Ink jet recording head

An ink-jet recording head includes an actuator and a nozzle guide. The actuator ejects ink through a plurality of nozzle apertures. Wiring substrate is connected to the actuator at a connection portion and transmits drive signals to the actuator through the connection portion to drive the actuator to eject ink. The nozzle guide covers an outer periphery of the actuator while exposing the nozzle apertures. The nozzle guide also covers the connection portion between the actuator and the wiring substrate so as to be out of physical contact with ends of the connection portion. The nozzle guide includes a positioning portion used to position nozzle guide with respect to the actuator during assembly. A manifold is connected to the actuator and supplies the ink to the actuator. Seal agent fills areas between the actuator and the nozzle guide, between the wiring substrate and the actuator, between the nozzle guide and the actuator, and between the actuator and the manifold. The seal agent covers the connection portion between the actuator and the wiring substrate, supports the wiring substrate in between the nozzle guide and the manifold, and surrounds the entire outer peripheral surface of the actuator.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an ink jet recording head mounted on an ink jet printer, and more particularly to an ink jet recording head having a nozzle guide for protecting the head portion.

2. Description of the Related Art

Ink jet printers record images on recording media, such as paper sheets. A typical ink jet printer includes a platen, a carriage, and a recording head unit. The platen is provided for supplying the recording media. The carriage is oscillatingly moved in parallel with the platen across the surface of the recording medium. The recording head unit is mounted on the carriage and includes an ink jet recording head. While the carriage scans across the surface of the recording media, the ink jet recording head ejects ink based on image data to record an image on the recording medium.

There are many types of ink jet recording heads that can be mounted in ink jet printers. One type is called a piezoelectric type. A piezoelectric type ink jet recording head includes an ink chamber formed from a piezoelectric element. Ink is held in the ink chamber. A voltage is applied to the piezoelectric element so that the ink chamber deforms. This deformation reduces the volume in the ink chamber so that an ink droplet is ejected out from a nozzle connected to the ink chamber. Lead zirconate titanate, commonly known as PZT, is used as the material for the piezoelectric element.

Piezoelectric type ink jet recording heads typically include a plurality of piezoelectric elements and ink chambers. An actuator is provided for controlling ejection of ink from the plurality of ink chambers. A wiring substrate is connected to the actuator in order to transmit drive signals to the actuator.

The various components of the ink jet recording head are not strongly connected together. Also, vaporized ink can contact the actuator, or where the various components are connected together, and degrade electrical characteristics or even cause short circuits. To prevent these problems, a nozzle guide is used to cover the outer peripheral surface of the actuator. An ink jet recording head fitted with the nozzle guide is attached onto a base plate of the carriage. Seal agent, such as a silicone type adhesive, is coated over the space between the nozzle guide and the base plate in order to prevent ink from entering through the space and contacting the actuator and other covered components.

SUMMARY OF THE INVENTION

However, with this conventional configuration, it is difficult to accurately position the cover guide with respect to the actuator when assembling the head. The head can be damaged or improperly assembled because of this. Further, when the actuator and the nozzle guide are being attached together, the nozzle guide can contact the outer ends of the wiring substrate where the wiring substrate is connected to the actuator. As a result, the wiring substrate can peel away from the actuator, so that electrical characteristic of the wiring substrate and continuity of the connection can be degraded. Still further, the space is open between the nozzle guide and the actuator, and there is a danger that ink will enter through the space, until the ink jet recording head is fixed onto the carriage and the seal agent is actually coated over the space. Because ink can enter through the space, it is not possible to supply ink to the actuator or perform ink-ejection tests with the supplied ink until the actuator is fixed in place and coated with seal on the carriage.

It is an objective of the present invention to provide an ink jet recording head that enables easy and proper assembly of the actuator with respect to the nozzle guide, without damaging the actuator portion of the head. It is another objective of the present invention to overcome the above-described problems and provide an ink jet recording head wherein ink can be supplied to the actuator before the actuator is mounted on the carriage, without fear that ink will cling to the actuator or to connection portions between various electrical components.

An ink-jet recording head according to one aspect of the present invention includes an actuator and a nozzle guide. The actuator ejects ink through a plurality of nozzle apertures. The nozzle guide covers an outer periphery of the actuator while exposing the nozzle apertures. The nozzle guide includes a positioning portion used to position nozzle guide with respect to the actuator during assembly.

With this configuration, the ink nozzle guide can be accurately positioned during assembly of the ink jet recording head.

The ink-jet head according to this aspect of the present invention can be manufactured using the following method. First, an actuator for ejecting ink through a plurality of nozzle apertures is prepared. Then a nozzle guide with a frame shape is formed, wherein the nozzle guide has a nozzle side and a positioning-portion side at opposite sides thereof. The nozzle guide is formed with a positioning portion in an edge portion of the positioning-portion side. Then a fixing member is abutted against the positioning portion to press the nozzle side of the nozzle guide against a flat surface while, according to operation of a slanting portion that is provided to at least one of the positioning portion of the nozzle guide and the fixing member, guiding the nozzle guide to a predetermined position. Then the actuator is inserted into the nozzle guide to cover an outer periphery of the actuator with the nozzle guide while exposing the nozzle apertures.

An apparatus for positioning a nozzle guide and an actuator according to this aspect of the present invention includes a flat surface, a fixing member, and an actuator-positioning unit. The fixing member presses against a positioning portion of the nozzle guide to press a nozzle side of the nozzle guide against the flat surface while, according to operation of a slanting portion that is provided to at least one of the positioning portion of the nozzle guide and the fixing member, guiding the nozzle guide to a predetermined position on the flat surface. The actuator-positioning unit positions the actuator in the nozzle guide so that the nozzle guide covers an outer periphery of the actuator while exposing nozzle apertures of the actuator.

According to another aspect of the present invention, an ink jet recording head includes an actuator, a wiring substrate, and a nozzle guide. The actuator ejects ink through a plurality of nozzle apertures. The wiring substrate has a connection portion connected to the actuator. The connection portion has ends that define outer extent of a connection range between the wiring substrate and the actuator. The wiring substrate transmits drive signals to the actuator through the connection portion to drive the actuator to eject ink. The nozzle guide covers the connection portion between the actuator and the wiring substrate. The nozzle guide is configured to be out of physical contact with ends of the connection portion.

With this configuration, the nozzle guide will not contact the wiring substrate while the nozzle guide is being attached to the actuator, so that the wiring substrate will not be snagged and peeled away from the actuator by the nozzle guide. Accordingly, the electrical characteristic of the wiring substrate will not be degraded by damage at its ends. Also, a non-continuous state at the connection portion caused by damage at the ends of the wiring substrate can be prevented.

According to another aspect of the present invention, an ink-jet recording head includes an actuator, a wiring substrate, a nozzle guide, a manifold, and seal agent. The actuator ejects ink through a plurality of nozzle apertures. The wiring substrate is connected to the actuator at a connection portion. The wiring substrate is for transmitting drive signals to the actuator through the connection portion to drive the actuator to eject ink. The nozzle guide covers the connection portion between the actuator and the wiring. substrate. The seal agent fills areas between the actuator and the nozzle guide and between the wiring substrate and the actuator, and also covers the connection portion between the actuator and the wiring substrate.

With this configuration, the seal agent prevents ink from seeping into the connection portion between wiring substrate and the actuator, even if ink is supplied to the actuator before the head is mounted onto a carriage. Moreover, even if the actuator16is made from lead zirconate titanate or other material that includes lead, the user can handle the actuator safely because no part of the actuator is exposed to contact by the user.

According to another aspect of the present invention, an ink-jet recording head includes an actuator, a wiring substrate, a nozzle guide, a manifold, and seal agent. The actuator ejects ink through a plurality of nozzle apertures. The wiring substrate is connected to the actuator at a connection portion. The wiring substrate is for transmitting drive signals to the actuator through the connection portion to drive the actuator to eject ink. The nozzle guide covers the connection portion between the actuator and the wiring substrate. The manifold is connected to the actuator and supplies the ink to the actuator. Seal agent fills areas between the nozzle guide and the actuator and between the actuator and the manifold. The seal agent supports the wiring substrate in between the nozzle guide and the manifold and surrounds an entire circumference of an outer peripheral surface of the actuator.

With this configuration, the actuator is completely encompassed by the seal agent between the nozzle guide and the manifold, so that ink will not come in contact with the actuator. Also, the ink-jet recording head is made as an independent head unit, so ink can be supplied to the actuator and ink ejection tests performed.

DETAILED DESCRIPTION OF THE EMBODIMENT

Next, an ink jet recording head11according to an embodiment of the present invention will be described while referring to the attached drawings. First, an ink jet printer1on which the ink jet recording head is mounted will be explained with reference toFIG. 1.

As shown inFIG. 1, the ink jet printer1includes a casing2and, disposed within the casing2, a platen roller3, a carriage10, a guide rod4, a guide member5, pulleys7and8, a belt9, and a carriage drive motor6.

The platen roller3is rotated by a line-feed motor (not shown) to transport a recording sheet P in the direction indicated by arrow A inFIG. 1. The guide rod4and the guide member5extend in parallel with the platen roller3. The carriage10is mounted on the guide rod4in confrontation with the platen roller3.

The pulley7is fixed to the shaft of a carriage drive motor6provided at the left end portion of the casing2as viewed inFIG. 1. The pulley8is provided at the right end portion at the inside of the casing2as viewed inFIG. 1. The belt9spans between the pulleys7and8. The carriage10is fixed to the belt9. With this configuration, oscillating drive force from the carriage drive motor6moves the carriage back and forth in parallel with the platen roller3as guided by the guide rod4and the guide member5.

The ink recording head11is mounted on the upper surface of the carriage10. The ink recording head11receives drive signals generated, based on image data, by a circuit board (not shown) and forms images on the surface of the recording sheet P by ejecting ink onto the recording sheet P based on the drive signals.

Next, the ink recording head11will be described in more detail with reference toFIGS. 2 through 6. The ink recording head11includes an actuator16, a pair of wiring substrates17a,17b, a pair of manifolds18, and a nozzle guide20.

The actuator16includes a center plate12, a pair of actuator substrates13a,13b, and a nozzle plate15. The center plate12is formed in a flat rectangular shape. The actuator substrates13a,13bare attached to either side of the center plate12by adhesive, so that the center plate12is sandwiched between the actuator substrates13a,13b. The pair of actuator substrates13a,13bare formed from a piezoelectric material made from lead zirconate titanate, commonly known as PZT, to a rectangular shape that is large enough to substantially cover the lower portion of the center plate12. The surfaces of the actuator substrates13a,13bthat face the center plate12are formed with ink channels.

As can be seen inFIG. 4, the nozzle plate15has an elongated rectangular shape and is formed with two nozzle rows14a,14bthat extend in the lengthwise direction of the nozzle plate15. The nozzle plate15is attached to the lower end, that is, as viewed inFIG. 6, of the connected center plate12and actuator substrates13a,13b. An intimate seal with no gaps is developed between the nozzle plate15and the actuator substrates13a,13b. The outlet port of each ink channel in the actuator substrates13a,13bis in fluid communication with a corresponding one of the two nozzle rows14a,14bformed in the nozzle plate15so that operation of the actuator substrates13a,13bejects the ink in the ink channels of the actuator substrates13a,13bout through the nozzles of the nozzle rows14a,14b.

As can be seen inFIG. 6, the rear-side end of the wiring substrate17ais connected by soldering to the substantial center of the front-side surface of the actuator substrate13b, which is the opposite surface from the surface connected to the center plate12. The front-side end of the wiring substrate17bis connected by soldering to the substantial center of the rear-side surface the actuator substrate13a, which is the opposite surface from the surf ace connected to the center plate center plate12. The solder connections between the wiring substrates17a,17band the actuator substrates13a,13bextend in parallel with the nozzle plate15. The wiring substrates17a,17bare made from a flexible resin, such as polyimide, into an elongated thin plate that is printed with wiring. Although not shown in the drawings, a circuit board for generating drive signals is connected to the other end of the wiring substrates17a,17b. The wiring substrates17a,17bserve to transmit the drive signals to the actuators16so that the actuators16can be driven.

Each manifold18is connected by adhesive to the upper surface of the corresponding one of the actuator substrates13a,13b, that is, to the surface that is opposite from the surfaces of the actuator substrates13a,13bthat are connected to the nozzle plate15. The manifolds18supply ink to the ink channels formed in the actuator16. The manifolds18are provided with two ink supply tubes18a,18bconnected to the ink channels of the actuator substrates13a,13bso that ink supplied from an external ink supply source to the supply tube18aflows into the ink channel group of the actuator substrate13aand ink supplied to the ink supply tube18bflows into the ink channel group of the actuator substrate13b.

The nozzle guide20has a rectangular frame shape. The nozzle guide20is attached by seal agent19aand optically-cured adhesive19bto the actuator16so as to cover the outer peripheral surface of the actuator16, with the exception of the end surfaces of the actuator16that are connected to the nozzle plate15and to the manifolds18. The seal agent19ais a silicone type adhesive having electrically insulating properties, waterproofing properties, and adhesive properties. The optically-cured adhesive19bis for temporarily fixing the nozzle guide20to the actuator16. The nozzle guide20prevents ink vapor, which is formed during ejection of ink from the nozzle rows14a,14b, from contacting the actuator16and also prevents the actuator substrates13a,13band the wiring substrates17a,17bfrom pulling apart when the connection portion between the actuator substrates13a,13band the wiring substrates17a,17bis pulled on for some reason. The nozzle guide20will be described in further detail later. Although not shown in the drawings, a nozzle protector for protecting the ink recording head11is provided on the carriage10. The nozzle protector is made from a combination of plastic and rubber and has an inner shape that matches the outer shape of the nozzle guide20. When the ink recording head11is mounted in the nozzle protector, the fit between the inside of the nozzle protector and the outside of the nozzle guide will position the ink recording head11.

Seal agent19ais coated on the portions of the actuator substrates13a,13bin the gap between the nozzle guide20and the nozzle plate15and in the gap between the nozzle guide20and the manifolds18, on the connection portion between the actuator substrates13a,13band the wiring substrates17a,17b, and on the portion of both surfaces of each wiring substrate17a,17bnear these other coated areas. Optically-cured adhesive19bis coated between the nozzle guide20and the actuator16to temporarily fix the nozzle guide20to the actuator16. By coating these areas with the seal agent19aand optically-cured adhesive19b, the actuator16and the wiring substrates17a,17bcan be protected from being contacted by vaporized ink. Accordingly, degradation of electrical characteristics and short circuits caused by ink directly contacting the actuator16and the wiring substrates17a,17bcan be reliably prevented. It should be noted that the optically-cured adhesive19bitself has no waterproofing properties, so the seal agent19ais coated in the vicinity of the optically-cured adhesive19bin order to prevent ink from penetrating through the optically-cured adhesive19b.

Next, a detailed explanation will be provided for the nozzle guide20while referring toFIGS. 7 to 12. The nozzle guide20is a rectangular shaped member formed from a resin material. The nozzle guide20is attached to the actuator16so as to cover the outer peripheral surface of the actuator16. The nozzle guide20includes a frame portion22, wall portions20a,20b, and protrusion portions25a,25b,25c,25d, all formed integrally together from the resin material.

As best viewed inFIG. 9, the frame portion22has a rectangular frame shape that defines an opening26with its inner surface. The frame portion22includes two confronting long sides22a,22band two confronting short sides22c,22d. The two short sides22c,22dare sandwiched between ends of the long sides22a,22b.

The wall portions20a,20bare formed integrally with the long sides22a,22b, respectively, of the frame portion22in an upright thin plate shape with the same thickness as the corresponding long side22a,22bshown inFIG. 9. The wall portions20a,20bextend upward from the long sides22a,22b, respectively. More specifically, the wall portion20ais formed on top of the long side22aas shown inFIG. 7and the wall portion20bis formed on top of the long side22bas shown inFIG. 10. Accordingly, as shown inFIGS. 10 and 12, the upper edges of the wall portions20a,20bare higher than the upper edges of the short sides22c,22dof the frame portion22.

As best seen inFIG. 8, V-shaped grooves21a,21c,21b,21dare formed in the upper center of the wall portions20a,20band the short sides22c,22d, respectively. As will be described later, the V-shaped grooves21a,21c,21b,21dfunction to engage with corresponding ones of four fixing members30,40,50,60(to be described later) in order to position the nozzle guide20to a predetermined position on the upper surface of a work bench (not shown). The V-shaped grooves21a,21c,21b,21dare formed in the center of the upper edges of the wall portions20a,20band the short sides22c,22dof the frame portion22. Said differently, the V-shaped grooves21a,21c,21b,21dare formed in the edges of the nozzle guide20that are adjacent to the nozzle rows14a,14bafter the actuator16is inserted into the nozzle guide20. Described in more detail, the V-shaped groove21ais formed in the wall portion20a, the V-shaped groove21cis formed in the wall portion20b, the V-shaped groove21bis formed in the short side22c, and the V-shaped groove21dis formed in the short side22d. As can be seen inFIGS. 7,10,11, and12, each of the V-shaped grooves21a,21c,21b,21dhas a V shape formed from two slanted side walls sandwiching a lower-most portion of the groove. The slanted sidewalls serve as guide portions for guiding the lower-most portion of a corresponding one of the fixing members30,40,50,60.

As shown inFIG. 8, the protrusion portions25a,25b,25c,25dare formed one at each corner of the frame portion22. As can be seen inFIGS. 7 and 10, the protrusion portions25a,25b,25c,25dprotrude upward from the same side of the four corners of the frame portion22as the wall portions20a,20bto substantially the same height as the wall portions20a,20b. Described in more detail, the protrusion portion25ais disposed with an upright posture at the corner between the wall portion20aand the short side22d, the protrusion portion25bis disposed with an upright posture at the corner between the wall portion20aand the short side22c, the protrusion portion25cis disposed with an upright posture at the corner between the wall portion20band the short side22c, and the protrusion portion25dis disposed with an upright posture at the corner between the wall portion20band the short side22d.

Notches24a,24b,24c,24dare defined in between the wall portions20a,20band the protrusion portions25a,25b,25c,25d. The notches24a,24b,24c,24deach have a substantial angled C shape with the upper portion open as viewed inFIGS. 7 and 10. As can be seen inFIG. 8, one of the notches24a,24b,24c,24dis formed near either lengthwise end of each of the long sides22a,22bat positions in between the protrusion portions25a,25b,25c,25dand the wall portions20a,20b. Described in more detail, the notch24ais formed between the wall portion20aand the protrusion portion25a, the notch24bis formed between the wall portion20aand the protrusion portion25b, the notch24cis formed between the wall portion20band the protrusion portion25c, and the notch24dis formed between the wall portion20band the protrusion portion25d.

Notch pairs24a,24band24c,24dare adjacent to each other with respect to the lengthwise direction of the frame portion22, that is, the left and right direction as shown inFIG. 8. The lengthwise-direction adjacent notch pairs24a,24band24c,24dare formed so that the distance between the inside edges, that is, the edges defined by the wall portions20a,20b, is shorter than the width of the wiring substrates17a,17b, but so that the distance between outside edges, that is, the edges defined by the protrusion portions25a,25b,25c,25d, is longer than the width of the wiring substrates17a,17b. Said differently, and as can be seen inFIG. 2, the wiring substrates17a,17bare each formed with a width in the left-right direction that is greater than the distance between the inside edges, but shorter than the distance between outside edges, of lengthwise-direction adjacent notch pairs24a,24band24c,24d. As a result, the left and right edges of the connection portion where the actuator substrates13a,13band the wiring substrates17a,17bconnect to each other will confront the notches24a,24b,24c,24das the nozzle guide20is being attached to the actuator16. Further, the outer left and right edges of the wall portions20a,20bthat define one inner side of the notches24a,24b,24c,24dtaper inward so that the notches24a,24b,24c,24dbroaden with proximity to the upper edge of the wall portions20a,20b.

With this configuration, the nozzle guide20will not contact the wiring substrates17a,17bwhile the nozzle guide20is being attached to the actuator16, so that the wiring substrates17a,17bwill not be snagged and peeled away from the actuator16by the nozzle guide20. Further, because this is accomplished by notches in the nozzle guide20, there is no need to create nozzle guide with a new shape. Instead, notches can merely be provided in a conventional nozzle cover so that the nozzle cover is easy to form. Because the edges of the notches have a tapering shape, there is little fear of damaging the wiring substrates even if the wiring substrates are erroneously contacted by the edge of the notch.

Next, the method of attaching the actuator16and the nozzle guide20together will be explained while referring toFIGS. 13 to 20. Before attempting to attach the actuator16and the nozzle guide20together, there is a need to position the nozzle guide20in a predetermined position.FIGS. 13 to 17show the method of positioning the nozzle guide20on a work surface, such as a work bench

The fixing members30,40,50,60for positioning the nozzle guide20in a predetermined position are provided on a flat surface of a work bench (not shown). As shown inFIG. 14, the fixing members30,40,.50,60are disposed a little to the outside from the outer periphery of the frame portion22of the nozzle guide20to be positioned, each at a position in confrontation with a corresponding one of the V-shaped grooves21a,21c,21b,21d, which are formed in the substantial centers of the edges of the nozzle guide20. The fixing members30,40,50,60include engagement portions31,41,51,61, respectively, pivot shafts32,42,52,62, respectively, and also bearings (not shown). More specifically, the fixing member30includes the engagement portion31and the pivot shaft32, the fixing member40includes the engagement portion41and the pivot shaft42, the fixing member50includes the engagement portion51and the pivot shaft52, and the fixing member60includes the engagement portion61and the pivot shaft62. The engagement portions31,41,51,61are made from metal columnar rods. The pivot shafts32,42,52,62each support one end of a corresponding one of the engagement portions31,41,51,61to enable the corresponding engagement portions31,41,51,61to pivot up and down.

As shown inFIG. 14, the nozzle guide20is positioned between the fixing members30,40,50,60, oriented with the wall portions20a,20bupward. Then, the engagement portions31,41,51,61are pivoted from the positions indicated by solid line inFIGS. 13 to 17downward, that is, toward the V-shaped grooves21a,21c,21b,21dof the nozzle guide20so that the engagement portions31,41,51,61engage in the V-shaped grooves21a,21c,21b,21das indicated by broken lineFIGS. 13 to 17. The positions of the fixing members30,40,50,60and the length of the engagement portions31,41,51,61are set so that the engagement portions31,41,51,61do not protrude out from the V-shaped grooves21a,21c,21b,21dinto the opening26of the frame portion22. After the engagement portions31,41,51,61engage in the V-shaped grooves21a,21c,21b,21d, the engagement portions31,41,51,61are further pivoted downward so that the engagement portions31,41,51,61press against the slanted walls of the V-shaped grooves21a,21c,21b,21d. At this time, the nozzle guide20moves, or adjusts its position, in response to the pressure against the slanted walls of the V-shaped grooves21a,21c,21b,21d. The engagement portions31,41,51,61press against the slanted walls of the V-shaped grooves21a,21c,21b,21duntil the engagement portions31,41,51,61engage the lower portion of the V-shaped grooves21a,21c,21b,21d, whereupon the position of the nozzle guide20is fixed in place with the nozzle guide20pressed against the flat surface of the work bench.

After the nozzle guide20is pressed against the flat surface of the work bench and fixed in place at the predetermined position, then as shown inFIGS. 18 to 20the actuator16is inserted into the opening26of the nozzle guide20from above, that is, from the side of the nozzle guide20formed with the V-shaped grooves21a,21c,21b,21d. It should be noted that the actuator16can be inserted into the nozzle guide20either manually or using a vertical-position positioning unit. The vertical-position positioning unit includes a fixing member to which the actuator16can be fixed and also a mechanism for moving the fixing member, and consequently the actuator16, toward or away from the nozzle guide20, to enable vertically positioning the actuator16with respect to the nozzle guide20.

Once the actuator16is inserted into the nozzle guide20, then as shown inFIG. 21, an actuator-positioning unit100including pressing members101,102,103, and104then adjusts the position of the actuator16in the X and Y directions (left-right and front-rear directions), so that the actuator16is accurately positioned at a predetermined position in the nozzle guide20. Once the position of the actuator16is set properly, the actuator16is pressed into the nozzle guide20using a tool (not shown). Then, the optically-cured adhesive19bis coated on and around the portion of the actuator16that is in the gap between the protrusion portions25a,25b,25c,25dof the nozzle guide20and the manifolds18, in order to temporarily fix the nozzle guide20to the actuator16during assembly. Also at this time, seal agent19ais coated between the actuator substrates13a,13band the wiring substrates17a,17b, between the nozzle guide20and the area nearby that portion of the wiring substrates17a,17b, and between short sides22c,22dof the nozzle guide20and the actuator16.

After the nozzle guide20and the actuator16are connected together and temporarily fixed together by the optically-cured adhesive19b, the engagement portions31,41,51,61are removed from the V-shaped grooves21a,21c,21b,21d. Then the ink recording head11is removed from the work bench and, as shown inFIGS. 2,4, and6, the seal agent19ais coated on the actuator16at the gaps in between the nozzle guide20and the nozzle plate15and the gaps between the wall portions20a,20bof the nozzle guide20and the manifolds18. As a result, the seal agent19awill be coated continuously around the outer periphery of the actuator16, with the exception of the upper and lower portions, so that it will be impossible for ink vapor to contact the actuator16. The actuator16is covered by the manifolds16, the nozzle guide20, the seal agent19a, and the optically-cured adhesive19b, thereby completing a single head unit.

The actuator16of the completed head unit is in a completely sealed condition, with the exception of the nozzle plate15, before the completed head unit is fixed onto the carriage through a base plate in the conventional manner. Therefore, the completed head unit can be filled with ink and tested for nozzle clogs and the like before the completed-head unit is fixed onto the carriage. Even if ink is ejected through the nozzles, the ink will not contact the actuator16. Also, although the nozzle guide20confronts the widthwise ends of the connection portion between the wiring substrates17a,17band the actuator16, the nozzle guide20does not contact the widthwise ends of the wiring substrates17a,17bbecause the notches24a,24b,24c,24dare located there. The widthwise ends of the connection portion between the wiring substrates17a,17band the actuator16can be considered to define the outer extent of the connection range between the wiring substrates17a,17band the actuator16. As an example,FIG. 6shows how the location of the notch24dprevents physical contact between the nozzle guide20and the leftmost end of the wiring substrate17b. With this configuration, the nozzle guide20will not snag and peel the wiring substrates17a,17boff while the nozzle guide20is being attached to the actuator16.

As described above, the V-shaped grooves21a,21c,21b,21dare formed in the upper edge of the frame-shaped nozzle guide20, which is opposite to the lower edge near the nozzle rows14a,14b. The engagement portions31,41,51,61are abutted against the V-shaped grooves21a,21c,21b,21dto press the front edge of the nozzle guide20against the flat surface of a work bench. The slanted surface of the V-shaped grooves21a,21c,21b,21dguides the nozzle guide20to a predetermined position. Then the actuator16is inserted into the nozzle guide20. Because the ink recording head11is manufactured in this manner, the nozzle guide20can be accurately positioned and the actuator16can be easily attached to the nozzle guide20. Also, the positioning operation of the nozzle guide20is easier to perform than other configurations because the V-shaped grooves21a,21c,21b,21dare formed on the upper edges of the nozzle guide20, which are opposite from the nozzle-side of the nozzle guide20. Also, the nozzle guide20can be easily guided to the predetermined position using only the simple configuration of the V-shaped grooves21a,21c,21b,21d. Positioning can be accurately performed from for directions because the V-shaped grooves21a,21c,21b,21dare formed at the substantial center of each edge of the frame-shaped nozzle guide20. It should be noted that the slanted surface for guiding the nozzle guide20to a predetermined position could be provided to the engagement portions31,41,51,61, instead of the V-shaped grooves21a,21c,21b,21d.

While the invention has been described in detail with reference to specific embodiments thereof, it would be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention, the scope of which is defined by the attached claims.

For example, the embodiment described specific examples of positioning members, engaging portions, and guiding portions. However, these are not to be considered limitations to the present invention. Alternative structures can be used as long as component combinations engage properly. Also the number of components can be freely changed.

Described in more detail, although the embodiment describes the nozzle guide20as being formed with the notches24a,24b,24c,24dso that the widthwise ends of the connection portion between the wiring substrates17a,17band the actuator16do not contact the nozzle guide20, any configuration that enables this is suitable. For example, the nozzle guide can be formed with holes or bulging sections that prevent contact between the widthwise ends of the connection portion and the nozzle guide20. A nozzle guide modified in either of these ways will be more rigid than the nozzle guide20formed with the notches24a,24b,24c,24d.

Also, in the embodiment, the nozzle guide20is formed from a single frame-shaped member. with this configuration, the burden on the assembler is lessened while he or she takes great care to assemble the actuator and the nozzle guide without damaging the ends of the wiring substrates. However, the nozzle guide could be configured from a plurality of members. Although such a multi-component structure would be difficult in itself to assemble, the operation of inserting the actuator16into the nozzle guide20can be dispensed with. That is, the nozzle guide20can be mounted around the outside of the actuator16so that there is no process of moving both edges in the nozzle guide20. As a result, the nozzle guide20is less likely to damage the actuator16.

Further, the positioning member provided to the nozzle guide20need not be the V-shaped grooves21a,21c,21b,21d, but could be any shape that can engage with the engagement portions31,41,51,61, such as a curved or angled U-shaped groove. Alternatively, the nozzle guide20could be provided with a protruding member as a positioning member. The protruding member could be made detachable from the nozzle guide20. The positioning member need not be provided at the edge of the nozzle guide20, but could be located on a peripheral surface of the nozzle guide20instead.

The fixing members30,40,50,60could be replaced with a structure that pinches the positioning member in order to fix the nozzle guide20in place, or with a groove having the same configuration as the outer periphery of the nozzle guide20. Further, the engagement portions31,41,51,61need not be a cylindrical rod shape, but could be angled or other configuration instead.

Further, the structure of the nozzle guide20that cooperates with the fixing members30,40,50,60to guide the nozzle guide20to the predetermined position is not limited to the slanted portion of the V-shaped grooves21a,21c,21b,21d, but could be any other suitable structure as well.