.No matter when produce the request of injection, just the current potential with single electrode 35 changes over the current potential (be referred to below as electronegative potential) identical with the current potential of common electrode 34, changes over high potential again in predetermined timing place then.Therefore, become moment of electronegative potential at the current potential with single electrode 35, these piezoelectric patches 41 to 44 return to original-shape, thereby the volume of pressure chamber 10 is compared increase (wherein two electrodes differ from one another) on current potential with original state.In this case, apply negative pressure, thereby China ink is drawn into the pressure chamber 10 from manifold 5 sides to the inside of pressure chamber 10.Then, these piezoelectric patches 41 to 44 when the current potential of single electrode 35 becomes high potential again according to being out of shape towards the mode of pressure chamber's 10 convex bendings.Therefore, the volume of pressure chamber 10 reduce so that pressure chamber's 10 pressure inside become on the occasion of, thereby increased black pressure, eject ink droplet thus.That is to say, provide pulse based on high potential to eject ink droplet to single electrode 35.It is desirable to, the width of pulse equals AL (Acoustic Length wave length of sound), and this length is pressure wave time span when manifold 5 propagates into nozzle 8 in pressure chamber 10.According to this process, when the inside of pressure chamber 10 when negative pressure state turns back to barotropic state, then two pressure are merged into a strong pressure, can eject ink droplet thus.

As for gray level printing, the China ink amount (volume) of promptly regulating based on the number of times that ejects ink droplet from nozzle 8 by the number of ink droplets that ejects from nozzle 8 realizes the gray scale performance.Therefore, from the nozzle 8 corresponding, carry out showing the ink-jet of corresponding number of times continuously with specified gray scale with specified ink dot zone.In general, when carrying out ink-jet continuously, preferably, providing the distance between the pulse that is used for spraying ink droplet to equal AL.Like this, the pressure of the pressure that produced when spraying ink droplet in the back the residual pressure wave period of the pressure that is produced when ejecting ink droplet in front is consistent wave period, thereby can make these pressure waves stacked pressure that is used to spray these ink droplets with increase mutually.

Then controller 100 is elaborated with reference to Fig. 6.Fig. 6 is the functional-block diagram of controller 100.This controller 100 comprises: CPU (CPU), as processor; ROM (read-only storage) is used for storing by the program of CPU execution with in the used data RAM of these programs (random access memory), is used for temporarily storing when these programs of execution data; And driver IC, be used for drive actuator unit 21.These building block co-operatings make funtion part described below to work.

Controller 100 is operated according to the instruction that provides from personal computer (PC) 200.As shown in Figure 6, controller 100 comprises that on function communications portion 141, operation control section 142 and print control section divide 143.By the way, each funtion part is by for example ASIC (special IC) realization of hardware.All these funtion parts can be realized by software by software realization or partial function part.

Communications portion 141 is communicated by letter with PC200.Operation control section 142 is exported in the instruction relevant with operation that this communications portion 141 will send out from PC200.The instruction relevant with printing that communications portion 141 will send out from PC200 exported to print control section and divided 143.Operation control section 142 divides the 143 instruction controls that provide to carry motor 74 etc. according to the instruction that provides from PC200 with from print control section.Print control section divides 143 according to the instruction execution printing relevant with printing that provides from PC200.

Then be elaborated to printing control section 143 with reference to Fig. 7.Fig. 7 divides 143 functional-block diagram for print control section.As shown in Figure 7, print control section divides 143 to have six pulses generation part 144a to 144f, a correction coefficient storage area 148, a mapping table storage area 149 and waveforms selection parts 150.

Pulse produces part 144a to 144f and produces the pulse with six kinds of mutual different waveform patterns.In this embodiment, can enough three gray levels (not comprising the situation of injection) carry out gray level printing.Can realize gray level printing according to ejecting volume different mutually little, a kind of like this mode of the big ink droplet of neutralization.These gray levels in gray level printing will be represented as little ink droplet, middle ink droplet and big ink droplet below.As for six kinds of waveform patterns, for each gray level provides two kinds of patterns.Also add three codes (001 to 110) so that specify these waveform patterns respectively to these six waveform patterns.Table 1 demonstrates the example of these six kinds of waveform patterns.

Table 1

Waveform patterns	Code
Waveform patterns	Code	Little ink droplet 1	001
Little ink droplet 2	010	Little ink droplet 1	001
Little ink droplet 2	010	Middle ink droplet 1	011
Middle ink droplet 2	100	Middle ink droplet 1	011
Middle ink droplet 2	100	Big ink droplet 1	101
Big ink droplet 2	110	Big ink droplet 1	101

As shown in the table 1, waveform patterns 001 and 010 both are provided for forming little ink droplet.Produce waveform patterns 001 and 010, make ink ejection amount in using waveform patterns 010 greater than the ink ejection amount in using waveform patterns 001.Ink droplet during waveform patterns 011 and 100 boths are provided for forming.Produce waveform patterns 011 and 100, make ink ejection amount in using waveform patterns 100 greater than the ink ejection amount in using waveform patterns 011.Waveform patterns 101 and 110 boths are provided for forming big ink droplet.Produce waveform patterns 101 and 110, make ink ejection amount in using waveform patterns 110 greater than the ink ejection amount in using waveform patterns 101.By the way, be used to form the ink ejection amount of little ink droplet less than ink droplet in being used to form and the ink ejection amount that is used to form big ink droplet.The ink ejection amount of ink droplet is also less than the ink ejection amount that is used to form big ink droplet in being used to form.

Pulse produces part 144a and produces the pulse with waveform patterns 001.Pulse produces part 144b and produces the pulse with waveform patterns 010.Pulse produces part 144c and produces the pulse with waveform patterns 011.Pulse produces part 144d and produces the pulse with waveform patterns 100.Pulse produces part 144e and produces the pulse with waveform patterns 101.Pulse produces part 144f and produces the pulse with waveform patterns 110.

The correction coefficient that correction coefficient storage area 148 is set each gray level in each block is stored with the form of correction coefficient table, and each block is defined as at least one nozzle 8 that includes in the ink-jet zone of head main body 13.Each correction coefficient is provided for giving each block classification according to the ink ejection amount of each nozzle 8 in each block.Ratio according to the desirable ink ejection amount of the ink ejection amount of each nozzle 8 in each block and a nozzle 8 is determined each correction coefficient.The same as hereinafter described, in the process of producing head main body 13, in the step of proofreading and correct ink ejection amount, determine this correction coefficient.Optionally, can determine correction coefficient as follows, promptly by the ink ejection amount of each block of sensor measurement that provides in the printer 1.Because proofread and correct the China ink amount that from the nozzle each block 8, ejects, so can make among these blocks the difference aspect the ink ejection amount of each nozzle 8 less according to this correction coefficient.Specifically, if controller 100 is controlled ink-jet by using correction coefficient, then among these blocks, do not use the situation of these correction coefficient little in the diversity ratio aspect the ink ejection amount of each nozzle 8.

Fig. 8 demonstrates the embodiment that block is set.Fig. 8 is a plane, demonstrates the ink-jet zone in head main body 13.Zone corresponding with each actuating unit 21 on the position is illustrated by the broken lines.These area limitings corresponding pressure chamber group 9 and its shape be similar to trapezoidal.In the respective regions that defines pressure chamber's group 9, be formed with big flow nozzle 8 (referring to Fig. 2 and 3).As shown in Figure 8, the ink-jet zone is divided into nine block A to I by eight dummy line that the throughput direction along print paper P extends.Every the dummy line process will define the trapezoidal hypotenuse of pressure chamber's group 9 and the summit that this trapezoidal minor face links together.That is to say that these dummy line are set for and made these dummy line pass through along the structural change point of the head main body 13 of the direction extension vertical with throughput direction.In other words, at least one block (block C, E and G in Fig. 8) is included in the whole borderline region between two adjacent actuators unit 21.In Fig. 8, the borderline region between two adjacent actuators unit 21 is the parallelogram zone that the hypotenuse by two adjacent actuators unit 21 limits.Table 2 demonstrates and embodiment at the corresponding correction coefficient table of the block A to I shown in Fig. 8.

Table 2

Block	Correction coefficient (being used for little ink droplet)	Correction coefficient (being used for ink droplet)	Correction coefficient (being used for big ink droplet)
Block	Correction coefficient (being used for little ink droplet)	Correction coefficient (being used for ink droplet)	Correction coefficient (being used for big ink droplet)	A	0	0	0
B	0	0	0	A	0	0	0
B	0	0	0	C	0	0	1
D	0	1	1	C	0	0	1
D	0	1	1	E	1	1	1
F	0	1	1	E	1	1	1
F	0	1	1	G	0	0	1
H	0	0	0	G	0	0	1
H	0	0	0	I	0	0	0

As shown in table 2, the block in the ink-jet zone of head main body 13 is by two correction coefficient " 0 " that are used for each gray level and " 1 " classification.Correction coefficient " 0 " represents that the ink ejection amount of each nozzle 8 is standards.Correction coefficient " 1 " represents that the ink ejection amount of each nozzle 8 is less than standard.By the way, can set these correction coefficient by an arbitrary number grade.

Mapping table storage area 149 is arranged so that and makes among block combination in the minimized waveform patterns of difference aspect the ink ejection amount of each nozzle 8 as selecting the mapping table storage with being used in gray level printing that this is to determine at corresponding block and each gray level according to the correction coefficient table that is stored in the correction coefficient storage area 148.Table 3 demonstrates the embodiment of this selection mapping table.

Table 3

Block	Waveform patterns (being used for little ink droplet)	Waveform patterns (being used for ink droplet)	Waveform patterns (being used for big ink droplet)
Block	Waveform patterns (being used for little ink droplet)	Waveform patterns (being used for ink droplet)	Waveform patterns (being used for big ink droplet)	A	001	011	101
B	001	011	101	A	001	011	101
B	001	011	101	C	001	011	110
D	001	100	110	C	001	011	110
D	001	100	110	E	010	100	110
F	001	100	110	E	010	100	110
F	001	100	110	G	001	011	110
H	001	011	101	G	001	011	110
H	001	011	101	I	001	011	101

As shown in table 3 the same, the correction coefficient that will be used for little ink droplet gray scale therein is set in the correction coefficient table that is stored in correction coefficient storage area 148 among the block A to D and block F to I of " 0 ", and the waveform patterns that is used to form little ink droplet gray scale is set at the waveform patterns " 001 " of expression standard ink jet inks amount.On the other hand, the correction coefficient that will be used for little ink droplet gray scale therein is set at the block E of " 1 ", and the waveform patterns that is used to form little ink droplet gray scale is set at waveform patterns " 010 ", this aspect ink ejection amount greater than waveform patterns " 001 ".The correction coefficient that will be used for the ink droplet gray scale therein is set in correction coefficient table among the block A to C and block G to I of " 0 ", and the waveform patterns of ink droplet gray scale is set at waveform patterns " 011 " in being used to form, and this is the standard ink jet inks amount.On the other hand, the correction coefficient that will be used for the ink droplet gray scale therein is set among the block D to F of " 1 ", and the waveform patterns of ink droplet gray scale is set at waveform patterns " 100 " in being used to form, this aspect ink ejection amount greater than waveform patterns " 011 ".The correction coefficient that will be used for big ink droplet gray scale therein is set at correction coefficient table among the block A and B and block H and I of " 0 ", and the waveform patterns that is used to form big ink droplet gray scale is set at the waveform patterns " 101 " of expression standard ink jet inks amount.On the other hand, the correction coefficient that will be used for big ink droplet gray scale therein is set at the block C to G of " 1 ", and the waveform patterns that is used to form big ink droplet gray scale is set at waveform patterns " 110 ", this aspect ink ejection amount greater than waveform patterns " 101 ".Like this, can make in these blocks A to I less in each gray level in the difference aspect the ink ejection amount of each nozzle 8.Specifically, can make in these blocks A to I in the difference aspect the ink ejection amount of each nozzle 8 less than not using correction coefficient table (table 2) and selecting the situation of mapping table (table 3).

Waveform selects part 150 to refer to the selection mapping table that is stored in the mapping table storage area 149, is used in response to the print command that provides from communications portion 141 (expression comprise the block of the nozzle 8 that is required to spray ink droplet and the gradation data that will form) with the definite waveform patterns that will use.Waveform selects part 150 to select the pulse with predetermined waveform patterns among the pulse that is produced by pulse generation part 144a to 144f, selected pulse is offered the corresponding single electrode 35 of actuating unit 21.Therefore, drive actuator unit 21 to be ejecting calibrated ink droplet from respective nozzle 8, thereby forms the ink dot with desired gray scale on print paper P.

Next, will the method that being used to of will carrying out after producing head main body 13 proofreaied and correct ink ejection amount be described.This method that is used for proofreading and correct ink ejection amount is a kind of method that is used for determining as the corresponding correction coefficient of the content of the correction coefficient table that is stored in correction coefficient storage area 148.At first, in each block of block A to I, actual measurement goes out the China ink amount (first step) that ejects from nozzle 8.Fig. 9 demonstrates the ad hoc structure that is used to measure ink ejection amount.As shown in Figure 9, ink supply pipe 111 end is connected with the flow channel unit 4 of the head main body of being produced 13.Another end of ink supply pipe 111 is connected with ink container 110.Therefore, the China ink that is stored in the ink container 110 offers flow channel unit 4 by ink supply pipe 111.The actuating unit 21 of head main body 13 is connected with the measurement controller (not shown) that can drive these actuating units 21.Ink container 110 is placed on the instrument 112 of weighing, thereby can measures the gross weight of ink container 110.

By the way, the structure that is used for the ink ejection amount of gaging nozzle 8 is not limited to said structure.For example, as shown in figure 10, the instrument 112 of weighing can be measured ink ejection amount when head main body 13 is directly injected to ink droplet on the pallet 113 that is located on the instrument 112 of weighing.

In said structure, measure controller drive actuator unit 21 and from the nozzle 8 of each block of block A to I, eject ink droplet.When measuring controller and from the nozzle 8 of each block of block A to I, eject ink droplet, measure before ink-jet and the gross weight of ink container afterwards 110 with the instrument 112 of weighing.Therefore, can measure the China ink amount (the China ink amount of minimizing) that in the process of from the nozzle 8 of each block of block A to I, spraying ink droplet, in ink container 110, consumes, that is to say, can measure the China ink amount that from the nozzle 8 of each block of block A to I, ejects.At each block of block A to I and measure the ink ejection amount (measuring and the corresponding ink ejection amount of a plurality of input signal numerical value) of nozzle 8 at each gray level (little ink droplet, middle ink droplet and big ink droplet).

Then, determine correction coefficient (second step) according to the ink ejection amount of the nozzle of measuring at each block of each gray level and block A to I by said method 8.Specifically, each ink ejection amount of measuring divided by nozzle 8 quantity in corresponding of block A to I, is calculated the ink ejection amount of each nozzle 8 thus.Determine correction coefficient so that between these blocks, minimize in the difference aspect the ink ejection amount of each nozzle 8.For example, the ink ejection amount of each nozzle 8 that calculates when each block at each gray level and block A to I be standard the time, this correction coefficient is defined as " 0 ".On the other hand, when the amount that is calculated during, this correction coefficient is defined as " 1 " less than standard volume.The form of determined correction coefficient with correction coefficient table is stored in the correction coefficient storage area 148.In this case, produce the selection mapping table, and it is stored in the mapping table storage area 149 according to correction coefficient table.

According to above-mentioned first embodiment, because the ink ejection amount for each block of block A to I is measured with the instrument 112 of weighing, so the error that causes owing to the variation on the surface appearance of print paper P can not occur, although when detecting the concentration of print image, this error can occur.Therefore, correction coefficient can be accurately calculated, thereby the even property of density unevenness in the print result can be suppressed at reliably.And, because the instrument 112 of weighing is all simpler than any optical pickocff, so can go out the correction coefficient of ink ejection amount with lower cost calculation.Therefore, can reduce the production cost of head main body 13.

And, because these blocks are divided by the dummy line of extending along the throughput direction of paper P, change image quality is applied big adverse effect so can suppress ink ejection amount with respect to the length direction of head main body 13.

And, because every dummy line is by following summit, this summit is the structural change point in head main body 13, and this summit will define the hypotenuse of trapezoid area of actuating unit 21 and the minor face of this trapezoid area links together, so because this structure of head main body 13 can be made more fully proofreaies and correct.

And, because can when the step of carrying out the one-shot measurement ink ejection amount (first step), determine correction coefficient, so can carry out the measurement of ink ejection amount at short notice.Therefore, can reduce the production cost of printer 1.

And, because correction coefficient determines at each gray level, so can in gray level printing, accurately proofread and correct ink ejection amount.

And, because can measure ink ejection amount, so can measure ink ejection amount at short notice by a kind of like this straightforward procedure of gross weight of measuring ink container 110 with the instrument 112 of weighing.

And, can determine correction parameter, make the ink ejection amount of each nozzle 8 among block A to I, become consistent.By this structure, can further effectively suppress the variation of ink ejection amount.

In addition, according to described in the first embodiment printer 1, because the ink ejection amount of nozzle 8 is by proofreading and correct with reference to the correction coefficient table that is used for block A to I that is stored in correction coefficient storage area 148, so can be easy to proofread and correct the ink ejection amount variation of each nozzle 8 among these blocks A to I.Therefore, can print the high quality image that does not have the even property of density unevenness, can make simultaneously and print the production capacity maintenance efficiently.

According to first embodiment, pulse produces part 144a to 144f and produces the multiple waveform that is used for ejecting different China ink amounts from nozzle 8 at corresponding gray level.Waveform selects part 150 to select the waveform corresponding with gray level that is used for each section from the described multiple waveform that produces at corresponding gray level.Therefore, can print high quality image according to the printer 1 of this embodiment, even wherein in the situation of gray level printing, also suppressed the variation aspect the ink ejection amount of each nozzle between these blocks.

In addition, in the first embodiment, mapping table storage area 149 stores the correction coefficient table that is used for each gray level.Therefore, even in the situation of gray level printing, also can suppress the variation aspect the ink ejection amount of each nozzle between these blocks.

And, suitably change according to environmental change if be stored in content in the correction coefficient table, then can be suppressed at the variation aspect the ink ejection amount of each nozzle 8 among these blocks A to I reliably.

Environment (for example temperature) variation can cause the variation of the China ink amount that ejects from nozzle 8.Here, will be to describing according to the ink ejection amount bearing calibration that wherein obtains the improvement embodiment of correction coefficient at the respective environment condition.

In order to obtain correction coefficient at the respective environment condition, in the production of head main body 13, when changing environmental condition, repeat to measure the step (first step) of the China ink amount that from the nozzle of each block, ejects and obtain at each block and at the step (second step) of the correction coefficient of each gray level according to measurement result.For example, at first temperature is set at 10 ℃, carries out the first step and second step then to obtain the correction coefficient under 10 ℃.Then, be 20 ℃ with temperature change, carry out the first step and second step then to obtain the correction coefficient under 20 ℃.Subsequently, changing temperature with 10 ℃ increment, repeat first and second steps up to for example in 50 ℃.Therefore, obtain the corresponding correction coefficient in 10 ℃ to 50 ℃ scopes, and they are stored in the correction coefficient table that is used for each temperature of mapping table storage area 149.

On the other hand, have environmental sensor for example temperature sensor or humidity sensor (not shown) according to this improved printer 1.Before printer 1 carried out gray level printing, waveform selected part 150 to select a correction coefficient table that is used for relevant temperature that is stored in the mapping table storage area 149 according to the output of temperature sensor.For example, if be designated as 20 ℃ from the output of temperature sensor, then waveform select part 150 select to be stored in the mapping table storage area 149 at 20 ℃ correction coefficient table.Then, waveform select print command that part 150 responses provide from communications portion 141 and with reference to selected correction coefficient table to determine the waveform that is used for each block.

According to this improvement, mapping table storage area 149 stores the correction coefficient table at respective environment condition (for example temperature), and printer 1 comprises environmental sensor (for example, temperature sensor).Therefore, even under the environmental condition situation jumpy the user moves on to printer 1 another place and printer 1 from a place around, this printer 1 also can be dealt with this environmental change, and makes that the difference aspect the China ink amount that goes out from nozzle ejection is less between block.

Next, with reference to Figure 11 the method that is used to proofread and correct ink ejection amount according to second embodiment of the invention is described.Figure 11 is the view of method that is used to proofread and correct ink ejection amount that is used for illustrating according to second embodiment.By the way, used structure according to the printer of the method for the correction ink ejection amount of second embodiment on it with identical according to the structure of first embodiment.For the repetitive description thereof will be omitted, identical label is represented identical parts.

This method that is used for proofreading and correct ink ejection amount is a kind of method that is used for determining as the corresponding correction coefficient of the content of the correction coefficient table that is stored in correction coefficient storage area 148.At first, in each block of block A to I, measure the China ink amount (first step) that ejects from nozzle 8.Be used to measure aspect the structure and method of ink ejection amount, this second embodiment is identical with first embodiment, thereby will omit its explanation.

As shown in figure 11, the ink ejection amount in each block of measuring when the length direction of head main body 13 changes to X1, X2 and X3 successively with the position of dummy line at block A to I is promptly measured three times.

Then, determine correction coefficient (second step) according to the ink ejection amount of measuring by said method.At first, according to three ink ejection amounts that the dummy line X1 to X3 in each block that is used in block A to I measures, determine the reference line which bar dummy line conduct of adopting among the dummy line X1 to X3 is used for the calculation correction coefficient.Specifically, with nozzle 8 quantity of each ink ejection amount, calculate the ink ejection amount of each nozzle 8 thus divided by a corresponding dummy line that depends on dummy line X1 to X3.Then, arrange the ink ejection amount of each nozzle 8 that is calculated according to the order of dummy line X1 to X3.By the absolute value of the variable quantity of the ink ejection amount of each nozzle 8 between two adjacent virtual lines relatively, from these dummy line X1 to X3, determine reference line.By the way, when variable quantity was zero, X1 was defined as reference line with dummy line.Calculate: the absolute value of variable quantity between ink ejection amount that calculates at dummy line X1 and the ink ejection amount that calculates at dummy line X2; And the absolute value of variable quantity between ink ejection amount that calculates at dummy line X2 and the ink ejection amount that calculates at dummy line X3.If the value of back greater than the value of front, then is defined as reference line with dummy line X2.If the value of front greater than the value of back, then is defined as reference line with dummy line X1.For the method that is used for determining according to ink ejection amount correction coefficient, second embodiment is identical with first embodiment, thus the explanation that will omit this method.

According to above-mentioned second embodiment, because can determine the most effective block, so can accurately proofread and correct ink ejection amount.Therefore, the density unevenness that can be suppressed at reliably in the print result is spared property.

Then describe with reference to Figure 12 to 14 pair of line head ink-jet printer according to third embodiment of the invention.By the way, for the repetitive description thereof will be omitted, identical label is represented identical parts.

With reference to Figure 12 the controller 100 according to the 3rd embodiment is elaborated below.Figure 12 is the functional-block diagram according to the controller 100 of the 3rd embodiment.This controller 100 comprises: CPU (CPU), as processor; ROM (read-only storage) is used for storing by the program of CPU execution with in the used data of these programs; RAM (random access memory) is used for temporarily storing data when these programs of execution; And a driver IC, be used for drive actuator unit 21.These building block collaborative works make funtion part described below to work.

Controller 100 is operated according to the instruction that provides from personal computer (PC) 200.As shown in figure 12, controller 100 comprises that on function communications portion 341, operation control section 342 and print control section divide 343.By the way, each funtion part is by for example ASIC (special IC) realization of hardware.All these funtion parts can be realized by software by software realization or partial function part.

Print control section divides 343 according to the instruction execution printing relevant with printing that provides from PC200.This print control section divides 343 to have correction coefficient storage area 344, waveform determining section 345, a waveform storage area 346, waveform selection part 347 and pulse generation part 348.

Correction coefficient storage area 344 stores the correction coefficient table of setting at each block, and each block includes at least one nozzle 8 in the ink-jet zone of head main body 13.The ink ejection amount of each nozzle 8 of each correction coefficient basis in this block is with this block classification.Ratio according to the desirable ink ejection amount of the ink ejection amount of each nozzle 8 in each block and a nozzle 8 is determined each correction coefficient.The structure of producing can so that: determine correction coefficient according in the production process of head main body 13, measuring a kind of like this mode of ink ejection amount at each block.Optionally, the structure of producing can so that: according to suitably measuring a kind of like this mode of ink ejection amount at each block and determine correction coefficient by being located at the sensor that is used to measure ink ejection amount in the printer 1.The same as hereinafter described, by proofreading and correct the China ink amount that ejects from nozzle 8 at each block, minimize in the difference aspect the ink ejection amount of each nozzle 8 thereby can make between these blocks according to correction coefficient.

These blocks can limit as shown in fig. 8.Fig. 8 is a plane, demonstrates the ink-jet zone in head main body 13.Zone corresponding with each actuating unit 21 on the position is illustrated by the broken lines.This area limiting pressure chamber's group 9 and its shape be similar to trapezoidal.In the respective regions that defines pressure chamber's group 9, be formed with big flow nozzle 8 (referring to Fig. 2 and 3).As shown in Figure 8, the ink-jet zone is divided into nine block A to I by eight dummy line that the throughput direction along print paper P extends.Every the dummy line process will define the trapezoidal hypotenuse of pressure chamber's group 9 and the summit that this trapezoidal minor face links together.That is to say that these dummy line are set for and made these dummy line pass through along the structural change point of the head main body 13 of the direction extension vertical with the throughput direction of print paper P.Table 4 demonstrates and embodiment in the corresponding correction coefficient of the block A to I shown in Fig. 8.

Table 4

Block	Correction coefficient
Block	Correction coefficient	A	0
B	0	A	0
B	0	C	0
D	1	C	0
D	1	E	1
F	1	E	1
F	1	G	0
H	0	G	0
H	0	I	0

As shown in table 4, will be by two correction coefficient " 0 " and " 1 " in the block classification in the ink-jet zone of head main body 13.Correction coefficient " 0 " represents that the ink ejection amount of each nozzle 8 is standards.Correction coefficient " 1 " represents that the ink ejection amount of each nozzle 8 is less than standard.By the way, can set correction coefficient by an arbitrary number grade.

Waveform determining section 345 determines that according to the correction coefficient table that is stored in the correction coefficient storage area 344 the impulse waveform pattern (waveform) of each block makes up, make: compare with the difference adopt situation about making up with corresponding gray level corresponding and identical waveform patterns (waveform) for all blocks under, the difference aspect the ink ejection amount of each nozzle 8 is less between these blocks when gray level printing.The waveform patterns kind number n that determines (selection) is greater than the number of grayscale levels m in gray level printing.For example, when number of grayscale levels m was 3 (not comprising not ink-jet situation), the kind number n of waveform patterns was equal to or greater than 4.Determine these waveform patterns, so that from these nozzles, eject the China ink of different amounts.

Figure 13 demonstrate number of grayscale levels m be 3 and waveform patterns kind number n be the embodiment of 4 o'clock waveform patterns.By the way, vertical axis represents to be applied to the voltage on each single electrode 35, and horizontal axis is represented the time.As mentioned above, in the 3rd embodiment, will offer single electrode 35 based on the pulse of high potential to eject ink droplet.As shown in figure 13, each waveform patterns of waveform patterns i to iv comprises at least one injection pulse and a cancellation pulse.Injection pulse is used for ejecting ink droplet from nozzle 8, thereby a pulse can be ejected an ink droplet.Waveform patterns i includes an injection pulse.Waveform patterns ii includes two injection pulses.Waveform patterns iii includes three injection pulses.Waveform patterns iv includes four injection pulses.That is to say that ink ejection amount increases according to the order of waveform patterns i to iv.The cancellation pulse is used for removing the residual pressure that is retained in the independent black flow channel 32 after ink-jet.The cancellation pulse with anti-phase cycle in the cycle of residual pressure in independent black flow channel 32, produce the pressure that makes new advances.Therefore, use the pressure that produces by the cancellation pulse to cancel this residual pressure.As shown in the table 5, add 3 codes (001 to 100) that are used to specify these waveform patterns to these waveform patterns i to iv respectively.

Table 5

Waveform patterns	Code
Waveform patterns	Code	i	001
ii	010	i	001
ii	010	iii	011
iv	100	iii	011

The combination of the waveform patterns that waveform storage area 346 is determined by waveform determining section 345 at each block stores.Table 6 demonstrates by the combination of waveform determining section 345 according to the definite waveform patterns of the data in table 4 and 5.By the way, being used in three kinds of gradation datas in the gray level printing is dropped on the little ink droplet of the size of the ink droplet on the print paper P, middle ink droplet and big ink droplet and represents by expression.

Table 6

Block	Little ink droplet	Middle ink droplet	Big ink droplet
Block	Little ink droplet	Middle ink droplet	Big ink droplet	A	001	010	011
B	001	010	011	A	001	010	011
B	001	010	011	C	001	010	011
D	010	011	100	C	001	010	011
D	010	011	100	E	010	011	100
F	010	011	100	E	010	011	100
F	010	011	100	G	001	010	011
H	001	010	011	G	001	010	011
H	001	010	011	I	001	010	011

As shown in table 6, the ink ejection amount of each nozzle 8 is among the block A to C and block G to I of standard (correction coefficient " 0 ": referring to table 4) therein, successively waveform patterns i to iii is distributed to little ink droplet, middle ink droplet and big ink droplet.The ink ejection amount of each nozzle 8 is among the block D to F of little (correction coefficient " 1 ": referring to table 4) therein, successively waveform patterns ii to iv is distributed to little ink droplet, middle ink droplet and big ink droplet so that increase the ink ejection amount of each nozzle 8.Therefore, in block A to I, and use the situation of the combination of identical waveform patterns i to iii that is used for corresponding gray level or ii to iv to compare, can be reduced in the difference of the ink ejection amount aspect of each nozzle 8 for all block A to I.

Waveform selects part 347 to select the waveform patterns (waveform) of each block that is used for block A to I according to the waveform patterns combination of each block that is used for block A to I of the gradation data that drops on the ink dot on the print paper P (little ink droplet, middle ink droplet and big ink droplet) from be stored in waveform storage area 346.Then, waveform is selected part 347 to make pulse produce part 348 and is produced the pulse with selected waveform patterns, and the pulse that is produced is offered a corresponding single electrode 35 of actuator 21.Therefore, according to waveform patterns drive actuator unit 21 from respective nozzle 8, ejecting ink droplet, thereby on print paper P, form ink dot with desired gray scale.

Pulse produces part 348 and produces the pulse that has by any waveform patterns among the waveform selection part 347 selected waveform patterns i to iv.Select part 347 pulse that is produced to be offered a corresponding single electrode 35 of actuator 21 by waveform.

According to above-mentioned the 3rd embodiment, change because be used for the ink ejection amount that the combination of waveform patterns i to iv of each block of block A to I proofreaies and correct nozzle 8 at each block of block A to I by change, so can be easy to proofread and correct the variation aspect the ink ejection amount of each nozzle 8 between these blocks A to I when gray level printing.Therefore, can print the high quality image that does not have the even property of density unevenness, can make simultaneously and print the production capacity maintenance efficiently.

And, if suitably change the correction coefficient that is stored in the correction coefficient storage area 344, then can be suppressed at the variation aspect the ink ejection amount of each nozzle 8 between these blocks A to I reliably according to environmental change.

And, because these blocks are divided by the dummy line of extending along the throughput direction of paper P, change image quality is applied big adverse effect so can be limited in ink ejection amount with respect to the length direction of head main body 13 effectively.

In addition, every dummy line is by a summit, and this summit is the structural change point in head main body 13, and this summit will define the hypotenuse of trapezoid area of actuating unit 21 and the minor face of trapezoid area links together.Therefore, because this structure of head main body 13 can be made correction more fully.

Then the improvement embodiment of the 3rd embodiment is described with reference to Figure 14.In the 3rd embodiment, the print control section of controller 100 divides 343 to have correction coefficient storage area 344 and waveform determining section 345, thereby waveform determining section 345 is determined the content that will be stored in the waveform storage area 346 according to the content that is stored in the correction coefficient storage area 344.But, the invention is not restricted to this structure of the 3rd embodiment.As shown in figure 14, controller 100 can be configured such that: predetermined content is stored in the waveform storage area 346, and does not comprise correction coefficient storage area 344 and waveform determining section 345.

Though the preferred embodiments of the invention are illustrated, the present invention is not limited to above-mentioned embodiment.Can be below not breaking away from make various design variation under the situation of scope of appending claims and the claim introduced.For example, though the situation of extending along the direction vertical with the throughput direction of print paper P at dummy line wherein is illustrated top embodiment, dummy line can be set (qualification) one-tenth and extend along any direction.Though above-mentioned embodiment is illustrated by the situation that single straight line forms at every dummy line wherein, every dummy line can be formed (that is, every dummy line can be a broken line) by many straight lines or include curve.

Though at the situation by the structural change point in head main body 13 of dummy line wherein above-mentioned embodiment is illustrated, the present invention is not limited to this structure.These dummy line can be by the structural change point in head main body 13.In this case, preferably, arrange these dummy line along the direction vertical with the throughput direction of print paper P according to the distance between these dummy line.

In the above-described embodiment, each block of block A to I comprises a plurality of nozzles 8.But, the block that includes only a nozzle 8 can be set.

In first and second embodiments, instrument 112 is measured ink ejection amount with weighing.Instead, can measure the volume that sprays ink droplet.

In these embodiments, number of grayscale levels m is 3, and the kind number n of waveform patterns is 4.But the present invention is not limited to this ad hoc structure.The kind number n of number of grayscale levels m and waveform patterns can select arbitrarily, if the kind number n of waveform patterns be equal to or greater than 3 and number of grayscale levels m be equal to or greater than 2 and less than the kind number n of waveform patterns.For example, number of grayscale levels m can be 4, and the kind number n of waveform patterns can be 6.Optionally, number of grayscale levels m can be 3, and the kind number n of waveform patterns can be 5.In this case, the number of levels based on correction coefficient that is used for the ink ejection amount classification can be set at 3.

Claims

1. line head ink-jet printer comprises:

Ink gun, described ink gun is divided into N block by the N-1 bar dummy line that the throughput direction along print media extends, and wherein N represents to be equal to or greater than 2 natural number, and this ink gun comprises:

Flow channel unit, this flow channel unit be formed with a plurality of respectively with the nozzle pressure chambers communicating; And

A plurality of single electrodes, described a plurality of single electrodes are arranged to corresponding with described a plurality of pressure chamber respectively;

Controller, this controller produce and are used for ejecting the n kind waveform that different China inks are measured respectively from described nozzle, and wherein n is equal to or greater than 3 natural number; And

Memory cell, this memory cell is selected from the combination of the m kind waveform of described n kind waveform at each block stores that comprises at least one nozzle of a described N block, and wherein m is natural number and 2≤m≤n-1, wherein:

When the described m kind waveform that is selected from described n kind waveform in use when described printer carries out gray level printing, use in the situation of combination of the described m kind waveform of being stored at each block at a described N block, between described each block in the difference aspect the ink ejection amount of each nozzle less than the difference in the situation of a like combinations using described m kind waveform at all blocks at a described N block;

Select the waveform of each block that is used for a described N block in the combination of described controller according to the described m kind waveform of gradation data from be stored in described memory cell of input, thereby selected waveform is exported to the single electrode of each block of a described N block.

2. printer as claimed in claim 1, a wherein said N block is arranged along the length direction of described flow channel unit.

3. as the described printer of each claim in the claim 1 to 2, the structural change point of wherein said dummy line by in described ink gun, extending along the direction vertical with described throughput direction.

4. printer as claimed in claim 3, wherein:

Described ink gun also comprises:

A plurality of actuating units with trapezoidal shape, each described actuating unit comprises:

Piezoelectric patches, this piezoelectric patches extends in described a plurality of pressure chamber; With

Common electrode, this common electrode and described a plurality of single electrode are clipped in described piezoelectric patches between described common electrode and the described a plurality of single electrode;

Each described single electrode is arranged on the described piezoelectric patches and is corresponding with each described pressure chamber on the position;

Described actuating unit is arranged on the described flow channel unit, makes the hypotenuse of the adjacent actuators unit in described a plurality of actuating unit overlapped when described throughput direction is observed; And

At each described structural change point place that every described dummy line is passed through, the hypotenuse of each described actuating unit and the minor face of each described actuating unit intersect.

5. as the described printer of each claim in the claim 1 to 2, wherein:

Described ink gun also comprises:

Described actuating unit is arranged on the described flow channel unit; And

At least one block in the described N block comprises the whole borderline region between two adjacent actuators unit in described a plurality of actuating units.

6. line head ink-jet printer comprises:

The form stores unit, this form stores unit storage form, in the ink ejection amount classification of each nozzle of N block basis described in this form in each block of a described N block, each block in the described N block all comprises at least one nozzle; And

Controller, this controller produce and are used for ejecting the n kind waveform that different China inks are measured respectively from nozzle, and wherein n is equal to or greater than 3 natural number, wherein:

When the m kind waveform that is selected from described n kind waveform in use when described printer carries out gray level printing, wherein m is natural number and 2≤m≤n-1, described controller is determined the combination of described m kind waveform at each block of a described N block, make and use in the situation of combination of determined described m kind waveform at each block at a described N block, between described each block in the difference aspect the ink ejection amount of each nozzle less than the difference in the situation of a like combinations using described m kind waveform at all blocks at a described N block;

Described controller is with the combination storage afferent echo shape memory cell of the described m kind waveform of determined each block that is used for a described N block; And

Select the waveform of each block that is used for a described N block in the combination of described controller according to the described m kind waveform of gradation data from be stored in described waveform memory cell of input, thereby selected waveform is exported to the single electrode of each block of a described N block.

7. printer as claimed in claim 6, a wherein said N block is arranged along the length direction of described flow channel unit.

8. as the described printer of each claim in the claim 6 to 7, the structural change point of wherein said dummy line by in described ink gun, extending along the direction vertical with described throughput direction.

9. printer as claimed in claim 8, wherein:

Described ink gun also comprises:

Piezoelectric patches, this piezoelectric patches in described a plurality of pressure chamber, extend and

10. as the described printer of each claim in the claim 6 to 7, wherein:

Described ink gun also comprises:

Described actuating unit is arranged on the described flow channel unit; And