CN1700987A

CN1700987A - Recording head, carriage and image forming apparatus

Info

Publication number: CN1700987A
Application number: CN 200480001193
Authority: CN
Inventors: 尾方贤一; 吉田崇裕; 江口裕俊
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 2003-03-24
Filing date: 2004-03-23
Publication date: 2005-11-23
Anticipated expiration: 2024-03-23
Also published as: CN100532102C; JP2004284196A; JP4190322B2

Abstract

A recording head is provided with a plurality of nozzles for ejecting a fluid, a plurality of pressure-applied chambers arranged in a predetermined direction and each communicating with a corresponding one of the nozzles, and a common chamber having a plurality of wall surfaces and configured to supply the fluid to the pressure-applied chambers. At least one of the wall surfaces of the common chamber, along the predetermined direction, has a pressure absorbing surface with a rigidity lower than those of other wall surfaces and configured to absorb a pressure change, and the pressure absorbing surface is formed by a pressure absorbing member having a non-uniform thickness.

Description

Record head, carrier and imaging device

Technical field

Present invention relates in general to record head, carrier and imaging device, and more specifically, relate to the record head that is used to spray such as the such fluid of ink, have the carrier of at least one record head and have the imaging device of at least one carrier.

Ink jet recording device can be used as the imaging device that is used for printer, facsimile equipment, copier, plotter etc.Ink jet recording device is equipped with ink jet print head, and this ink jet print head comprises black circulation road and pressure conversion device, and this pressure conversion device is used for coming ink is exerted pressure by the pressure that changes in the black circulation road.The China ink circulation road is also referred to as ink-jet chamber, pressure chamber, pressurized China ink chamber, black chamber or the like usually.

Background technology

A kind of known ink jet print head is arranged, and this record head uses electric mechanical conversion element (such as piezoelectric element) as the pressure conversion device that is used for the ink in the black chamber is exerted pressure changeably.Utilize pressure conversion device, deformation takes place in the elastically deformable oscillating plate that constitutes ink cavity wall under the effect of drive unit, so that by changing volume and/or the pressure ejection ink droplet in the black chamber.The ink jet print head that so-called piezo-electric type ink jet print head comes to this.For example, Japanese Laid-Open Patent Application has proposed a kind of like this piezo-electric type ink jet print head for 8-108534 number.

Provide the explanation of piezo-electric type ink jet print head below with reference to Fig. 1 and 2.Fig. 1 is the sectional view of expression along the piezo-electric type ink jet print head of vertical (that is, along the direction vertical with the direction of the nozzle arrangement) intercepting in pressurized China ink chamber.Fig. 2 is expression along the sectional view perpendicular to the piezo-electric type ink jet print head of the direction longitudinally in the pressurized China ink chamber direction of nozzle arrangement (that is, along) intercepting.

Ink jet print head shown in Fig. 1 and 2 comprises black cavity substrate 211 and the nozzle plate 218 that interconnects.Pressurized China ink chamber 214 is communicated with the nozzle 213 that sprays ink droplet.Common ink chamber 219 is supplied inks by communication means 220 to pressurized China ink chamber 214.Piezoelectric element 217 is arranged on the base substrate 212, is positioned at the outside of the oscillating plate 216 of a part that constitutes pressurized China ink chamber 214 walls.

Deformation takes place and carries out elastic deformation along with piezoelectric element 217 in oscillating plate 216.For the displacement with piezoelectric element converts the volume-variation in pressurized China ink chamber 214 effectively to, the rigidity of oscillating plate 216 is less than other rigidity that constitutes the surface in pressurized China ink chamber 214 usually.In other words, the flexibility of oscillating plate 216 is greater than other the surperficial flexibility that constitutes pressurized China ink chamber 214 usually.In addition, common ink chamber 219 is connected with the print cartridge (not shown), and is provided with support member 221 between black cavity substrate 211 and base substrate 212.

Make piezoelectric element 217 that deformation take place by applying voltage to piezoelectric element 217,, thereby increase or reduce the volume in pressurized China ink chamber 214 so that oscillating plate 216 is subjected to displacement from the drive circuit (not shown).When the volume in pressurized China ink chamber 214 increased, the internal pressure in pressurized China ink chamber 214 reduced, thereby ink is fed to the pressurized China ink chamber 214 through communication means 220 from common ink chamber 219.

After this, drive the internal pressure that piezoelectric element 217 consequently increases pressurized China ink chamber 214.In other words, when driving piezoelectric element 217 so that reduce the volume in pressurized China ink chamber 214, the internal pressure of pressurized sap cavity 214 increases, thereby ink sprays from nozzle 213 with the form of ink droplet 222.Ink droplet 222 adheres on recording medium (such as the paper) (not shown), with document image on this recording medium etc.

Ink jet print head can use the pressure conversion device of other element conduct the impelling ink ejection except piezoelectric element, and heating power urges device, marmem urges device and static urges device such as using.By using the element that current conversion is become heat, such as heating resistor, heating power urges the phase transformation that device has utilized the film boiling by ink to cause.Marmem urges the device serviceability temperature and changes the metal phase change that causes.Static urges device and uses electrostatic force.

When ink droplet sprays as mentioned above, need to increase the pressure in pressurized China ink chamber from ink jet print head.In addition, the pressure that is produced has not only caused ink outwards to spray, and can impose on the common ink chamber.But, when the pressure that imposes on the common ink chamber was applied on the pressurized China ink chamber once more, the pressure in pressurized China ink chamber can change.

Particularly under the situation of the ink jet print head with big flow nozzle, the pressure when multichannel drives changes meeting very greatly, and can cause the resonance (phase mutual interference) in black chamber.If the resonant frequency of oscillating plate is consistent with the driving frequency of record head, the ink-jet phenomenon can take place, thereby reduced the image quality of institute's document image.

In order to prevent the problem relevant with resonant frequency, the pressure buffer that needs to increase the common ink chamber is renderd a service.In general, this is that volume by the common ink chamber is set to less relatively value and realizes.On the other hand, Japanese Laid-Open Patent Application has proposed another kind of method 6-191030 number, and this method is provided with a plurality of cushion chambers between black chamber and common ink chamber, changes with the pressure that absorbs in the black chamber.

In addition, though be to be used for different purposes, Japanese Laid-Open Patent Application has proposed for 2000-158668 number a kind ofly in the ink-feed channel of ink jet print head a plurality of cushion chambers to be set at print cartridge, so that absorb the method for the variation of ink supply pressure.In other words, be provided with cushion chamber and reduce the variation of the pressure when the ink supply of the common ink chamber of ink jet print head from the outside.

But, because according to Japanese Laid-Open Patent Application 6-191030 number, cushion chamber is that each the independently black chamber for ink jet print head is provided with, and therefore is difficult to fully reduce the rigidity of cushion chamber.And it is complicated that the structure of ink gun becomes, thereby need complicated production technology to produce ink jet print head.Recently, development trend is that the quantity that increases the ink jet print head nozzle is catered to the demand to altitude record, but the structure that proposes in Japanese Laid-Open Patent Application 6-191030 number is not suitable for being applied to this development trend.

On the other hand, what the ink jet print head that proposes among the Japanese Laid-Open Patent Application 2000-158668 reduced is beating in the ink supply, and the common ink cavity pressure that does not absorb when driving ink jet print head changes.In addition, it is complicated that the structure of ink jet print head becomes, thereby need complicated production technology to produce ink jet print head.

Summary of the invention

General purpose of the present invention provides a kind of record head, carrier and imaging device, and wherein the problems referred to above have obtained solution.

The more concrete purpose of the present invention provides a kind of record head, a kind of carrier and a kind of imaging device, changes by cushion the common cavity ground pressure effectively in the resonance that reduces common cavity, can realize at a high speed and high quality record.

Another object of the present invention provides a kind of record head, comprising: a plurality of nozzles that are used to spray fluid; A plurality of pressurizeds chamber, they are arranged and communicate with one of respective nozzles separately along predetermined direction; And common cavity, have a plurality of wall surfaces, and constitute and be used for to pressurized chamber accommodating fluid, has pressure receiving surface along at least one of predetermined direction in the wall surface of common cavity, this pressure receiving surface has the rigidity that is lower than other wall surface, and constitute and be used for absorption pressure and change, described pressure receiving surface is to be made of the pressure absorption component with non-homogeneous thickness.According to record head of the present invention, the resonant frequency that can in the rigidity of sorbent surface that keep-ups pressure, suppress pressure receiving surface, so that the driving frequency and the resonant frequency of driving head dissimilate, and can obtain stable fluid spray characteristic, even with the high-speed driving record head time, also be like this.For this reason, can be with the image of high-speed record high picture quality.

Another object of the present invention provides a kind of record head, comprising: a plurality of nozzles that are used to spray fluid; A plurality of pressurizeds chamber, they are arranged and communicate with one of respective nozzles separately along predetermined direction; Common cavity has a plurality of wall surfaces, and constitutes and be used for to pressurized chamber accommodating fluid; With a plurality of pressure conversion devices, be used to change the pressure in this pressurized chamber, has pressure receiving surface along at least one of predetermined direction in the wall surface of common cavity, this pressure receiving surface has the rigidity that is lower than other wall surface, and constitute and be used for absorption pressure and change, described pressure receiving surface is to be made of the pressure absorption component with the different a plurality of parts of rigidity.According to record head of the present invention, the resonant frequency that can in the rigidity of sorbent surface that keep-ups pressure, suppress pressure receiving surface, so that the driving frequency and the resonant frequency of driving head dissimilate, and can obtain stable fluid spray characteristic, even with the high-speed driving record head time, also be like this.For this reason, can be with the image of high-speed record high picture quality.

Another object of the present invention provides a kind of carrier, comprising: one of above-mentioned record head; And fluid box, constitute and be used for to the record head accommodating fluid.According to carrier of the present invention, can be with the image of high-speed record high picture quality.

Another purpose more of the present invention provides a kind of imaging device, comprising: one of above-mentioned record head; Fluid box constitutes and is used for to the record head accommodating fluid; And carrier, holding record head and fluid box, constitute and be used for moving on perpendicular to the main scanning direction of predetermined direction.According to imaging device of the present invention, can be with the image of high-speed record high picture quality.

A further object of the present invention provides a kind of record head, comprising: a plurality of nozzles that are used to spray fluid; A plurality of pressurizeds chamber, they are arranged and communicate with one of respective nozzles separately along predetermined direction; Common cavity has a plurality of wall surfaces, and constitutes and be used for to pressurized chamber accommodating fluid; With a plurality of pressure conversion devices, be used to change the pressure in this pressurized chamber, has padded surface along at least one of predetermined direction in the wall surface of common cavity, this padded surface has the rigidity that is lower than other wall surface, and constitute and be used for by absorption of vibrations pressure, described padded surface is made of the pressure absorption component, this pressure absorption component part has the zone that does not form padded surface, so that padded surface has extended less than the length of common ink chamber along the total length of predetermined direction along predetermined direction.According to record head of the present invention, can irrespectively regulate the rigidity of pressure absorption component with the shape of common cavity, and controlled pressure absorption component resonant frequency.Thereby, can so that the driving frequency of the resonant frequency of pressure absorption component and record head separate, thereby make stabilized fluid spray characteristic and realize that high picture quality becomes possibility, even when with high driving frequency activation record head, also be like this.

Another object of the present invention provides a kind of carrier, the record head of just having introduced above comprising; And fluid box, constitute and be used for to the record head accommodating fluid.According to carrier of the present invention, can at full speed write down the image of high picture quality.

Another purpose more of the present invention provides a kind of imaging device, comprising: the top record head of just having introduced; Fluid box constitutes and is used for to the record head accommodating fluid; And carrier, holding record head and fluid box, constitute and be used for moving on perpendicular to the main scanning direction of predetermined direction.According to imaging device of the present invention, can at full speed write down the image of high picture quality.

A further object of the present invention provides a kind of record head, comprising: a plurality of nozzles that are used to spray fluid; A plurality of pressurizeds chamber, they are arranged and communicate with one of respective nozzles separately along predetermined direction; And common cavity, having a plurality of wall surfaces, and constitute and be used for to pressurized chamber accommodating fluid, at least one wall surface of common cavity has the free vibration surface, and this free vibration surface has than thickness portion and thin part.According to record head of the present invention, the pressure that can suppress and cushion common cavity effectively changes, and improves the size and the cost of characteristics of inkjet and reduction record head.

When reading in conjunction with figure, by following detailed description, other purpose of the present invention and additional features will become apparent.

Description of drawings

Fig. 1 is the sectional view of expression along the piezo-electric type ink jet print head of the direction intercepting vertical with the direction of nozzle arrangement;

Fig. 2 is the sectional view of expression along the piezo-electric type ink jet print head of the direction intercepting of nozzle arrangement;

Fig. 3 is the exploded perspective view of expression according to first embodiment of record head of the present invention;

Fig. 4 is the sectional view of expression along first embodiment of the record head of the direction intercepting vertical with the nozzle arrangement direction;

Fig. 5 is the reciprocal cross-section figure of expression along first embodiment of the record head of the direction intercepting of nozzle arrangement;

The sectional view that Fig. 6 is expression along amplifying in proportion of the part in the common ink chamber of nozzle arrangement direction intercepting;

Fig. 7 is used to explain the plane of pressure absorption component;

Fig. 8 is used to explain the plane of another kind of pressure absorption component;

The sectional view that Fig. 9 is expression along amplifying in proportion of the common ink chamber of first comparative example of nozzle arrangement direction intercepting;

Figure 10 is used to explain the schematic diagram of when the driving frequency with 4kHz drives first comparative example vibration mode of the wall surface in common ink chamber;

Figure 11 is used to explain the schematic diagram of driving frequency with the 16.8kHz vibration mode of the wall surface in common ink chamber when driving second comparative example;

Figure 12 is used to explain the curve map of the frequency characteristic that the pressure in common ink chamber of first comparative example changes;

Figure 13 is used to explain the curve map of the frequency characteristic that the pressure in common ink chamber of first kind of embodiment of record head changes;

Figure 14 is used to explain the curve map of pressure resonance characteristics in the Young's modulus of pressure absorption component of first embodiment of record head and common ink chamber;

Figure 15 is the plane of expression according to the pressure absorption component of the first modification embodiment of first embodiment of record head of the present invention;

Figure 16 is used to explain the curve map of the frequency characteristic that first pressure of revising the common ink chamber of embodiment of first embodiment of record head changes;

Figure 17 is expression along revising the sectional view of the part of embodiment perpendicular to the intercepting of the direction of nozzle arrangement direction according to second of first embodiment of record head of the present invention;

Figure 18 is the stereogram of expression according to first embodiment of imaging device of the present invention;

Figure 19 is used to explain the side view of a part of imaging device shown in Figure 18;

Figure 20 is expression along the sectional view according to the part of second embodiment of record head of the present invention perpendicular to the intercepting of the direction of nozzle arrangement direction;

Figure 21 is the sectional view of expression along the part of second embodiment of the record head of nozzle arrangement direction intercepting;

Figure 22 is the exploded perspective view of second embodiment of expression record head;

The sectional view that Figure 23 is expression along amplifying in proportion of the common ink chamber of second embodiment of the record head of the direction of nozzle arrangement intercepting;

Figure 24 is the reciprocal cross-section figure of second embodiment of the record head of the straight line A-A intercepting of expression in Figure 23;

Figure 25 be the expression comprise common ink chamber and ink supply opening record head second embodiment only a part sectional view, the pressure absorption component is used to explain;

Figure 26 be the expression comprise common ink chamber and ink supply opening record head first comparative example only a part schematic diagram, the pressure absorption component is used to explain;

Figure 27 is used to explain the curve map of the frequency characteristic that the pressure in common ink chamber of second embodiment of record head changes;

Figure 28 is expression along the sectional view of revising embodiment perpendicular to first of second embodiment of the record head of the direction of nozzle arrangement direction intercepting;

Figure 29 is the second only sectional view of a part that comprises common ink chamber and ink supply opening of revising embodiment of second embodiment of expression record head, and the pressure absorption component is used to explain;

Figure 30 is the stereogram of expression according to the 3rd embodiment of record head of the present invention;

Figure 31 is the sectional view of the 3rd embodiment of the record head of the straight line A-A intercepting of expression in Figure 30;

Figure 32 is the sectional view of the 3rd embodiment of the record head of the straight line B-B intercepting of expression in Figure 30;

Figure 33 is the exploded perspective view of the 3rd embodiment of expression record head;

Figure 34 is the stereogram that oscillating plate is observed from its basal surface shown in expression Figure 33;

Figure 35 is the exploded perspective view of expression according to the first modification embodiment of the 3rd embodiment of record head of the present invention;

Figure 36 is the stereogram of the oscillating plate shown in Figure 35 of watching from the basal surface of oscillating plate of expression;

Figure 37 is the exploded perspective view of expression according to the second modification embodiment of the 3rd embodiment of record head of the present invention;

Figure 38 is the stereogram of the oscillating plate shown in Figure 37 of watching from the basal surface of oscillating plate of expression;

Figure 39 is the exploded perspective view of expression according to the 3rd modification embodiment of the 3rd embodiment of record head of the present invention;

Figure 40 is the stereogram of the oscillating plate shown in Figure 39 of watching from the basal surface of oscillating plate of expression;

Figure 41 is used to explain side view according to the part of the 3rd embodiment of imaging device of the present invention; With

Figure 42 is the plane of the part of the imaging device shown in expression Figure 41.

The specific embodiment

At first, provide explanation with reference to Fig. 3 to 5 according to first embodiment of record head of the present invention.Fig. 3 is the exploded perspective view of this first embodiment of expression record head, and Fig. 4 is the sectional view of expression along this first embodiment of the ink gun of vertical (promptly along the direction vertical with the nozzle arrangement direction) intercepting in pressurized China ink chamber.Fig. 5 is the reciprocal cross-section figure of expression along this first embodiment of the record head of direction (A-A among Fig. 4) intercepting of nozzle arrangement.This first embodiment according to record head has been applied to the present invention in the ink jet print head.

Ink jet print head shown in Fig. 3 to 5 comprises: the flow channel of being made by monocrystalline silicon (Si) constitutes substrate (black cavity substrate) 1, be arranged on oscillating plate 2 on the lower surface that flow channel constitutes substrate 1, be arranged on nozzle plate 3 and framing component 14 (being introduced after a while) on the upper surface that flow channel constitutes substrate 1.Flow channel constitutes substrate 1, oscillating plate 2, nozzle plate 3 and framing component 14 and has constituted pressurized China ink chamber 6 and common ink chamber 8.Each nozzle that sprays ink droplet communicates with a pressurized China ink chamber 6, and this pressurized China ink chamber 6 has constituted flow channel.To pressurized China ink chamber 6 supply inks, communication means 7 has constituted the choked flow part through ink-feed channel (communication means) 7 in common ink chamber 8.

On outer surface one side of oscillating plate 2, that is, on a side opposite,, be provided with stacked piezoelectric element 12, as drive unit at each pressurized China ink chamber 6 with pressurized China ink chamber 6.Piezoelectric element 12 is fixed on the base substrate 13.

On framing component 14, be formed with flow channel and constitute the groove part that substrate 1 constitutes common ink chamber 8.In addition, be formed with ink supply opening (connecting pipe) 9 on framing component 14, this ink supply opening 9 is supplied inks from the outside to common ink chamber 8.This ink supply opening 9 is communicated with ink supply source (not shown) such as print cartridge.

Flexible print circuit (FPC) cable 18 by the welding, AFC is bonding or wire-bonded is connected with piezoelectric element 12, is used for supplies drive signals.FPC cable 18 is equipped with drive circuit (driver IC), is used for applying drive waveforms to each piezoelectric element 12 selectively.

By using the alkaline etching such as potassium hydroxide (KOH) solution, to have＜110〉crystal orientation monocrystalline silicon substrate carries out anisotropic etching, constitute at flow channel to have formed the groove that is used to constitute the through hole in pressurized China ink chamber 6 and is used to constitute ink-feed channel 7 on the substrate 1.

Oscillating plate 2 is made by the metallic plate that forms by electroforming.Be formed on the nozzle plate 3 with corresponding each nozzle 5 of one of pressurized sap cavity 6, have about 10 to about 30 diameter.Oscillating plate 2 constitutes on the substrate at flow channel by adhesive securement.Can be not used in the formation image with the corresponding pressurized China ink of the nozzle 5a shown in Fig. 5 chamber 6, but nozzle 5a usefulness is acted on the false nozzle of bleeding, to discharge bubble, this nozzle 5a is along an end that vertically is positioned at common ink chamber 8 in common ink chamber 8.In addition, the nozzle 5a along the two ends that vertically are positioned at common ink chamber 8 in common ink chamber 8 can be used as so false nozzle.

Nozzle plate 3 can be made by the composition of composition, silicon or these materials of metal, metal and the resin such as polyimide resin film such as stainless steel and nickel (Ni).Nozzle surface (that is, ink is from the surface of its ejection) at nozzle plate 3 is formed with and scolds water layer, is not stained with ink to guarantee nozzle surface.Can adopt known method, scold water layer, on nozzle surface, form and scold water layer such as plating and coating.Slit between sealant 20 applying nozzle plate peripheries and the framing component 14.This sealant 20 is also as bonding agent.

When selectively with about 20V when the driving pulse voltage of about 50V imposes on the piezoelectric element 12 of the ink jet print head with said structure, the piezoelectric element 12 that has applied driving pulse voltage is subjected to displacement on each stacked direction of putting of piezoelectric element 12, thereby oscillating plate 2 on the direction of respective nozzle 5 deformation takes place.As a result, the volume or the capacity in corresponding pressurized China ink chamber 6 change, thereby the ink in this pressurized China ink chamber 6 has been applied pressure, and ink droplet is sprayed from respective nozzle 5, have realized ink mist recording.

Along with the ejection of ink, the ink pressure in the pressurized China ink chamber 6 reduces, thereby under the action of inertia of China ink stream, has produced small negative pressure in pressurized China ink chamber 6.In this state, when stopping when piezoelectric element 12 applies driving pulse voltage, promptly, when cutting off driving pulse voltage, oscillating plate 2 is returned to its initial position and pressurized China ink chamber 6 is returned to its original shape, and the result has produced negative pressure further in pressurized China ink chamber 6.Under this state, ink be able to through the common ink chamber 8 and the ink-feed channel 7 that constitutes the choked flow part be supplied to pressurized China ink chamber 6 from ink supply opening 9.Therefore, the vibration of the ink meniscus on nozzle 5 be suppressed and stable after, apply driving pulse voltage to piezoelectric element 12, spraying ink droplet, thereby realize ink mist recording next time.

In Fig. 3 and 4, shown nozzle 5 is towards last.But when reality was sprayed ink droplet with the realization ink mist recording on the recording medium such as paper, in most of the cases, ink droplet sprayed vertically downward.Therefore, according to present embodiment, in Fig. 5, in the ink mist recording that carries out image, ink droplet can spray vertically downward facing to the recording medium (such as paper) of horizontal feed.

Below, provide the explanation of structure in the common ink chamber 8 of ink jet print head with reference to Fig. 6 to 8.The sectional view that Fig. 6 is expression along amplifying in proportion of the part in the common ink chamber 8 of nozzle 5 orientations interceptings.In addition, Fig. 7 is used to explain the plane of pressure absorption component, and Fig. 8 is used to explain the plane of another kind of pressure absorption component.

According to this embodiment of record head, common ink chamber 8 is to be made of framing component 14 and the rigidity pressure absorption component 21 less than framing component 14, as shown in Figure 6.Pressure absorption component 21 has constituted pressure receiving surface 21a.If the orientation in pressurized China ink chamber 6 is expressed as X, then common ink chamber 8 is made of pressure receiving surface 21a along at least one wall surface of direction X, and this pressure receiving surface 21a has rigidity and the absorption pressure less than other wall surface.

As shown in Figure 6, the pressure absorption component 21 of formation pressure receiving surface 21a has inhomogenous thickness on direction X.In other words, the middle body of pressure absorption component 21 is thicker on average, and two end parts of pressure absorption component 21 are thinner.More specifically, if along direction X pressure receiving surface 21 is divided into 3 roughly the same zones of size, then along direction X, the average thickness of middle body is greater than the average thickness of the end parts of middle body both sides.Like this,, formed than thickness portion 23, and formed thin part 22 in the end parts of the pressure absorption component 21 of the both sides of middle body at the middle body of pressure absorption component 21 along direction X.Certainly, also can pressure receiving surface 21a be divided into more than 3 zones that size is roughly the same, and form than thickness portion 23 at the middle body of pressure absorption component 21 along direction X.This than the rigidity of thickness portion 23 greater than thin part 22, thereby pressure absorption component 21 is to be made of the different a plurality of parts of rigidity.

In this case, pressure absorption component 21 has the laminated construction of being made up of ground floor 21A and second layer 21B.Ground floor 21A constitutes thin part 22, should thin part 22 constitute oscillating plate 2.Second layer 21B is formed on the ground floor 21A, and together constitutes than thickness portion 23 with ground floor 21A.By adopting laminated construction, can make the uneven thickness one of pressure absorption component 21 at an easy rate.And, constitute a part of laminated construction by adopting the layer identical or a plurality of layers with oscillating plate 2, pressure absorption component 21 can be in the processing that forms oscillating plate 2, formed simultaneously, thereby production technology can be simplified.

In this embodiment, formed step portion, can in Fig. 6, see in thin part 22 with than the intersection of thickness portion 23.But, be not that step portion must be set, but the thickness of pressure absorption component 21 can change continuously in thin part 22 with between than thickness portion 23, in other words, thin part 22 and can couple together by the part of continuous tilt than thickness portion 23.Also can have the inhomogenous thickness part different by in thin part 22 with between so continuous changing unit being set, pressure absorption component 21 being made into than thickness portion 23 with rigidity.It is identical being provided with on the pressure absorption component 21 that thin part 22 there is no need with size than the zone of thickness portion 23, and these regional quantity also are not limited to 3 certainly.Thin part 22 and can decide according to the material of pressure absorption component 21, size etc. in the pressure absorption component 21 than the quantity of thickness portion 23 and position, and if necessary, can be optimized.

As shown in Figure 7, the width Uy of the thin part 22 of (that is, the obtaining) obtained along direction, available being arranged to identical than thickness portion 23 along the minor face of pressure absorption component 21 perpendicular to direction X.On the other hand, as shown in Figure 8, the width Uy of the thin part 22 that obtains along the direction perpendicular to direction X can be provided with greater than than thickness portion 23.In Fig. 7 and 8, Ux represents the length of the thin part 22 that obtains along direction X, and Tx represents the total length of the pressure absorption component obtained along direction X.According to present embodiment, thin part 22 and have identical length Ux, but as mentioned above than thickness portion 23, thin part 22 can be different with length than thickness portion 23.

By the thickness of pressure absorption component 21 is made heterogeneity, make the structural vibration in common ink chamber 8 become complicated, thereby make it can suppress the generation of big vibration mode under the low frequency.In addition, the resonant frequency that can prevent driving frequency and common ink chamber 8 is complementary.

And, having the different part of a plurality of rigidity by making pressure absorption component 21, it is complicated that the structural vibration in common ink chamber 8 becomes, thereby make the generation that suppresses big vibration mode under the low frequency become possibility.In addition, the resonant frequency that can prevent driving frequency and common ink chamber 8 is complementary.Certainly, also can be different and/or by being used in the material difference of each several part by the thickness that makes each several part, the each several part of pressure absorption component 21 is made into has different rigidity.

In other words, propagate into other pressurized China ink chamber 6 in order to prevent the pressure vibration that propagates into common ink chamber 8 from the black chamber 6 of pressurized when ink droplet sprays, the pressure buffer that needs to increase common ink chamber 8 is renderd a service.For the pressure buffer that increases common ink chamber 8 is renderd a service, the method that can adopt the Vibrant buffer pressure of the wall surface self by common ink chamber 8 to change perhaps adopts and apply the method that the material (such as rubber) with low elasticity comes the deformation compensator or trimmer pressure of the wall surface by common ink chamber 8 to change on the wall surface in common ink chamber 8.The method that the vibration of the wall surface self by common ink chamber 8 comes compensator or trimmer pressure to change is especially satisfactory, is because produce easily and pressure buffer is renderd a service higher relatively.In this case, producing is because the relatively low and better simply relatively result of production technology of cost easily.

But when the rigidity of the wall surface in common ink chamber 8 is reduced to when being more prone to produce vibration, the pressure that can be produced common ink chamber 8 by the resonance of wall surface self changes.Introduce this phenomenon now with reference to Fig. 9 to 12.The sectional view that Fig. 9 is expression along amplifying in proportion of the common ink chamber of first comparative example of nozzle arrangement direction intercepting.Figure 10 is used to explain the schematic diagram of when the driving frequency with 4kHz drives first comparative example vibration mode of the wall surface in common ink chamber, and Figure 11 is used to explain the schematic diagram of driving frequency with the 16.8kHz vibration mode of the wall surface in common ink chamber when driving second comparative example.In addition, Figure 12 is used to explain the curve map of the frequency characteristic that the pressure in common ink chamber of first comparative example changes.

First comparative example shown in Fig. 9 makes that a part of wall surface in common ink chamber 8 is whole to be made of thin part 22, thereby has reduced the rigidity of pressure absorption component 21.In this case, when the driving frequency with 4 kHz drove this first comparative example, the vibration mode of the wall surface in common ink chamber 8 was the pattern shown in Figure 10.In addition, when driving this second comparative example when the rigidity that does not reduce pressure absorption component 21 for second comparative example and with the driving frequency of 16.8kHz, the vibration mode of the wall surface in common ink chamber 8 is a pattern as shown in figure 11.In Figure 10, the stereogram of two pressure absorption components that the rectangular band of two whites is equivalent to arrange shoulder to shoulder, and in Figure 10 and 11, the black band is represented the deformation of pressure absorption component on x, y and z direction.Figure 10 and 11 expressions vibration mode under these circumstances: the area of the wall surface in common ink chamber 8 is identical for first and second comparative examples, and between first and second comparative examples, the thickness difference of having only the part that constitutes wall surface, thus each wall surface has different rigidity.

As can be seen, the resonant frequency that has second comparative example of the wall surface that does not reduce rigidity with common ink chamber 8 is compared from Figure 10 and 11, and the resonant frequency that common ink chamber 8 has first comparative example of the wall surface that has reduced rigidity has been moved in the low-frequency band.Thus, along with the shortening in the cycle of spraying ink droplet, in other words, along with the driving frequency rising of ink jet print head, the resonant frequency of the wall surface in the common ink chamber 8 of first comparative example may be complementary with driving frequency.Under normal circumstances, the driving frequency of ink jet print head is in the order of magnitude of big approximate number kHz to about tens kHz.Like this, the frequency band of driving frequency is lower than the resonant frequency in common ink chamber 8, but under the situation that the rigidity of the wall surface in common ink chamber 8 reduces, resonant frequency reduces, thereby the resonant frequency that has reduced may be complementary with the driving frequency of ink jet print head.

On the resonance point of the wall surface in common ink chamber 8, the pressure in common ink chamber 8 self takes place sharply to change under the effect of wall surface vibration.Like this, when in the rigidity of the wall surface in common ink chamber 8 is reduced to according to first comparative example, constituting pressure absorption component 21 like that, the frequency characteristic that the pressure in common ink chamber 8 changes has become as shown in Figure 12, and pressure changes the value that shows very greatly under resonant frequency.In Figure 12, the longitudinal axis is represented the pressure (kPa) in the common ink chamber 8 of first comparative example, and transverse axis is represented frequency (kHz).

Therefore, in statu quo being provided with in fact may be owing to being provided with the pressure variation that this pressure absorption component 21 increases common ink chamber 8 with the pressure absorption component 21 of the pressure in buffering common ink chamber 8.In order to prevent that pressure absorption component 21 from increasing the pressure variation in common ink chamber 8, the resonant frequency that the driving frequency of ink jet print head must be set for not with the wall surface in common ink chamber 8 is complementary, thereby in this case, the drive condition of ink jet print head is restricted.

As mentioned above, development trend is the quantity that increases the nozzle 5 of ink jet print head, so that cater to the demand of high-speed record.But, along with the increase of the quantity in the increase of nozzle 5 quantity and the independently pressurized China ink chamber 6 of causing thus, common ink chamber 8 can increase along the length of the direction X that arranges pressurized China ink chamber 6.As a result, pressure absorption component 21 also can increase along the length of direction X.But along with the increase of pressure absorption component 21 length, its rigidity can decrease, thereby the resonance point of the wall surface in common ink chamber 8 can further shift to low-frequency band.Therefore, for driving frequency and the resonant frequency that prevents ink jet print head is complementary, must be set and can be subjected to more harsh restriction the drive condition of ink jet print head.

Especially under the situation of line-type ink-jet recording head, can produce very big pressure and change, and cause above-mentioned inconvenience with big flow nozzle and long common ink chamber.

On the other hand, according to this embodiment of record head, pressure absorption component 21 is not made of thin part 22 fully, but by thin part 22 with constitute than the compound mode of thickness portion 23.For this reason, can when obtaining the pressure buffer effect, suppress the reduction of resonant frequency of the wall surface in common ink chamber 8.Therefore, even in, also can obtain stable droplet ejection characteristics with the high-speed driving ink jet print head.

Figure 13 is used to explain the curve map of the frequency characteristic that the pressure in common ink chamber 8 of first kind of embodiment of record head changes.In Figure 13, the longitudinal axis is represented the pressure (kPa) in common ink chamber 8 of first embodiment of record head, and transverse axis is represented frequency (kHz).Figure 13 represents the frequency characteristic at such situation: the thin part 22 on the two ends of the direction X of the pressure receiving surface 21a of pressure absorption component 21 in Fig. 6 accounts for 35% of the pressure receiving surface 21a gross area, and accounts for remaining 30% of the pressure receiving surface 21a gross area than thickness portion 23.By to comparing at Figure 13 of this first embodiment with at Figure 12 of the first above-mentioned comparative example, find out easily, the pressure absorption component 21 of this first embodiment can obtain higher pressure buffer effect, even the rigidity of the pressure absorption component 21 of first comparative example is smaller.

As shown in Figure 6, this of record head first embodiment is along the two ends of direction X abutment pressure absorption component 21.But, since pressure absorption component 21 be subjected to supporting base end portion near thickness compare with the thickness of the other parts of pressure absorption component 21 and reduced, in other words, pressure absorption component 21 has reduced, therefore can make that the deformation quantity of pressure absorption component 21 is very big generally compared with the rigidity of the other parts of pressure absorption component 21 by near the supporting base end portion rigidity.Therefore, though the local thickness that has increased pressure absorption component 21, and the slightly degeneration on the part that has increased thickness of the original function of pressure absorption component 21, the degeneration of the original function of pressure absorption component 21 has obtained inhibition on the whole.The degeneration of available original function with pressure absorption component 21 is suppressed to minimum, so that this degeneration can be ignored.

What be subjected to when in addition, two of common ink chamber 8 ends produce pressure resonance in common ink chamber 8 has the greatest impact.For this reason, be arranged on the very big place, end of pressure variety, can obtain the pressure buffer effect effectively by the thin part 22 that will have big pressure assimilation effect.

And, make than thickness portion 23 along direction X to be in the middle body of pressure absorption component 21 and to make thin part 22 be in the simple structure such than the two ends of thickness portion 22, in other words, have only two kinds of thickness, pressure absorption component 21 is produced easily.Though pressure absorption component 21 has simple structure, but can improve buffering effect.

And the pressure absorption component 21 with non-homogeneous thickness can be realized by laminated construction.In other words, availablely constitute laminated construction by ground floor 21A and second layer 21B, wherein ground floor 21A constitutes thin part 22, and second layer 21B is formed on ground floor 21A and goes up and constitute than thickness portion 23 with ground floor 21A.Such laminated construction can form by simple technology.According to this first embodiment, thin part 22 is made of one deck (ground floor 21A), and constitute by two-layer (first and second layers 21A and 21B), but constitute thin part 22 and be not limited in this than each the quantity of layer in the thickness portion 23 than thickness portion 23.For example, thin part 22 can be made of independent one deck, and can constitute by three layers than thickness portion 23.

If make the length that approaches part 22 of pressure absorption component 21 longer on direction X, then can obtain high pressure buffer effect, but because the vibration of pressure receiving surface 21a, in other words, the vibration of pressure absorption component 21 can produce pressure and change under lower frequency.On the other hand, if make the length that approaches part 22 of pressure absorption component 21 shorter on direction X, the vibration of pressure receiving surface 21a is improved, but the pressure buffer effect can descend.In view of the above,, can choose the coefficient of elasticity etc. of the size of pressure absorption component 21 and thickness, material, with the pressure buffer effect that obtains expectation and the vibration of pressure receiving surface 21 according to actual conditions according to present embodiment.In addition, can select coefficient of elasticity of the material of pressure absorption component 21 etc., so that vibration the best of pressure buffer effect and pressure receiving surface 21a.

The inventor has produced the sample of this first embodiment of the record head that uses different pressure absorption components 21 and header structure.The sample of 32 types ink jet print head of table 1 expression made is carrying out at each sampling under the situation of following assessment, and they have all been carried out the ink-jet test.Assessment A carries out at assessing the phase mutual interference, that is, whether pressure absorption component 21 has brought into play effect fully.Assessment B carries out at assessment frequency compliance, that is, whether the resonance of pressure absorption component 21 has influenced characteristics of inkjet.

Table 1

Sample number into spectrum	K value (* 10)	Assessment A	Assessment B
Sample number into spectrum	K value (* 10)	Assessment A	Assessment B	???????1	????0.02	????○	????×
???????2	????0.18	????○	????×	???????1	????0.02	????○	????×
???????2	????0.18	????○	????×	???????3	????1.04	????○	????×
???????4	????1.58	????○	????×	???????3	????1.04	????○	????×
???????4	????1.58	????○	????×	???????5	????1.65	????○	????×
???????6	????1.76	????○	????×	???????5	????1.65	????○	????×
???????6	????1.76	????○	????×	???????7	????2.14	????○	????○
???????8	????2.2	????○	????○	???????7	????2.14	????○	????○
???????8	????2.2	????○	????○	???????9	????2.81	????○	????○
???????10	????4.17	????○	????○	???????9	????2.81	????○	????○
???????10	????4.17	????○	????○	???????11	????4.76	????○	????○
???????12	????4.83	????○	????○	???????11	????4.76	????○	????○
???????12	????4.83	????○	????○	???????13	????4.83	????○	????○
???????14	????5.56	????○	????○	???????13	????4.83	????○	????○
???????14	????5.56	????○	????○	???????15	????7.66	????○	????○
???????16	????8.87	????○	????○	???????15	????7.66	????○	????○
???????16	????8.87	????○	????○	???????17	????9.11	????×	????○
???????18	????9.13	????○	????×	???????17	????9.11	????×	????○
???????18	????9.13	????○	????×	???????19	????13.4	????×	????×
???????20	????15.22	????○	????×	???????19	????13.4	????×	????×
???????20	????15.22	????○	????×	???????21	????22.4	????×	????○
???????22	????28.81	????○	????×	???????21	????22.4	????×	????○
???????22	????28.81	????○	????×	???????23	????42.26	????×	????×
???????24	????54.59	????○	????×	???????23	????42.26	????×	????×
???????24	????54.59	????○	????×	???????25	????62.92	????○	????×
???????26	????103.02	????×	????○	???????25	????62.92	????○	????×

????27	????137.89	???×	???○
????27	????137.89	???×	???○	????28	????172.21	???×	???○
????29	????222.62	???○	???×	????28	????172.21	???×	???○
????29	????222.62	???○	???×	????30	????711.84	???×	???○
????31	????1165.48	???×	???×	????30	????711.84	???×	???○
????31	????1165.48	???×	???×	????32	????2553.03	???×	???○

Assessment A be by be each sample of actual installation ink jet print head and print the assessment chart, to judge whether that having produced image abnormity in the sample of being printed carries out.In table 1, " zero " representative does not detect image abnormity by assessment A, and " * " representative has detected image abnormity by assessment A.On the other hand, assessment B is performed such: each sample self by ink jet print head sprays ink, changes driving frequency simultaneously, to observe the characteristics of inkjet such as jet speed, ink ejection amount and ink-jet curve (or ink-jet track).In table 1, on behalf of characteristics of inkjet, " zero " do not show the driving frequency compliance, and on behalf of characteristics of inkjet, " * " shown the driving frequency compliance.

And, chosen following project as the structure factor that can be considered to impact evaluation A and B.

SF1) the thickness Ud (m) of thin part 22;

SF2) thin part 22 is along the length Uy (m) of its minor face;

SF3) thin part 22 is along the length Ux (m) on its long limit (direction X);

SF4) the Young's modulus E (Pa) of thin part 22.

In following formula, the said structure factor is counted as variable, and a, b, c and d are counted as adaptation parameter (fitting parameters) and are optimized, thereby has obtained the parameter K of the performance of representative pressure absorption component 21.The value of this parameter K promptly refers to the K value in the table 1.

K＝Ud ^a×Uy ^b×Ux ^c×E ^d

We find that when preset parameter a, b, c and d were set at a=2, b=-2.5, c=-3.5 and d=2/3, the K value had suitably been expressed the performance of pressure absorption component 21.

As can be seen from Table 1, drop on about 2 * 10 when the K value ¹⁰To about 9 * 10 ¹⁰Scope within the time, assessment A and B are gratifying.

In other words, the rigidity and the resonant frequency that constitute the pressure absorption component 21 of pressure receiving surface 21a can be optimized, even so that under high driving frequency, also can obtain stable characteristics of inkjet for certain, this moment, thickness Ud (m), the thin part 22 of thin part 22 satisfied following relation (1) along the length Uy (m) of its minor face, thin part 22 along the length Ux (m) on its long limit (that is, along direction X) and the Young's modulus E (Pa) of thin part 22.

2×10 ¹⁰＜Ud ²×Uy ^-2.5×Ux ^-3.5×E ^2/3＜9×10 ¹⁰??———(1)

Along with the increase of the size (length) of the increase of nozzle 5 quantity and ink jet print head, the area of the pressure receiving surface 21a of pressure absorption component 21 increases.In this case, if use flexible material (such as resin) to make pressure absorption component 21, can in low-frequency band, produce the bigger resonance of pressure absorption component 21.In addition, because therefore the large-area flexible material of intractable preferably uses hard material to make pressure absorption component 21, some height slightly even rigidity of pressure absorption component 21 can become.Even when having used the material of high rigidity, also can obtain enough pressure assimilation effects for pressure absorption component 21.

The inventor surpasses 200 ink jet print head at the quantity of nozzle 5, for being the various materials that pressure absorption component 21 uses, has carried out the research of the resonance characteristics in common ink chamber 6.Figure 14 is used to explain the curve map of pressure resonance characteristics in the Young's modulus of pressure absorption component 21 of first embodiment of record head and common ink chamber 8.In Figure 14, the longitudinal axis is represented pressure resonance index, and transverse axis is represented the Young's modulus (MPa) of pressure absorption component 21.

For the degree that obtains to represent pressure resonance or the simple index number of scope, the driving frequency band of suppose ink jet print head be about 1kHz to about 16kHz, and to pressure the pressure when resonance produces changes and sues for peace.Like this, can have the degree of pressure resonance of pressure absorption component of different Young's or the index of scope compares to expression.For example, under the situation of frequency characteristic shown in Figure 13, resonance point is present on the frequency of 4kHz, 10kHz and 10.8kHz, and the change value of pressure on these three resonance points is respectively 0.8,1.1 and 0.5.Like this, can try to achieve the degree of expression pressure resonance and the index of scope by 0.8+1.1+0.5=2.4.In this manual, will call " pressure resonance index " to the degree of representative pressure resonance or the index of scope.

As can be seen from Figure 14, when the Young's modulus of pressure absorption component 21 became less than 100MPa, pressure resonance index increased rapidly.In other words, the variation of the pressure in common ink chamber 8 is more prone to influence characteristics of inkjet.In view of the above, the material that is preferably used in pressure absorption component 21 has 100MPa or bigger Young's modulus.

By using Young's modulus to be 100Pa or bigger material for the pressure absorption component 21 that constitutes pressure receiving surface 21a, when the quantity of nozzle 5 increases and the size of ink jet print head when becoming big, because the area of pressure receiving surface 21a is big, so can suppress the resonant frequency step-down.For this reason, even have at ink jet print head under the situation of a large amount of nozzle 5 and very big (or very long), also can obtain stable characteristics of inkjet.

Nickel (Ni) is suitable for making pressure absorption component 21, because the Young's modulus of nickel is about 150MPa.In other words, nickel satisfies the requirement that above-mentioned conduct is used for the material of pressure absorption component 21, and is easy to the processing processing.

Along among the total length Tx of direction X, the length Ux of thin part 22 is very important at pressure absorption component 21.If thin part 22 proportion in pressure absorption component 21 reduces, can't obtain sufficient pressure assimilation effect.This is that variation has taken place the structure buffer capacity that approaches part 22, and has become the pressure that can not fully absorb common ink chamber 8 generally because when elongated than thickness portion 23.On the other hand, if thin part 22 proportion in pressure absorption component 21 has increased, the vibration of pressure absorption component 21 can cause aforesaid problem.

The inventor is by changing thin part 22 has prepared this first embodiment of record head along the length Ux of direction X and pressure absorption component 21 along the total length Tx of direction X sample, and the characteristics of inkjet of these samples is assessed.Provided assessment result in the table 2, wherein NG represents that assessment result is unsatisfied with (bad), and OK represents that assessment result is satisfactory.

Table 2

Sample number into spectrum	????Ux/Tx	Assessment result
Sample number into spectrum	????Ux/Tx	Assessment result	???????1	?????0.061	??????NG
???????2	?????0.121	??????NG	???????1	?????0.061	??????NG
???????2	?????0.121	??????NG	???????3	?????0.182	??????NG
???????4	?????0.242	??????NG	???????3	?????0.182	??????NG
???????4	?????0.242	??????NG	???????5	?????0.303	??????OK
???????6	?????0.317	??????OK	???????5	?????0.303	??????OK
???????6	?????0.317	??????OK	???????7	?????0.343	??????OK
???????8	?????0.364	??????OK	???????7	?????0.343	??????OK
???????8	?????0.364	??????OK	???????9	?????0.424	??????OK
???????10	?????0.485	??????NG	???????9	?????0.424	??????OK

The assessment result that provides from table 2, the length Ux of the thin part 22 of pressure absorption component 21 and the ratio Ux/Tx of total length Tx are preferably disposed on about 0.25 and arrive within about 0.45 the scope.

In other words, can optimize the structure of pressure absorption component 21 by satisfying following relation (2), wherein Ux (μ m) refers to the length of thin part 22 along direction X, and Tx (μ m) refers to the total length of pressure absorption component 21 along direction X.Therefore, absorption pressure and inhibition resonance more definitely more definitely is to stablize characteristics of inkjet.

0.25＜Ux/Tx＜0.45????———(2)

Below, provide the explanation of revising embodiment according to first of record head ground, the present invention ground first embodiment with reference to Figure 15 and 16.Figure 15 is the plane that the basis first of first embodiment of expression record head is revised the pressure absorption component of embodiment.In Figure 15, those parts identical with appropriate section among Fig. 3 to 8 essence are used identical figure mark mark, and will dispense the explanation to them.Figure 16 is used to explain the curve map of the frequency characteristic that this first pressure of revising the common ink chamber of embodiment of first embodiment of record head changes.In Figure 16, the longitudinal axis is represented the pressure (kPa) in common ink chamber 8 of this first alter mode of first embodiment of record head, and transverse axis is represented frequency (kHz).First revise embodiment according to this of first embodiment of record head, the present invention is applied to ink jet print head.

First revise embodiment according to this of first embodiment of record head, pressure absorption component 21 has two thin parts 22 and one than thickness portion 23, but each thin part 22 has second within the zone that is arranged on thin part 22 than thickness portion 24.

By being provided with second, make the resonant frequency of wall surface in common ink chamber 8 shift towards high frequency band than thickness portion 24.For this reason, can further suppress resonance point produces in the ink-jet head driving frequency band.

In addition, by being provided with second than thickness portion 24, the intensity of thin part 22 has increased.As a result, become and be easy to processing more and produce ink jet print head.In Figure 16, solid line is represented the frequency characteristic that this first pressure of revising the common ink chamber of embodiment of first embodiment of record head changes.Usefulness as a comparison, chain-dotted line represent not to be equipped with second frequency characteristic that changes than the pressure in the common ink chamber 8 of first embodiment of the record head of thickness portion 24.And, the frequency characteristic that the pressure in the common ink chamber 8 of first comparative example of the ink jet print head of the pressure absorption portion 21 with thin part 22 thickness homogeneous shown in the dotted line presentation graphs 9 changes.

As can be seen from Figure 16, be equipped with second first to revise embodiment and have the pressure littler and change, and its pressure change and compare much smaller with first comparative example of ink jet print head than first embodiment of record head than this of first embodiment of the record head of thickness portion 24.

As a result, be equipped with second first to revise embodiment and have and gratifyingly change little characteristics of inkjet than not being equipped with second the ink jet print head pressure than thickness portion 24 than this of first embodiment of the record head of thickness portion 24.

Because can than thickness portion 24 resonant frequency of pressure absorption component 21 and the driving frequency of ink jet print head be separated by in the zone of the thin part 22 of pressure absorption component 21, being provided with second, so can obtain characteristics of inkjet stably effectively.And, during packaging technology, than being easier to handle ink jet print head, and production efficiency is improved, because, the intensity of pressure absorption component 21 is improved by being provided with second than thickness portion 24.

If make with identical than the thickness of thickness portion 24 with second, then can form simultaneously than thickness portion 23 and second than thickness portion 24 than thickness portion 23.In this case, production technology can obtain simplifying, and production cost is reduced.

Below, provide according to second of first embodiment of record head of the present invention with reference to Figure 17 and to revise embodiment.Figure 17 is expression along this second sectional view of revising the part of embodiment perpendicular to first embodiment of the record head of the direction of nozzle arrangement direction intercepting.In Figure 17, those parts identical with appropriate section among Fig. 3 to 8 essence are used identical figure mark mark, and will dispense the explanation to them.Second revise embodiment according to this of first embodiment of record head, the present invention is applied to ink jet print head.

Second revise embodiment according to this of first embodiment of record head, as shown in figure 17, pressure absorption component 21 is arranged on the part of wall surface of the framing component 14 that constitutes common ink chamber 8.In this case, be preferably on the rear surface of pressure absorption component 21 cushion chamber 25 is set,, and cushion chamber 25 is communicated with atmosphere by atmosphere communication passage (not shown) so that pressure absorption component 21 can carry out displacement.Except by the obtainable effect of part that constitutes pressure absorption component 21 by oscillating plate 2, first embodiment of record head this second revise embodiment can obtain can be by the record head introduced above first embodiment and first embodiment first revise the effect that embodiment obtains.

According to ink jet print head of the present invention, the wall surface in common ink chamber is constituted pressure receiving surface, and the member that constitutes pressure receiving surface have inhomogenous thickness and/or the different a plurality of parts of rigidity.As a result, can in the rigidity of absorption component that keep-ups pressure, suppress the reduction of the resonant frequency of pressure absorption component, and the driving frequency of ink jet print head can be made to such an extent that be different from the resonant frequency of pressure receiving surface.For this reason, even when driving ink jet print head, also can obtain stable characteristics of inkjet with high driving frequency.

It is especially effective to be applied to the line-type ink-jet recording head according to ink jet print head of the present invention.In other words, the line-type ink-jet recording head has a large amount of nozzle (position), and the pressure absorption component is very big along the length of its vertical (direction X).Thereby under the situation of line style ink jet print head, the resonance meeting of the pressure absorption component self that be reduced by the present invention produces significantly.But by applying the present invention to the line-type ink-jet recording head, the pressure that absorbs the common ink chamber in the rigidity of absorption component that keep-ups pressure is varied to for possibility, even and under the situation of all fronts type ink jet print head that at the same time total length of the straight line on the recording medium is write down, also can obtain stable characteristics of inkjet.

Below, will provide the explanation of production according to the first method of first embodiment of record head of the present invention.

Use anaerobic adhesive will be bonded in as the stacked piezoelectric element of pressure conversion device on the supporting substrate of making by special stainless steel (SUS) (base substrate 11), and use cast-cutting saw in piezoelectric element, to form groove, thus form separately so that with each pressurized China ink chamber 6 corresponding piezoelectric elements.To couple together with the side surface that forms reeded piezoelectric element 12 as the FPC cable 18 of conductor component by welding, urge the device unit with formation.

On the other hand, form to adopt nozzle plate 3 that electrocasting forms and oscillating plate 2 and constitute substrate (black cavity substrate) 1 by etching by the flow channel that silicon is made.With high accuracy nozzle plate 3, oscillating plate 2 and flow channel are constituted substrate 1 and position, and epoxy resin is coated on each composition surface, bond together so that nozzle plate 3, oscillating plate 2 and flow channel are constituted substrate 1 with stacked.The top surface that will urge the piezoelectric element 12 of device unit by epoxy adhesive bonds on the rear surface of oscillating plate 2.

Preparation is used to constitute the framing component 14 that the resin in common ink chamber 8 is made, this common ink chamber 8 is 35mm along the length on its long limit, length along its minor face is 1mm, and the degree of depth is 2mm, and by anaerobic adhesive this framing component 14 is bonded on the end surface of the rear surface of oscillating plate 2 and base substrate 11, thereby constitute ink jet print head.

The opening that constitutes common ink chamber 8 in the framing component 14 is covered by oscillating plate 2.Employed oscillating plate 2 has the 2 layer laminate structures that form by the Ni electroforming, and the two-layer thickness that has 3 μ m and 27 μ m respectively of laminated construction.The part of the opening of oscillating plate 2 cover framework members 14, promptly, cover the part in common ink chamber 8, have by two-layer form and thickness be 30 μ m (=3 μ m+27 μ m) in order to constitute than the middle body of thickness portion 23 and to be end that one (thinner) layer of 3 μ m constitutes along the both sides that vertically are positioned at middle body in common ink chamber 8 and by thickness.

The ink jet print head of producing in the manner described above and have 200 nozzles 5 (that is, adding up to 200 nozzle 5) is installed on the printer, and prints test.The result of printing test proves, can realize satisfied printing, and can not produce the image quality that is worsened, even when by also being like this when all nozzles 5 injection inks are repeatedly printed.

Usefulness has as a comparison made that to have by thickness be the ink jet print head of the oscillating plate that is sealing common ink chamber 82 that constitutes of independent one (thinner) layer of 3 μ m.In addition, this ink jet print head is installed on the printer, and prints test.The result of printing test proves, has produced the picture quality that is worsened by printing.

Therefore proof has been improved characteristics of inkjet by this first embodiment according to record head of the present invention.

Below, will provide the explanation of production according to the second method of first embodiment of record head of the present invention.

Preparation is used to constitute the framing component 14 that the resin in common ink chamber 8 is made, this common ink chamber 8 is 63mm along the length on its long limit, length along its minor face is 2.5mm, and the degree of depth is 3mm, and by anaerobic adhesive this framing component 14 is bonded on the end surface of the rear surface of oscillating plate 2 and base substrate 11, thereby constitute ink jet print head.

The opening that constitutes common ink chamber 8 in the framing component 14 is covered by oscillating plate 2.Employed oscillating plate 2 has the 3 layer laminate structures that form by the Ni electroforming, and first to the 3rd layer, that is, three layers of laminated construction have the thickness of 3 μ m, 15 μ m and 15 μ m respectively.The part of the opening of oscillating plate 2 cover framework members 14, promptly, cover the part in common ink chamber 8, have by first to the 3rd layer form and thickness be 33 μ m (=3 μ m+15 μ m+15 μ m) in order to constitute than the middle body of thickness portion 23 and to be the end of first and second layers of formation of 18 μ m (3 μ m+15 μ m) along the both sides that vertically are positioned at middle body in common ink chamber 8 and by thickness.

The ink jet print head of producing in the manner described above and have 360 nozzles 5 (that is, adding up to 360 nozzle 5) is installed on the printer, and prints test.The result of printing test proves, can realize satisfied printing, and can not produce the image quality that is worsened, even when by also being like this when all nozzles 5 injection inks are repeatedly printed.

Therefore, also proved in this case, improved characteristics of inkjet by this first embodiment according to record head of the present invention.

Below, provide explanation with reference to Figure 18 and 19 according to first embodiment of imaging device of the present invention.Figure 18 is the stereogram of this first embodiment of expression imaging device, and Figure 19 is used to explain the side view of a part of imaging device shown in Figure 18.This of imaging device first embodiment has adopted first embodiment according to carrier of the present invention.

Imaging device shown in Figure 18 and 19, that is, ink jet recording device has held a printing mechanism 112 in main body 111.This printing mechanism 112 comprises: first and second of the carrier 123 that can in main body 111, move, first embodiment and first embodiment with above-mentioned record head along main scanning direction revise structure any in embodiment ink jet print head 124, be used for to the print cartridge 125 of ink jet print head supply ink etc.Paper feeding cassette shown in Figure 19 (or paper supply carriage) 114 removably is arranged on the bottom of main body 111, is adorning folded a plurality of recording mediums (in this case, being record-paper) 113 in this paper feeding cassette 114.Recording medium 113 can be put on the paper feeding cassette 114 from the front of ink jet recording device.The manual feed carriage 115 that is used for manually supplying recording medium 113 can close obsolete the time as shown in Figure 19 to be closed, and opens in the counterclockwise direction when in use.Printing mechanism 112 is at print image from the recording medium 113 of paper feeding cassette 114 or manual feed carriage 115 supplies, and printed recording medium 113 is withdrawn into going out on the paper carrier 116 on the dorsal part that is arranged on ink jet recording device.

In printing mechanism 112, carrier 123 is supported by main guide rod 121 and sub-guide rod 122, and can slide along main scanning direction.The sub-guide rod 121 and 122 of advocating peace is that the left side and the right plate that cross main body 111 are provided with.The ink jet print head 124 that is used for injection yellow (Y), cyan (C), pinkish red (M) and black (Bk) ink droplet is arranged on carrier, make nozzle arrange along the direction perpendicular to main scanning direction, and inkjet direction is downward direction.Certainly, the ink jet print head 124 that is used to spray Y, C, M and Bk ink also can form an independent stature assembly or a unit.With respect to ink jet print head 124, Y, C, M and Bk print cartridge 125 replacedly are provided with.

Print cartridge 125 has at an upper portion thereof and is used for and the opening that communicates substantially, has the opening that is used for to corresponding ink jet print head 124 ink supply in its underpart, and portion has and is used for porous or the cellular member that the people holds ink within it.The capillarity of porous or cellular member will be supplied to the ink of ink jet print head 124 to remain on the small negative pressure.

Certainly, replace being equipped with four ink jet print heads 124 that are used for Y, C, M and Bk, can also be equipped with an independent ink jet print head from its nozzle ejection Y, C, M and Bk ink.

The dorsal part of carrier 123 promptly, along the downstream of recording medium transporting direction, is supported by main guide rod 121 slidably.The front side of carrier 123 promptly, along the upstream side of recording medium transporting direction, is supported by sub-guide rod 122 slidably.For mobile carrier 123 on main scanning direction, cross-over connection the driving wheel 128 and the driven pulley 129 that are driven by main scanning motor 127 and is provided with a Timing Belt 130, and carrier 123 is fixed on this Timing Belt 130.Like this, by main scanning motor 127 forwards and reverse rotation, carrier 123 moves back and forth.

On the other hand, in order to be placed on the downside that recording medium on the paper feeding cassette 114 is transported to ink jet print head 124, as shown in figure 19, the conveying roller 135 and being used to that the outer surface of conveying roller 134 in conveying roller 134, the ejection that be provided with paper feed roller 131, the friction pad 132, the guiding elements 133 that is used for leader record medium 113 that are used for from paper feeding cassette 114 Seperating boxs supplies recording medium 113, is used for turnover box conveying recording medium 113 limits the end roller 136 of recording medium 113 and the supply angle of conveying roller 134.Conveying roller 134 is driven through gear mechanism by sub-scan module 137.

With the moving range of carrier 123 on main scanning direction as one man, being provided with receiving member 139 will carry the recording medium 113 of coming be directed to the downside of ink jet print head 124 from conveying roller 134.Along recording medium transporting direction,, be provided with the conveying roller 141 and the spur gear 142 that are used for conveying recording medium 113 on exit axis in the downstream of receiving member 139.And, also be provided with and be used for towards what go out that paper carrier 11 6 withdraws from recording medium 113 withdrawing from roller 143 and spur gear 144, constituted the exit path of recording medium 113 with guiding elements 145 and 146.

In record, when moving carrier 123, drive ink jet print head 124 in response to picture signal, thereby ink is ejected on the static recording medium 113, and write down a line along main scanning direction.Then, after having carried the recording medium scheduled volume, write down next bar line in the same way.When the rear end that receives end of record signal or expression recording medium 113 had arrived the signal of posting field, the record operation stopped and withdraws from recording medium 113.In this case, in each ink jet print head 124, the variation of the pressure in common ink chamber has roughly obtained absorption, and simultaneously, resonance has obtained inhibition, thereby has obtained not having the stable characteristics of inkjet of phase mutual interference.For this reason, can on recording medium 113, write down image with high picture quality.

When observing from the front of ink jet recording device, as shown in figure 18, on the position beyond the posting field, the right-hand member along the moving direction of carrier 123 is provided with recovery unit 147.Recovery unit 147 is repaired the ink-jet fault of ink jet print head 124 etc.Recovery unit 147 comprises pressing device, suction means and cleaning device.When being in, carrier 123 prints waiting state (in this state, with carrier 123 move to recovery unit 147 corresponding positions on) time, pressing device is provided with a lid on ink jet print head, so that nozzle remains moisture state, thereby prevent that ink is dry and hard and cause the ink-jet fault.During writing down, the ink irrelevant with record can be ejected in the pressing device, and be constant with the ink viscosity that keeps all nozzles, thereby keep stable characteristics of inkjet.

When ink-jet fault etc. had taken place, the nozzle of ink jet print head 124 was sealed by pressing device, and bubble etc. was drawn out through the pipeline (not shown) together with ink from the nozzle of ink jet print head 124 by suction means.Then, remove the ink stick on the nozzle surface, dust granule etc., with the ink-jet fault of getting rid of ink jet print head 124 etc. by cleaning device.The ink recovery of suction means sucking-off is to reclaiming in the China ink jar (not shown), and this recovery China ink jar is arranged on the bottom of main body 111.The ink that is reclaimed is taken in by the ink absorption member that reclaims in the China ink jar.

Therefore, this embodiment according to imaging device and carrier, can obtain stable characteristics of inkjet, even also be so in the high-speed driving ink jet print head because ink jet print head have first embodiment of foregoing ink jet print head and first embodiment first and second revise any one structure in embodiment.

Can constitute printer, facsimile equipment, copier, plotter, unit equipment or the like according to imaging device of the present invention.

In addition, can spray fluid except ink according to record head of the present invention, such as dna sample, resist, moulding material etc.Can be equipped with the record head of the fluid of such injection except ink according to carrier of the present invention and imaging device.

In addition, be not limited to piezo-electric type according to the pressure conversion device (or urging apparatus) of record head of the present invention and urge device, but can use each other the device that urges, urge the device that urges that device, heating power type urge device and use marmem such as electrostatic.

Below, provide explanation with reference to Figure 20 to 30 according to second embodiment of record head of the present invention.According to this second embodiment of record head, the present invention is applied to ink jet print head.

Figure 20 is expression along the sectional view according to the part of second embodiment of record head of the present invention perpendicular to the intercepting of the direction of nozzle arrangement direction.Figure 21 is the sectional view of expression along the part of second embodiment of the record head of nozzle arrangement direction intercepting.In addition, Figure 22 is the exploded perspective view of second embodiment of expression record head.In Figure 20 to 24, omitted the diagram of pressure absorption component, and this pressure absorption component is introduced in detail with reference to Figure 25 to 30.

As shown in figure 22, the nozzle record head has by flow channel and constitutes the laminated construction that substrate (black cavity substrate) 31, nozzle plate 38 and oscillating plate 36 are formed.On flow channel formation substrate 31, be formed with a plurality of pressurizeds China inks chamber 34, and nozzle plate 38 is provided with the nozzle 33 that a plurality of and corresponding pressurized China ink chamber 34 is communicated with.On oscillating plate 36, be provided with a plurality of piezoelectric elements 37, as the pressure conversion element.FPC cable 45 is electrically connected with piezoelectric element 37, is used to provide the driving signal.This FPC cable 45 is equipped with drive circuit (driver IC) 46, is used for applying drive waveforms for each piezoelectric element 37 selectively.Piezoelectric element 37 makes oscillating plate 36 be subjected to displacement with respect to the China ink of pressurized correspondingly chamber 34.In this embodiment, the rod piezoelectric element is to use diamond cutter to cut out, and has been divided into separately and one of pressurized China ink chamber 34 corresponding piezoelectric element 37.

Each pressurized China ink chamber 34 shown in Figure 22 is intercepted, as shown in figure 21.If necessary, the supporting member 41 shown in Figure 21 can be set.

According to picture signal (or imaging signal), provide the driving signal through FPC cable 45 to piezoelectric element 37 from driver IC 46.Like this, piezoelectric element 37 is subjected to displacement (that is, pucker ﹠ bloat) according to driving signal, and the displacement of piezoelectric element 37 has passed to oscillating plate 36.Internal pressure by suitable control pressurized China ink chamber 34 makes ink droplet 42 spray from respective nozzles 33.

Piezoelectric element 37 is arranged on the base substrate 32, and base substrate 32 is arranged on the framework 43 shown in Figure 20.Framework 43 is installed on the carrier (not shown) according to the main body of second embodiment of imaging device of the present invention.Second embodiment of imaging device can have the identical structure of first embodiment (that is, Figure 18 and the ink jet recording device shown in 19) with imaging device.FPC cable 45 is connected with the circuit (not shown) of imaging device, and the ink supply source (such as print cartridge) shown in Figure 20 is to chamber 34 ink supply of pressurized China ink.

Figure 23 is the sectional view that has amplified in proportion in common ink chamber 39 of second embodiment of the record head of the expression direction of arranging along nozzle 33 (that is, along pressurized China ink chamber 34 vertically) intercepting.According to this embodiment, be provided with two row nozzles 33 symmetrically.Figure 23 has omitted a row nozzle 33 and must illustrate, but has only provided ink jet print head half.

As shown in figure 23, the same with base substrate 32, flow channel constitutes substrate 31 and is arranged on the framework 43.Sealant 47 is also as bonding agent.Structure shown in structure shown in Figure 23 and Figure 20 to 22 is slightly different, but the part with identical function has been used identical icon to remember rower into to annotate.

Certainly, the structure of this second embodiment of record head is not limited to the structure shown in Figure 20 to 23.

In Figure 20 to 23, nozzle towards on illustrate, and inkjet direction is a direction upwards.Not excessive the actual ejection ink droplet is when carrying out ink mist recording on the recording medium such as paper, and in most cases ink droplet sprays vertically downward.Therefore, according to present embodiment, in the ink mist recording that carries out image, the nozzle that ink droplet can be from Figure 24 sprays vertically downward facing to the recording medium (such as paper) of horizontal feed.

Figure 24 is the reciprocal cross-section figure of second embodiment of the record head of the straight line A-A intercepting of expression in Figure 23.Thereby Figure 24 represents record head and is in nozzle 33 state that ink droplet 42 sprays vertically downward that faces down.Ink from ink supply source 44 is supplied to common ink chamber 39 through ink supply opening (connecting pipe) 48, and the pressurized China ink chamber 34 through communicating with common ink chamber 39 by ink-feed channel (communication means) 40 accordingly arrives each nozzle 33.Can be not used in the formation image with the nozzle that vertically is positioned at common ink chamber 39 1 ends 33 corresponding pressurized China ink chambeies 34, thereby thereby use this nozzle 33 as the false nozzle that is used to draw the ejection bubble along common ink chamber 39.In addition, the nozzle 33 on the two ends that vertically are positioned at common ink chamber 39 in common ink chamber 39 can be used as so false nozzle.

Figure 25 is the only sectional view of a part of expression second embodiment that comprises the record head shown in Figure 24 of common ink chamber 39 and ink supply opening 48, and the pressure absorption component is used to explain.In addition, for the usefulness that compares, Figure 26 be the expression comprise common ink chamber 39 and ink supply opening 48 record head first comparative example only a part schematic diagram, the pressure absorption component is used to explain.

In Figure 25, among the figure from left to right direction X be equivalent to common ink chamber 39 vertically, that is, and the direction that nozzle 33 (or pressurized China ink chamber 34) is arranged.Pressure absorption component 50 is arranged on common ink chamber 39 along at least one wall surface of direction X extension.Pressure absorption component 50 has constituted the padded surface that is used for by absorption of vibrations pressure.

In the zone 51 of direction X, pressure absorption component 50 is not set.Be not arranged on along direction X on two positions of 39 both sides, common ink chamber though be equipped with the zone 51 of pressure absorption component 50, the position in the quantity in such zone 51 and zone 51 is not limited to situation shown in Figure 25.

Compare with first comparative example shown in Figure 26, owing to be provided with the zone 51 that is not equipped with pressure absorption component 50, length is shorter longitudinally along it for the pressure absorption component 50 shown in Figure 25.Thereby, uprise as the rigidity of the pressure absorption component 50 of oscillating plate 36, thereby the resonant frequency of pressure absorption component 50 shifts to high frequency band.Like this, resonant frequency and the driving frequency band that is present in the ink jet print head in the low-frequency band can be separated, change the ink-jet fault that causes with the pressure that prevents to cause owing to resonance.But under the situation of first comparative example shown in Figure 26, pressure absorption component 50 is vertically longer along it, thereby makes that the rigidity of pressure absorption component 50 is lower, and resonance point shifts to low-frequency band, and this may cause resonant frequency and driving frequency to be complementary.

Figure 27 is used to explain the curve map of the frequency characteristic that the pressure in common ink chamber of second embodiment of record head changes.In Figure 27, the longitudinal axis is represented the pressure (kPa) in common ink chamber 39 of second embodiment of record head, and transverse axis is represented frequency (kHz).Figure 27 represents the assessment result to such situation: in Figure 25, common ink chamber 39 is in the total length of direction X, and about 25% of length forms the zone 51 that is positioned at along the two ends of direction X.By to Figure 27 with compare at the assessment result by shown in the dotted line among Figure 16 of first comparative example shown in Figure 26, availablely find out that according to this second embodiment, the frequency that produces resonance point has shifted to high frequency band greatly.Therefore, can be highly driving ink jet print head, and can increase the print speed of ink jet print head.

As shown in figure 25, be an independent continuous zone ideally according to the padded surface of the pressure absorption component 50 of this second embodiment, rather than be divided into a plurality of zones.If the padded surface of pressure absorption component 50 is divided into a plurality of zones, the rigidity of each isolated area uprises, and the pressure assimilation effect reduces.On the other hand, if the thickness of pressure absorption component 50 reduces, for example, reduce in order to suppress the pressure assimilation effect, then becoming is difficult to produce pressure absorption component 50, thus pressure absorption component 50 and therefore the output of ink jet print head can reduce.In other words, form independent continuum, an absorption pressure more effectively by padded surface with pressure absorption component 50.

In addition, as shown in figure 25, the zone 51 that expectation will not be equipped with pressure absorption component 50 is arranged in the two ends in common ink chamber 39 along direction X.If zone 51 is arranged on other position, on the middle body of direction X, then the padded surface of pressure absorption component 50 will be divided into a plurality of zones such as common ink chamber 39, and the rigidity in the zone that separates uprises, thereby the pressure assimilation effect descends, as mentioned above.On the other hand, if only in common ink chamber 39 along arrangement region 51 on the end of direction X, then on that section that is equipped with zone 51, the pressure assimilation effect may be not enough, thereby cause local ink-jet failure.Therefore, expectation is arranged in common ink chamber 39 along on the two ends of direction X with zone 51.

Figure 28 is expression along the sectional view of revising embodiment perpendicular to first of second embodiment of the record head of the direction of nozzle 33 orientations intercepting.In Figure 28, those parts identical with appropriate section among Figure 20 to 25 have used identical figure mark to be marked, and have omitted the explanation to them.

In Figure 28, pressure absorption component 50 is by constituting for the layer with one deck with the layer that forms the oscillating plate 36 that is provided with at pressurized China ink chamber 34.In other words, as at the layer of the oscillating plate 36 in pressurized China ink chamber 34 also as pressure absorption component 50 at common ink chamber 39.

First revise embodiment according to this of second embodiment of record head, can form oscillating plate 36 and pressure absorption component 50 simultaneously, thereby production technology can access simplification.In general, be used as the pressure absorption component, the rigidity of oscillating plate is low excessively, thereby is easy to produce and the relevant problem that resonates.But, this that is applied to second embodiment by the basic structure with second embodiment of record head first revised embodiment, can suppress and the relevant problem of resonance, because the resonant frequency that can make pressure absorption component 50 fully shifts to high frequency band with respect to the driving frequency of ink jet print head.

But, the zone 51 that does not have pressure absorption component 50 can't be set in Figure 28.In other words, in Figure 28, oscillating plate 36 also is arranged on each pressurized China ink chamber 34 that is equivalent to zone 51, and constitutes whole ink jet print head in order to use with one deck structure, also the layer that constitutes oscillating plate 36 must be arranged on the common ink chamber 39, as pressure absorption component 50.

Figure 29 is the second only sectional view of a part that comprises common ink chamber 39 and ink supply opening 48 of revising embodiment of second embodiment of expression record head, and the pressure absorption component is used to explain.In Figure 29, those parts identical with appropriate section in Figure 25 and 28 have used identical figure mark to be marked, and have omitted the explanation to them.

To revise embodiment different with first of second embodiment among Figure 28, and this of second embodiment shown in Figure 29 second revised embodiment and be provided with the zone 51 that does not have pressure absorption component 50.More specifically, the layer that constitutes pressure absorption component 50 is formed on the whole common ink chamber 39, and fixed component 52 is arranged on the pressure absorption component 50 partly.Fixed component 52 suppresses the vibration of pressure absorption component 50, and plays the effect in zone 51.Like this, padded surface is made of the part of the pressure absorption component 50 that is not equipped with fixed component 52.Constitute fixed component 52 by a part, make and carry out under the situation of extra processing not needing, on absorption of vibrations member 50, form zone 51 and become possibility by pressure absorption component 50.

In Figure 28, pressure absorption component 50 and oscillating plate 36 can independently be made of the layer that separates.In this case, can form pressure absorption component 50, and this material does thinlyyer as the part of pressure absorption component 50, thereby form pressure absorption component 50 by material identical materials with the wall surface that forms common ink chamber 39.But in this case, form the material in common ink chamber 39, that is, form the material of framework 43, must make thinlyyer, absorb (buffering) function so that obtain pressure, the technology of difficulty forms pressure absorption component 50 thereby need more.For this reason, pressure absorption component 50 can be made by the resin such as polyamide, compares with the material that forms framework 43, and this resin has lower elasticity.By being that pressure absorption component 50 uses such resin, can produce the pressure absorption component by relative simple technology.

If attempt to increase the resonant frequency of pressure absorption component 50, then pressure assimilation effect itself can reduce.For this reason, expectation is optimized the shape of pressure absorption component 50, size, material etc., so that resonant frequency can fully shift towards high frequency band, does not cause characteristics of inkjet to be reduced to flagrant degree and the pressure assimilation effect can be reduced to.Therefore, the inventor has made the sample of second embodiment of 8 kinds of record heads, and these samples have different pressure absorption component 50 of structure and common ink chamber 39.Table 3 expression is to each following assessment A and C of carrying out in the sample of 8 kinds of ink jet print heads of the made of process ink-jet test.Assess A and assess the phase mutual interference, that is, whether pressure absorption component 50 has fully played effect.Assess C and assess ink-jet stability under the high driving frequency, that is, whether the resonance point of pressure absorption component 50 fully shifts to high frequency band.

Table 3

Sample number into spectrum	K1 value (* 10 ^-13)	Assessment A	Assessment C
Sample number into spectrum	K1 value (* 10 ^-13)	Assessment A	Assessment C	??????1	?????2.01	????○	????△
??????2	?????1.52	????○	????○	??????1	?????2.01	????○	????△
??????2	?????1.52	????○	????○	??????3	?????1.04	????△	????○
??????4	?????5.49	????×	????○	??????3	?????1.04	????△	????○
??????4	?????5.49	????×	????○	??????5	?????3.93	????○	????×
??????6	?????2.98	????○	????×	??????5	?????3.93	????○	????×
??????6	?????2.98	????○	????×	??????7	?????2.03	????○	????△
??????8	?????1.07	????○	????○	??????7	?????2.03	????○	????△

Assessment A be by be each sample of actual installation ink jet print head and print the assessment chart, to judge whether that having produced image abnormity in the sample of being printed carries out.In table 3, " zero " representative does not detect image abnormity at the assessment A of all nozzles 33 (or passage), " △ " representative at 10% or the assessment A of still less nozzle 33 (or passage) detected image abnormity, and " * " representative has detected image abnormity at the assessment A more than 10% nozzle 33 (or passage).On the other hand, assessment C is performed such: each sample self by ink jet print head sprays ink, changes driving frequency simultaneously, to observe all ink-jet stability.In table 3, " △ " represent 10% or the ink-jet stability of nozzle still less (or passage) lower, and that " * " representative surpasses the ink-jet stability of 10% nozzle (or passage) is lower.

And, chosen following project as the structure factor that can be considered to impact evaluation A and C.

SF11) common ink chamber 39 is along the total length of direction X;

SF12) pressure absorption component 50 is along the length L dx (m) of the buffering suface of direction X;

SF13) pressure absorption component 50 edges are perpendicular to the length L dy (m) of the buffering suface of the direction of direction X;

SF14) the thickness T d (m) of the pressure absorption component 50 of formation padded surface;

SF15) the elasticity Gd (Pa) of the pressure absorption component 50 of formation padded surface.

In following formula, said structure factor S F11 is counted as variable to SF15, and a1, b1, c1, d1 and e1 are counted as adaptation parameter and are optimized, thereby, obtained the parameter K 1 of the performance of representative pressure absorption component 50 by the pressure assimilation effect of consideration pressure absorption component 50 and the unfavorable effect or the side effect of resonant frequency.The value of this parameter K 1 promptly refers to the K1 value in the table 3.

K1＝Lx ^a1×Ldx ^b1×Ldy ^c1×Td ^d1×Gd ^e1

We find that when adaptation parameter a1, b1, c1, d1 and e1 were set at a1=-1, b1=1, c1=1, d1=-0.3 and e1=-1, the K1 value had suitably been expressed the performance of pressure absorption component 50.

As can be seen from Table 3, when the K1 value was big, the pressure assimilation effect of pressure absorption component 50 uprised, and is big but the unfavorable effect of the resonant frequency of pressure absorption component 50 or side effect become.When the K1 value drops on about 1.0 * 10 ^-13To about 2.0 * 10 ^-13Scope within the time, in other words, when following relation was met, assessment A and B were gratifying.

1.0×10 ^-13＜Lx ^-1×Ldx×Ldy×Td ^-0.3×Gd ^-1＜2.0×10 ^-13

Therefore, can prove from above-mentioned assessment result, second embodiment by adopting record head and first and second any structures of revising in the embodiments of second embodiment, even when carrying out high-speed record, also can obtain gratifying characteristics of inkjet, and, can write down image in the carrier of imaging device with high picture quality by such record head is set.

Below, will provide the explanation of production according to the first method of second embodiment of record head of the present invention.

Use anaerobic adhesive will be bonded in as the stacked piezoelectric element of pressure conversion device on the supporting substrate of making by special stainless steel (SUS) (base substrate 32), and use cast-cutting saw in piezoelectric element, to form groove, thus form separately so that with each pressurized China ink chamber 34 corresponding piezoelectric elements 37.To couple together with the side surface that forms reeded piezoelectric element 37 as the FPC cable 45 of conductor component by welding, urge the device unit with formation.

On the other hand, form to adopt nozzle plate 38 that electrocasting forms and oscillating plate 36 and constitute substrate (black cavity substrate) 31 by etching by the flow channel that silicon is made.With high accuracy nozzle plate 38, oscillating plate 36 and flow channel are constituted substrate 31 and position, and epoxy resin is coated on each composition surface, bond together so that nozzle plate 38, oscillating plate 36 and flow channel are constituted substrate 31 with stacked.The top surface that will urge the piezoelectric element 37 of device unit by epoxy adhesive bonds on the rear surface of oscillating plate 36.

Form common ink chamber 39, this common ink chamber 8 is 35mm along the length on its long limit, be 1mm along the length of its minor face, and the degree of depth is 2mm.Be made of resin framing component 43, this framing component 43 has the opening of the wide 1.2mm of long 20mm on the middle body of the wall surface that is arranged on common ink chamber 39.With thickness is the opening part that the polyamide resin of 20 μ m adheres to framework 43.By anaerobic adhesive this framing component 43 is bonded on the end surface of the rear surface of oscillating plate 36 and base substrate 32, thereby constitute ink jet print head.

The ink jet print head of producing in the manner described above is installed on the printer, and prints test.The result of printing test proves, can realize satisfied printing, and can not produce the image quality that is worsened, even when by also being like this when all nozzles 33 injection inks are repeatedly printed.

Usefulness has as a comparison made to have to stick on being of a size of 37mm * 2mm on the opening and being the ink jet print head of the polyamide resin that is provided with of the whole side surface for common ink chamber 39.In addition, this ink jet print head is installed on the printer, and prints test.The result of printing test proves, has produced the picture quality that is worsened by printing.

Therefore proof has been improved characteristics of inkjet by this second embodiment according to record head of the present invention.

Below, will provide the explanation of production according to the second method of second embodiment of record head of the present invention.

Form common ink chamber 39, this common ink chamber 8 is 63mm along the length on its long limit, be 2.5mm along the length of its minor face, and the degree of depth is 3mm.Be made of resin framing component 43, this framing component 43 has the opening of the wide 1.2mm of long 25mm on the middle body of the wall surface that is arranged on common ink chamber 39.By anaerobic adhesive this framing component 43 is bonded on the end surface of the rear surface of oscillating plate 36 and base substrate 32, make oscillating plate 36 cover the opening of framing component 43, thereby constitute ink jet print head.

In order to satisfy the image quality demand that further increases writing speed and further improve ink jet recording device institute document image, can increase the driving frequency of ink jet print head or increase the nozzle quantity of each ink jet print head.

But, when increasing the driving frequency of ink jet print head, because the reflection of the pressure of propagating to the common ink chamber from pressurized China ink chamber, the pressure in the pressurized China ink chamber can experience complicated behavior, is difficult to accurately spray ink droplet thereby become.On the other hand, when nozzle quantity was big, the common ink chamber had the shape that narrows down in the end longitudinally sometimes along it, so that spray the bubble in the common ink chamber with meeting the requirements.But because the shape that narrows down, the pressure the common ink chamber in changes along it and vertically becomes greatly towards the end, and to vertically big than middle body from its end along the common ink chamber of the influence of the pressure in the black chamber of pressurized.In other words, the pressure in pressurized China ink chamber is the difference according to each pressurized China ink residing position, chamber dynamically, and the pressure in all pressurized China ink chambeies of extremely difficult suitably control is dynamic.For this reason, expect that not only the pressure in the common ink chamber changes, and the pressure that expectation suppresses pressurized China ink chamber changes, no matter the present position in pressurized China ink chamber how.

In No. the 3069477th, Japan Patent, proposed a kind ofly to be used for suppressing the method that the pressure in the common ink chamber changes with what play air buffer in the common ink chamber by air cavity is set.In addition, in Japanese Laid-Open Patent Application 7-171969 number, proposed a kind of by use porous or cellular elastomeric material to absorb the method for the pressure that ink-jet produces at least a portion in black chamber.

Propose in Japanese Laid-Open Patent Application 9-141856 number, in the part in common ink chamber, cushion chamber is set, and between pressurized China ink chamber and energy generating unit branch, elastic component is set and blocks cushion chamber and common ink chamber, thereby use elastic component as buffer.In addition, propose in Japanese Laid-Open Patent Application 2000-301714 number, the elastic layer that comprises piezoelectric element is set in the common ink chamber, and piezoelectric element is driven absorption pressure by the pressure in foundation common ink chamber.

But, according to the method that proposes in No. the 3069477th, the Japan Patent, the air capacity in the air cavity can not be recovered by himself, thereby is difficult to keep for a long time buffering effect.Therefore, need constantly to control the air capacity of holding in the air cavity, in order to realize such control, need heating element heater, and in the time of in being used in the ink jet print head that urge device of use except heating power urges device, the method that is proposed is difficult to realize, cost is raise.And self control of air capacity is difficult in the air cavity, and the air of separating from air cavity may enter in the pressurized China ink chamber, thereby has stoped the pressure in pressurized China ink chamber fully to increase.As a result, in the worst case, the ink-jet failure may take place.

According to the method that proposes in Japanese Laid-Open Patent Application 7-171969 number, need extra technology that porous or cellular material are set, thereby the cost of ink jet print head raise.

In addition, according to the method that proposes in Japanese Laid-Open Patent Application 9-141856 number, need guarantee to be used for the enough big area of cushion chamber, to obtain enough buffering effects.But the result, the design freedom of common ink cavity shape is restricted, and is difficult to form the common ink chamber that can eject bubble thereby become with meeting the requirements.

And, according to the method that Japanese Laid-Open Patent Application 2000-301714 number proposes, be difficult to piezoelectric element control absorption pressure effectively, and must control module be set extraly and control piezoelectric element.Thereby the become cost of complexity more and ink jet recording device of the structure of ink jet recording device raises.

Thus, will provide the explanation according to the 3rd embodiment of record head of the present invention now, this record head has size and the cost that obtains reducing, and can improve characteristics of inkjet.

Provide the explanation of the 3rd embodiment of record head with reference to Figure 30 to 34.Figure 30 is the stereogram of the 3rd embodiment of expression record head.Figure 31 is the sectional view of the 3rd embodiment of the record head of the straight line A-A intercepting of expression in Figure 30, and the sectional view of the 3rd embodiment of the record head of the straight line B-B intercepting that Figure 32 is expression in Figure 30.In addition, Figure 33 is the exploded perspective view of the 3rd embodiment of expression record head, and Figure 34 is the stereogram that oscillating plate is observed from its basal surface shown in expression Figure 33.According to this 3rd embodiment of record head, the present invention is applied to ink jet print head.

Ink jet print head shown in Figure 30 to 33 comprises: the flow channel of being made by monocrystalline silicon (Si) constitutes substrate (black cavity substrate) 401, be arranged on oscillating plate 402 on the lower surface that flow channel constitutes substrate 401, be arranged on the nozzle plate 403 on the upper surface that flow channel constitutes substrate 401.Flow channel constitutes substrate 401, oscillating plate 402 and nozzle plate 403 and has constituted pressurized China ink chamber 406 and common ink chamber 408.Each nozzle that sprays ink droplet communicates with a pressurized China ink chamber 406 through nozzle passage 405, and this pressurized China ink chamber 406 has constituted flow channel.To pressurized China ink chamber 406 supply inks, communication means 409 has constituted the choked flow part through ink-feed channel (communication means) 409 in common ink chamber 408.

On outer surface one side of oscillating plate 402, that is, on a side opposite,, be provided with stacked piezoelectric element 412, as Pressure generator (or urging apparatus) at each pressurized China ink chamber 406 with pressurized China ink chamber 406.This piezoelectric element 412 is known electric mechanical conversion elements, and is fixed on the base substrate 413, and this base substrate 413 is made by the high rigidity material such as metal or pottery.

Between two adjacent pressurized China ink chambeies 406, be provided with spaced walls 401a.Be provided with support section 414 between the adjacent piezoelectric element 412 with on the corresponding position of spaced walls 401a.In this embodiment, piezoelectric element member has been carried out not cutting entirely (hemisection) cutting, forming the comb shape otch, thereby form a piezoelectric element 412, and constitute support section 414 by the tooth between two adjacent teeth that form piezoelectric element every a tooth of comb shape.Support section 414 has identical structure with piezoelectric element 412, and just support section 414 does not play piezoelectric element 412, because it is not applied driving voltage.

By bonding agent framing component 415 is arranged on the outer peripheral portion of oscillating plate 402.As shown in figure 33, on framing component 415, be formed with the groove part that constitutes common ink chamber 408.In addition, be formed with ink supply opening 416 on framing component 415, this ink supply opening 416 is supplied inks from the outside to common ink chamber 408.This ink supply opening 416 is communicated with ink supply source (not shown) such as print cartridge.For example, framing component 415 is made by epoxy resin or polyphenylene sulfurous acid fat (polyphenylene sulfite) by molding process.

By using the alkaline etching such as potassium hydroxide (KOH) solution, to have＜110〉crystal orientation monocrystalline silicon substrate carries out anisotropic etching, constitute at flow channel to have formed the hole that is used to constitute nozzle passage 405, pressurized China ink chamber 406 and ink-feed channel 407, groove etc. on the substrate 401.Certainly, also can use the material except silicon,, make flow channel and constitute substrate 401 such as stainless steel and photoconduction (or photosensitive) resin.

Oscillating plate 402 is made by metallic plate, and this metallic plate for example forms by electroforming process.According to present embodiment, oscillating plate is made by the nickel with 2 layers of structure (Ni) plate.But, the material except nickel such as other the laminated construction of metal, resin, metal and resin bed and the laminated construction of metal level, also is used to make oscillating plate 402.

Form on nozzle plate 403 and one of pressurized China ink chamber 406 corresponding each nozzle 404, these nozzles 404 have the diameter of about 10 μ m to about 35 μ m.Nozzle plate 403 can be made by the composition of composition, silicon or these materials of metal, metal and the resin such as polyimide resin film such as stainless steel and nickel (Ni).According to present embodiment, nozzle plate 403 is to be made by the nickel coating that adopts electroforming process to form.The interior shape of nozzle 404 (or inner wall shape) can be tubaeform, near cylindrical or approximate taper, makes that nozzle is that about 20 μ m are to about 35 μ m at the diameter of ink-jet side.In every row nozzle 404, nozzle 404 is to arrange with the spacing of 150dpi.

Nozzle surface (that is, ink is from the surface of its ejection) at nozzle plate 403 is formed with and scolds water layer, is not stained with ink to guarantee nozzle surface.Can adopt known method, scold water layer, on nozzle surface, form and scold water layer such as plating and coating.Curing after the evaporation of more specifically, PTFE-Ni eutectic plating, fluororesin ground electrolytic deposition, evaporation fluororesin and silicon-coating resin or the fluororesin solution can be used as known method and uses.By selecting to scold water layer, can stablize the shape and the characteristics of inkjet of ink droplet, and obtain high image quality according to ink composition and characteristic.

Piezoelectric element 412 has by replacing the laminated construction that stacked piezoelectric layer and inner electrode layer are formed.Piezoelectric layer is to be that about 10 μ m make to the lead zirconate titanate (PZT) of about 50 μ m by thickness, and inner electrode layer is to be that the silver-colored palladium (AgPd) of several μ m is made by thickness.In addition, inner electrode layer alternately is electrically connected with end electrode (outside or absolute electrode) and public electrode, and the driving signal is supplied to these electrodes through FPC cable 417.Pressurized China ink chamber 406 is made along with piezoelectric constant is the contraction of piezoelectric element 412 of d23 and expansion and convergent-divergent.Piezoelectric element 412 expands when the driving signal that it is applied is arranged and charges, and piezoelectric element 412 shrinks along opposite direction when electric charge discharges.

As shown in figure 33, common ink chamber 408 has in plane along the elongate rectangular shape of the orientation in pressurized China ink chamber 406 (or nozzle 404).The direction that arrange in this pressurized China ink chamber 406 is also referred to as the vertical of common ink chamber 408.

The oscillating plate 402 that constitutes the wall surface in pressurized China ink chamber 406 constitutes the part of the wall surface in common ink chamber 408.This part wall surface in the common ink chamber 408 that is formed by oscillating plate 402 is called free vibration surface 421.As shown in figure 34, wherein ignored the part that is connected with piezoelectric element 412, free vibration surface 421 comprises than thickness portion 422 and thin part 423.Have the flat shape that is roughly rectangle than thickness portion 422 and thin part 423, and be provided with band pattern along the longitudinal extension in common ink chamber 408.In this case, oscillating plate 402 has the laminated construction of three layers of composition, and is that by laminated construction whole three layers constitute than thickness portion 422, and thin part 423 only is to be made of the one deck in the laminated construction.Certainly, under the situation that thin part 423 is made of one deck, also can constitute by two-layer than thickness portion 422, perhaps, thin part 423 by two-layer situation about constituting under, can constitute by three layers than thickness portion 422.

When selectively with about 20V when the driving pulse voltage of about 50V imposes on the piezoelectric element 412 of the ink jet print head with said structure, the piezoelectric element 412 that has applied driving pulse voltage is subjected to displacement on each stacked direction of putting of piezoelectric element 412, thereby oscillating plate 402 on the direction of respective nozzle 404 deformation takes place.As a result, the volume or the capacity in corresponding pressurized China ink chamber 406 change, thereby the ink in this pressurized China ink chamber 406 has been applied pressure, and ink droplet is sprayed from respective nozzle 404, have realized ink mist recording.

Along with the ejection of ink, the ink pressure in the pressurized China ink chamber 406 reduces, thereby under the action of inertia of China ink stream, has produced small negative pressure in pressurized China ink chamber 406.In this state, when stopping when piezoelectric element 412 applies driving pulse voltage, promptly, when cutting off driving pulse voltage, oscillating plate 402 is returned to its initial position and pressurized China ink chamber 406 is returned to its original shape, and the result has produced negative pressure further in pressurized China ink chamber 406.Under this state, ink be able to through the common ink chamber 408 and the ink-feed channel 407 that constitutes the choked flow part be supplied to pressurized China ink chamber 406 from ink supply opening 409.Therefore, the vibration of the ink meniscus on nozzle 404 be suppressed and stable after, apply driving pulse voltage to piezoelectric element 412, spraying ink droplet, thereby realize ink mist recording next time.

When exerting pressure with the ejection ink droplet on pressurized China ink chamber 406, the pressure wave that produces in pressurized China ink chamber 406 has propagated in the common ink chamber 408 through ink-feed channel 407 and ink supply opening 409.But, in common ink chamber 408, because the effect of the thin part 423 on the free vibration surface 421 of the wall surface in formation common ink chamber 408, the pressure variation has obtained absorbing and cushioning.As a result, stop pressure wave reflection to go back to pressurized China ink chamber 406, thereby improved the controllability and the characteristics of inkjet of meniscus (meniscus).

The inventor has carried out numerical simulation at the 3rd comparative example of the wall surface with the common ink chamber 408 that is made of oscillating plate 403 self (only using than thickness portion 422) and this 3rd embodiment of record head with the wall surface in the common ink chamber 408 that is made of the free vibration surface 421 that comprises than thickness portion 422 and thin part 423.At the 3rd comparative example of record head and this 3rd embodiment, to the pressure in the pressurized China ink chamber 406 that is positioned at common ink chamber 408 middle bodies change and be positioned at common ink chamber 408 along its longitudinally the pressure in the pressurized China ink chamber 406 of end change and compare.

Supplying driving pulse voltage to piezoelectric element 412 with after being exerted pressure in corresponding pressurized China ink chamber 406, the virtual value that the pressure in the pressurized China ink chamber 406 of 20 μ s time durations changes is being asked average.We find, for the 3rd comparative example, the pressure in pressurized China ink chamber 406 that is positioned at the end in common ink chamber 408 changes than the situation that is positioned at common ink chamber 408 middle bodies larger about 15%, and this pressure variation greatly.On the other hand, we find, for the 3rd embodiment of record head, the pressure that is positioned at the end capacity compression China ink chamber 406 in common ink chamber 408 only changes situation than the middle body that is positioned at common ink chamber 408 larger about 2%, and this pressure changes smaller.Therefore, prove, make the pressure absorption efficiency be improved by forming free vibration surface 421 by thin part 423 with than thickness portion 422.

Be installed in this 3rd embodiment of the 3rd comparative example and record head on the printer respectively and carried out printing test.The result of printing test proves, when when spraying inks from all nozzles 404 and undertaken repeatedly printing by the 3rd comparative example, produced the image quality that descends.But on the other hand, we find, can realize satisfied printing by this 3rd embodiment of record head, and can not produce the image quality of decline, even when by also being like this when all nozzles 404 injection inks have carried out repeatedly printing.

Therefore, because at least a portion wall surface in common ink chamber 408 is to be made of the free vibration surface 421 that has than thickness portion 422 and thin part 423, therefore the pressure in common ink chamber 408 can be absorbed by thin part 422, and the rigidity and the intensity on the surface of free vibration simultaneously 421 can be by keeping than thickness portion 422.Owing to this reason, can adopt simple technology to produce ink jet print head.In addition, pressure in the common ink chamber 408 changes can access efficient buffer or absorption, and the controllability of meniscus and characteristics of inkjet can improve.The bubble ejection can also be improved, and the design freedom of ink jet print head can be improved.

In other words, by free vibration surface 421 is set in common ink chamber 408, the pressure in common ink chamber 408 can be reduced by the cushioning effect on free vibration surface 421.But owing to buffer capacity along with 421 attenuation of free vibration surface increase, therefore be preferably the thin free vibration surface 421 of whole wall surface setting in common ink chamber 408.But,, be difficult to form the large-area thin free vibration surface 421 of covering, and the intensity on so thin free vibration surface 421 may be not enough from the angle of processing and assembling.Therefore, this of record head the 3rd embodiment is provided with on free vibration surface 421 than thickness portion 422 and thin part 423, thereby can adopt simple technology to produce ink jet print head, free vibration surface 421 has enough intensity, can obtain the efficient buffer effect and can reduce pressure in the common ink chamber 408.

In this case, free vibration surface 421 and be arranged on the lip-deep oscillating plate 402 in pressurized China ink chamber 406 can be whole by forming with one deck, thereby reduced the quantity of the part of ink jet print head.Because oscillating plate 402 and free vibration surface 421 can be simultaneously by forming with a technology, quantity with production process and assembling procedure therefore can reduce production costs.This is because after having formed the part that constitutes pressurized China ink chamber 406 and having constituted the part in common ink chamber 408, the simple procedures of the layer that pressurized China ink chamber 406 and common ink chamber 408 can be by connecting and composing oscillating plate 402 and free vibration surface 421 forms.

By being free vibration surface 421 employing laminated construction, can pass through to constitute than this simple procedures formation of the number of plies that approaches part 423 than thin part 423 with respect to the number of plies change of formation than thickness portion 422.Can be by forming than thickness portion 422 by all layers (a maximum number of plies) of forming laminated construction, adopt simple operation to form vibration surface 421 to such an extent that have enough intensity.

Below, provide the introduction of revising embodiment according to first of the 3rd embodiment of record head of the present invention with reference to Figure 35 and 36.Figure 35 is first exploded perspective view of revising embodiment of the 3rd embodiment of expression record head, and the stereogram of the oscillating plate shown in Figure 36 Figure 35 that to be expression watch from the basal surface of oscillating plate.In Figure 35 and 36, those parts identical with appropriate section among Figure 30 to 34 essence are by identical figure mark mark, and have omitted the explanation to them.

The free vibration plate 421 of the wall surface in the formation common ink chamber 408 shown in Figure 35 has the thin part 423 that is arranged on its outer peripheral portion, as shown in figure 36 and be formed on island free vibration plate 421 core than thickness portion 422.

First of this 3rd embodiment of the 3rd comparative example and record head is revised embodiment to be installed on the printer respectively and to have carried out printing test.The result of printing test proves, when when spraying inks from all nozzles 404 and undertaken repeatedly printing by the 3rd comparative example, produced the image quality that descends.But on the other hand, we find, first of this 3rd embodiment by record head is revised embodiment can realize satisfied printing, and can not produce the image quality of decline, even when by also being like this when all nozzles 404 injection inks have carried out repeatedly printing.

Below, provide the introduction of revising embodiment according to second of the 3rd embodiment of record head of the present invention with reference to Figure 37 and 38.Figure 37 is second exploded perspective view of revising embodiment of the 3rd embodiment of expression record head, and the stereogram of the oscillating plate shown in Figure 38 Figure 37 that to be expression watch from the basal surface of oscillating plate.In Figure 37 and 38, those parts identical with appropriate section among Figure 30 to 34 essence are by identical figure mark mark, and have omitted the explanation to them.

The free vibration plate 421 of the wall surface in the formation common ink chamber 408 shown in Figure 37 has and is arranged on its outer peripheral portion the thin part 423 of two on each limit, as shown in figure 38, with the core that is formed on free vibration plate 421 with island than thickness portion 422, be formed within each thin part 423 and along between the adjacent thin part 423 of vertically separating in common ink chamber 408 than thickness portion 422.

Second of this 3rd embodiment of the 3rd comparative example and record head is revised embodiment to be installed on the printer respectively and to have carried out printing test.The result of printing test proves, when when spraying inks from all nozzles 404 and undertaken repeatedly printing by the 3rd comparative example, produced the image quality that descends.But on the other hand, we find, this of the 3rd embodiment by record head second revised embodiment and can be realized satisfied printing, and can not produce the image quality of decline, even when by also being like this when all nozzles 404 injection inks have carried out repeatedly printing.

Below, provide the introduction of revising embodiment according to the 3rd of the 3rd embodiment of record head of the present invention with reference to Figure 39 and 40.Figure 39 is the 3rd exploded perspective view of revising embodiment of the 3rd embodiment of expression record head, and the stereogram of the oscillating plate shown in Figure 40 Figure 39 that to be expression watch from the basal surface of oscillating plate.In Figure 39 and 40, those parts identical with appropriate section among Figure 30 to 34 essence are by identical figure mark mark, and have omitted the explanation to them.

As shown in figure 39, common ink chamber 408 is narrowing down towards end 40ga on the direction longitudinally perpendicular to it, thereby discharges bubble effectively.The free vibration plate 421 of the wall surface in the formation common ink chamber 408 shown in Figure 39 have in the shape relative set in common ink chamber 408 than thickness portion 422 and thin part 423.In other words, thin part 423 has the corresponding shape of shape in the end in common ink chamber 408 408a.

The 3rd of this 3rd embodiment of the 3rd comparative example and record head is revised embodiment to be installed on the printer respectively and to have carried out printing test.The result of printing test proves, when when spraying inks from all nozzles 404 and undertaken repeatedly printing by the 3rd comparative example, produced the image quality that descends.But on the other hand, we find, this of the 3rd embodiment by record head the 3rd revised embodiment and can be realized satisfied printing, and can not produce the image quality of decline, even when by also being like this when all nozzles 404 injection inks have carried out repeatedly printing.

By the width of free vibration plate 421 on the part that narrows down on the direction longitudinally perpendicular to common ink chamber 408 or near the thin part 423 of setting, can suppress and cushion the pressure variation in common ink chamber 408 effectively.In other words and since the buffer capacity of board member approximate with cube being directly proportional of its length, if free vibration plate 421 is the board members that not have than approaching part 423, then buffer capacity sharply descends on the part of free vibration plate 421 narrowed width.Therefore, by on the part of free vibration surface 421 narrowed width or near the thin part 423 of setting, can reduce the pressure in common ink chamber 408 effectively.

By narrowing down along the thin shape of part 423 of vertically making of common ink chamber 408 towards the end in common ink chamber 408, the flow velocity of ink can be improved, and the pressure in common ink chamber 408 can be reduced effectively, improve the ejection of bubble simultaneously.

In general, if the common ink chamber along vertical with its longitudinally the cross-sectional area that intercepts of direction reduce towards the end along the longitudinal and the width on free vibration surface also narrows down towards the end, then buffer capacity will reduce, thereby has increased the pressure in the common ink chamber.Therefore, the cross-sectional area that reduces the common ink chamber towards the end will influence the pressure in the common ink chamber greatly.

But according to this 3rd embodiment of record head, will than thin part 423 be arranged on free vibration plate 421 on the part of the position that the cross-sectional area in common ink chamber 408 reduces or near.Therefore, can reduce pressure in the common ink chamber 408.In addition, can improve ink flow rate by reducing the cross-sectional area of common ink chamber 408 towards the end.Therefore, common ink chamber 408 can be shaped when the pressure that suppresses common ink chamber 408 increases, bubble is sprayed with meeting the requirements.

Below, provide explanation with reference to Figure 41 and 42 according to the 3rd embodiment of imaging device of the present invention.Figure 41 is used to explain side view according to the part of the 3rd embodiment of imaging device of the present invention, and Figure 42 is the plane of the part of the imaging device shown in expression Figure 41.In this 3rd embodiment of imaging device, apply the present invention to ink jet recording device.In addition, this of imaging device the 3rd embodiment has adopted the 3rd embodiment according to carrier of the present invention.

In the ink jet recording device shown in Figure 41 and 42, carrier 703 is supported slidably by guide rod 701 and pillar 702, and guide rod 701 and pillar 702 cross a left side and the right plate (not shown) is fixing.Carrier 703 is moved along carrier scanning direction (main scanning direction) CSD through Timing Belt 705 by main scanning motor 704.

Carrier 703 comprises by four record heads 707 forms the ground head unit, and these four record heads 707 are used to spray Y, C, M and Bk ink.Each record head 707 has first to the 3rd any structure of revising in the embodiment of the 3rd embodiment and the 3rd embodiment of above-mentioned record head.The nozzle of record head 707 is arranged along the direction CSD perpendicular to main scanning direction, so that sprays Y, C, M and Bk ink downwards in Figure 41.

As shown in figure 41, contain Y, C, M and Bk ink and be arranged on the carrier 703 to the son of corresponding record head 707 supply Y, C, M and Bk inks jars 708.Though do not illustrate in Figure 41, Y, C, M and Bk ink are fed to son jar 708 through each ink supply Guan Congzhu jar (or print cartridge).

On the other hand, be provided with paper supply parts (such as paper feeding cassette 710) and supply recording medium 712, such as the paper that overlays on the stacked components 711.These paper supply parts comprise and being used for from separating and supply overlays the paper feed roller 713 of the recording medium 712 on the stacked components 711 and facing to the separating pad 714 of paper feed roller 713.Separating pad 714 is made by the big material of coefficient of friction, and applies load to paper feed roller 713.

Transfer unit will be transported to record head 707 belows from the recording medium 712 of paper supply parts supply.This transfer unit comprises: conveyer belt 712, and recording medium 712 sticks on this conveyer belt by electrostatic attraction, and is carried by this conveyer belt; Reverse rollers 722, the recording medium 712 that is used to carry the guide rail 715 between reverse rollers 722 and conveyer belt 721 to receive from paper-supply section; Conveying 723 is used for the recording medium 712 of almost vertical 90 degree conveyings is turned into along conveyer belt 721; With end pushing roller 725, should this roller be promoted towards conveyer belt 721 by pushing member 724.Charging roller 726 constitutes charging device, is used for the surface charging to conveyer belt 721.

Conveyer belt 721 is to be made of the belt that does not have end, and it is connected across on conveying roller 727 and the take-up roll 728.When conveying roller 727 by sub-scan module 731 when Timing Belt 732 and timing roller 733 rotates, conveyer belt 721 moves along the band direction of transfer BTD shown in Figure 42.

Conveyer belt 721 comprises front surface 721a and rear surface.Front surface 721a is formed from a resin, such as the EFTE pure material, through impedance Control and only have the thickness of about 40 μ m.This front surface 721a constitutes medium and adheres to (or absorption) surface, and recording medium 712 adheres on this surface.The rear surface is by making with front surface 721a identical materials, but is to use carbon to carry out impedance Control, thereby played the effect of interlaminated resistance or ground plane.

Charging roller 726 contacts the front surface 721a of conveyer belts 721, and rotates along with moving of conveyer belt 721.For example, apply the thrust of 2.5N at the two ends of the axle that carries charging roller 726.Conveying roller 727 also plays the effect of ground connection roller, and contacts with the rear surface (intermediate resistor layer) of conveyer belt 721, so that rear surface ground connection.

With the posting field of record head 707 accordingly, on the rear side of conveyer belt 721, be provided with guiding elements 736.Guiding elements 736 ground top surfaces protrude towards record head 707, are higher than the tangent line that connects conveying roller 727 and make the take-up roll 728 of conveyer belt 721.Therefore, the top surface that conveyer belt 721 is directed member 736 upwards promotes, and has been directed in the posting field of record head 707.

Being provided with paper delivery partly withdraws from by record head 707 and has write down record images medium 712.Paper delivery partly comprises the separating part that is used for recording medium 712 and conveyer belt 721 are separated,

exit roller

742 and 743 and go out paper carrier 744, and the recording medium 712 that is withdrawed from is deposited in this and goes out on the paper carrier 744.Two-sided paper supply unit 751 is removably disposed in back, ink jet recording device ground.This two-sided paper supply unit 751 will move upward and supply the recording medium 712 that before the recording medium 712 of turn-over its turn-over is returned the negative side and be sent to once more between reverse rollers 722 and the conveyer belt 721 by conveyer belt 721.

Recording medium 712 is one by one from the paper-supply section separation and supplies, and almost the recording medium 712 of vertical transport is guided by guide rail 715, and carries between conveyer belt 721 and reverse rollers 722 with the state that clamps.After this, the end of recording medium 712 is guided by conveying 723, and conveyer belt 721 by 725 ejections of end pushing roller, with about 90 degree of the throughput direction of upset recording medium 712.

Under the control of control circuit (not shown), be supplied to charging roller 726 from the alternating voltage of high voltage source (not shown), thereby positive output and negative output repeat alternately with respect to charging roller 726.Therefore, on conveyer belt 721, form alternately charge voltage distribution pattern, that is, on sub-scanning direction, had the distribution of charges pattern that alternately is charged to positive and negative polarity in the band shape of preset width.Sub-scanning direction is equivalent to the moving direction of conveyer belt 721.When recording medium supply to by this way the charging conveyer belt 721 on the time, recording medium 721 be polarized into conveyer belt 721 on the opposite electric charge of distribution of charges pattern, thereby formed shunt capacitance.As a result, recording medium 712 is attracted to and adheres on the conveyer belt 721, and when conveyer belt 721 moved, recording medium 712 was able to carry on sub-scanning direction.

When main scanning direction CSD moves carrier, according to picture signal activation record head 707, make ink droplet from each record head that is activated 707, be ejected on the static recording medium 712, to write down a line.After having carried the recording medium scheduled volume, write down next bar line in the same way.When the rear end that receives end of record signal or expression recording medium 712 had arrived the signal of posting field, the record operation stopped and recording medium 712 is withdrawn into out on the paper carrier 744.

In this case, in each ink jet print head 707, the pressure in common ink chamber changes and has obtained inhibition, thereby has obtained stable characteristics of inkjet, as top in conjunction with record head the 3rd embodiment and the 3rd embodiment first to the 3rd revise that embodiment introduces.For this reason, can on recording medium 712, write down image with high picture quality.

In addition, the present invention is not limited to these embodiments, under the situation that does not exceed scope of the present invention, can carry out various changes and modification.

Claims

1. record head comprises:

A plurality of nozzles that are used to spray fluid;

A plurality of pressurizeds chamber, they are arranged and communicate with one of respective nozzles separately along predetermined direction; With

Common cavity has a plurality of wall surfaces, and constitutes and be used for to pressurized chamber accommodating fluid,

In the wall surface of the common cavity of predetermined direction at least one has pressure receiving surface, and this pressure receiving surface has the rigidity that is lower than other wall surface, and constitutes and be used for absorption pressure and change,

Described pressure receiving surface is to be made of the pressure absorption component with non-homogeneous thickness.

2. according to the described record head of claim 1, wherein pressure receiving surface is divided into a middle body and is positioned at two end parts of middle body both sides along predetermined direction, and the pressure absorption component at the average thickness on the middle body greater than the average thickness of this pressure absorption component on end parts.

3. according to the described record head of claim 1, wherein the pressure absorption component has than thin part with than thickness portion, and these two parts have at least two kinds of thickness.

4. according to the described record head of claim 3, wherein be arranged on the pressure absorption component on the middle body of predetermined direction, and thin part is arranged on the middle body of pressure absorption component on the both sides of predetermined direction than thickness portion.

5. according to the described record head of claim 3, wherein the pressure absorption component has the laminated construction of forming by a plurality of layers, and the number of plies that constitutes than thin laminated construction partly is different from the number of plies of formation than the laminated construction of thickness portion.

6. according to the described record head of claim 3, satisfy relation

2×10 ¹⁰＜Ud ²×Uy ^-2.5×Ux ^-3.5×E ^2/3＜9×10 ¹⁰

Wherein Ud (m) expression is than thin thickness partly, and Uy (m) expression approaches the length of part edge perpendicular to the direction of predetermined direction, and Ux (m) expression approaches the length of part along predetermined direction, and E (Pa) represents thin Young's modulus partly.

7. according to the described record head of claim 1, wherein the pressure absorption component has 100MPa or bigger Young's modulus.

8. according to the described record head of claim 1, wherein the pressure absorption component is made by nickel.

9. according to the described record head of claim 3, satisfy relation

0.25＜Ux/Tx＜0.45

Wherein Ux (μ m) refers to the length of thin part along predetermined direction X, and Tx (μ m) refers to the total length of pressure absorption component along predetermined direction X.

10. according to the described record head of claim 2, wherein the end of pressure absorption component comprises and is arranged on second in its part than thickness portion.

11. according to the described record head of claim 10, wherein the pressure absorption component has identical thickness with second than thickness portion than thickness portion.

12., also comprise according to the described record head of claim 1:

Oscillating plate, at least one surface in formation pressurized chamber,

One of them layer forms at least a portion of described oscillating plate and pressure absorption component.

13. a line style record head comprises the record head described in claim 1.

14. a record head comprises:

A plurality of nozzles that are used to spray fluid;

Common cavity has a plurality of wall surfaces, and constitutes and be used for to pressurized chamber accommodating fluid; With

A plurality of pressure conversion devices are used to change the pressure within this pressurized chamber,

Have pressure receiving surface along at least one of predetermined direction in the wall surface of common cavity, this pressure receiving surface has the rigidity that is lower than other wall surface, and constitutes and be used for absorption pressure and change,

Described pressure receiving surface is to be made of the pressure absorption component with the different a plurality of parts of rigidity.

15. a line style record head comprises record head as claimed in claim 14.

16. a carrier comprises:

Record head as claimed in claim 1; With

Fluid box constitutes and is used for to the record head accommodating fluid.

17. a carrier comprises:

Record head as claimed in claim 14; With

Fluid box constitutes and is used for to the record head accommodating fluid.

18. an imaging device comprises:

Record head as claimed in claim 1;

Fluid box constitutes and is used for to the record head accommodating fluid,

Carrier is holding record head and fluid box, constitutes to be used for moving on perpendicular to the main scanning direction of predetermined direction.

19. an imaging device comprises:

Record head as claimed in claim 14;

Fluid box constitutes and is used for to the record head accommodating fluid,

20. a record head comprises:

A plurality of nozzles that are used to spray fluid;

A plurality of pressurizeds chamber, they are arranged and communicate with one of respective nozzles separately along predetermined direction;

Have padded surface along at least one of predetermined direction in the wall surface of common cavity, this padded surface has the rigidity that is lower than other wall surface, and constitutes and be used for by absorption of vibrations pressure,

Described padded surface is made of the pressure absorption component, and this pressure absorption component part has the zone that does not form padded surface, so that padded surface has extended less than the length of common ink chamber along the total length of predetermined direction along predetermined direction.

21. according to the described record head of claim 20, wherein the pressure absorption component has the continuous surface that constitutes padded surface.

22. according to the described record head of claim 20, wherein said zone is arranged in the wall surface of described common cavity along the two ends of at least one of predetermined direction

23. according to the described record head of claim 20, wherein:

At least a portion wall surface that constitutes the pressurized chamber has the rigidity that is lower than other wall surface, with the oscillating plate that constitutes pressure conversion device and

Oscillating plate and buffering surface all are to be made of shared ground floor.

24., also comprise according to the described record head of claim 23:

The second layer, part are formed on the shared ground floor, and constitute described zone,

Described shared ground floor extends along predetermined direction, and constitutes padded surface by its surface that does not form the second layer thereon.

25. according to the described record head of claim 20, wherein padded surface has the elasticity of other wall surface that is lower than common cavity.

26. according to the described record head of claim 20, the elasticity Gd (Pa) that wherein constitutes the pressure absorption component of padded surface satisfies relation

1.0×10 ^-13＜Lx ^-1×Ldx×Ldy×Td ^-0.3×Gd ^-1＜2.0×10 ^-13

Wherein Lx (m) expression common cavity is along the length of predetermined direction, Ldx (m) expression pressure absorption component is along the length of the buffering suface of predetermined direction, Lyx (m) expression pressure absorption component edge is perpendicular to the length of the buffering suface of the direction of predetermined direction, and Td (m) expression constitutes the thickness of the pressure absorption component of padded surface.

27. a carrier comprises:

Record head as claimed in claim 20; With

Fluid box constitutes and is used for to the record head accommodating fluid.

28. an imaging device comprises:

Record head as claimed in claim 20;

Fluid box constitutes and is used for to the record head accommodating fluid,

29. a record head comprises:

A plurality of nozzles that are used to spray fluid;

At least one wall surface of common cavity has the free vibration surface, and this free vibration surface has than thickness portion and thin part.

30. according to the described record head of claim 29, the member that wherein constitutes the free vibration surface constitutes the surface in pressurized chamber integratedly.

31. according to the described record head of claim 29, the member that wherein constitutes the free vibration surface has the laminated construction of being made up of a plurality of laminations.

32. according to the described record head of claim 30, wherein the thickness than thickness portion equates with the thickness of the member of the wall surface that constitutes the pressurized chamber.

33. according to the described record head of claim 29, wherein thin portion arranged on free vibration surface on the free vibration surface near the part narrower than other parts perpendicular to the width of the direction of predetermined direction.

34. according to the described record head of claim 29, wherein thin portion arranged is near the part that reduces than other parts along the cross-sectional area perpendicular to the common cavity of the direction intercepting of predetermined direction on the common cavity.

35., wherein reduce towards the end of common cavity along predetermined direction along cross-sectional area perpendicular to the common cavity of the direction of predetermined direction intercepting according to the described record head of claim 29.

36. a carrier comprises:

Record head as claimed in claim 29; With

Fluid box constitutes and is used for to the record head accommodating fluid.

37. an imaging device comprises:

Record head as claimed in claim 29;

Fluid box constitutes and is used for to the record head accommodating fluid,