Patent Publication Number: US-2002001021-A1

Title: Head chip and method of fabricating thereof

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] The present invention relates to a head chip mounted to an ink jet type recording apparatus applied to, for example, a printer or a facsimile and a method of fabricating thereof.  
       [0003] 2. Description of the Related Art  
       [0004] Conventionally, there has been known an ink jet type recording apparatus for recording character or image on a recorded medium by using a recording head for injecting ink from a plurality of nozzles. According to the ink jet type recording apparatus, the recording head opposed to the recorded medium is provided at a head holder and the head holder is mounted to a carriage and scanned in a direction orthogonal to a direction of transferring the recorded medium.  
       [0005]FIG. 13 shows a disassembled outline view of an example of such a recording head and FIG. 14A and FIG. 14B illustrate sectional views of essential portions thereof. FIG. 14A is a sectional view of the recording head taken along the longitudinal direction of side walls. FIG. 14B is a sectional view of the recording head taken along the thickness direction of side walls. As shown by FIG. 13 and FIG. 14A,14B, a plurality of grooves  102  are provided at a piezoelectric ceramic plate  101  in parallel with each other and the respective grooves  102  are separated by side walls  103 . One end portion in a longitudinal direction of the respective groove  102  is extended up to one end face of the piezoelectric ceramic plate  101  and other end portion thereof is not extended up to other end face thereof and a depth thereof is gradually shallowed. Further, electrodes  105  for applying a driving electric field are formed on surfaces of the two side walls  103  in the respective groove  102  on the side of an opening portion thereof over the longitudinal direction.  
       [0006] A cover plate  107  is bonded to the opening side of the groove  102  of the piezoelectric ceramic plate  101  via an adhering agent  109 . The cover plate  107  includes an ink chamber  111  constituting a recess portion communicating with the shallowed other end portions of the respective grooves  102  and an ink supply port  112  penetrated from a bottom portion of the ink chamber  111  in a direction opposed to the groove  102 .  
       [0007] Further, a nozzle plate  115  is bonded to an end face of a bonded member bonded with the piezoelectric ceramic plate  101  and the cover plate  107  where the grooves  102  are opened and there are formed nozzle openings  117  at positions of the nozzle plate  115  opposed to the respective grooves  102 .  
       [0008] Further, a wiring board  120  is fixedly attached to a face of the piezoelectric ceramic plate  101  on a side opposed to the nozzle plate  115  and on a side opposed to the cover plate  107 . At the wiring board  120 , there are formed wirings  122  connected to the respective electrodes  105  by bonding wires  121  and drive voltage can be applied to the electrodes  105  via the wirings  122 .  
       [0009] According to the recording head constituted in this way, when ink is filled from the ink supply port  112  into the respective grooves  102  and predetermined drive electric field is operated to the side walls  103  of a predetermined one of the grooves  102  via the electrodes  105 , the side walls  103  are deformed and volume of the predetermined groove  102  is changed, thereby, ink in the groove  102  is injected from the nozzle opening  117 .  
       [0010] For example, as shown by FIG. 15, when ink is injected from the nozzle opening  117  in correspondence with a groove  102   a , positive drive voltage is applied to electrodes  105   a  and  105   b  at inside of the groove  102   a  and electrodes  105   c  and  105   d  respectively opposed thereto are grounded. Thereby, a drive electric field in a direction directed to the groove  102   a  is operated to side walls  103   a  and  103   b  and when the drive electric field is orthogonal to a polarized direction of the piezoelectric ceramic plate  101 , by the piezoelectric thickness slip effect, the side walls  103   a  and  103   b  are deformed in directions toward the groove  102   a , the volume of the inside of the groove  102   a  is reduced, pressure is increased and ink is injected from the nozzle opening  117 .  
       [0011] However, according to a head chip of recent years, there are desired large size formation and wide width formation accompanied by an increase in a number of the grooves, when the grooves are formed in the piezoelectric ceramic plate, the grooves are formed by grinding the piezoelectric ceramic plate and accordingly, with an increase in the number of the grooves, loss of a piezoelectric ceramic material is increased. Therefore, there poses a problem that the yield is poor and fabrication cost is high.  
       [0012] Further, the grooves are formed by grinding the piezoelectric ceramic plate one by one by a diamond rotary cutter and therefore, there poses a problem that time is taken for grinding, a grinding machine is expensive and cost for depreciation is imposed.  
       [0013] Since the grooves are ground by the diamond rotary cutter, there poses a problem that when grinding is continued, corners of the cutter are rounded by wear, a change in the shape of the groove results, the width of the groove is narrowed and the working accuracy is deteriorated.  
       SUMMARY OF THE INVENTION  
       [0014] In view of such a situation, it is a problem of the invention to provide a head chip reducing the fabrication cost and promoting the working accuracy and a method of fabricating thereof.  
       [0015] According to a first aspect of the invention for resolving the above-described problem, there is provided a head chip characterized in a head chip in which partition walls comprising a piezoelectric ceramic are arranged at predetermined intervals between two upper and lower sheets of a first and a second board, chambers are partitioned among the respective partition walls and by applying drive voltage to electrodes provided at side faces of the partition walls, volumes in the chambers are changed and ink filled at insides thereof is injected from nozzle openings wherein the first and the second boards are formed by a dielectric material and the partition walls are provided by fixedly attaching piezoelectric ceramic chips at predetermined intervals to a surface of either of the first and the second boards.  
       [0016] According to a second aspect of the invention, there is provided the head chip according to the first aspect, characterized in that the dielectric material is glass.  
       [0017] According to a third aspect of the invention, there is provided the head chip according to the first or second aspect, characterized in that the piezoelectric ceramic chips are fixedly attached to either of the first and the second boards in a state of being arranged at the predetermined intervals via spacers.  
       [0018] According to a fourth aspect of the invention, there is provided the head chip according to the third aspect, characterized in that the piezoelectric ceramic chips are fixedly attached to either of the first and the second boards and thereafter cut into a predetermined dimension in a longitudinal direction.  
       [0019] According to a fifth aspect of the invention, there is provided the head chip according to the third or fourth aspect, characterized in that the piezoelectric ceramic chips are fixedly attached to either of the first and the second boards and thereafter cut into a predetermined dimension in a thickness direction.  
       [0020] According to a sixth aspect of the invention, there is provided the head chip according to any one of the first through the fifth aspects, characterized in further comprising wirings conductive to the electrodes and extended up to outer sides of end portions of the partition walls in the longitudinal direction at the surface of either of the first and the second boards, wherein the wirings include an inorganic conductive film at a lowermost layer and a metal film formed thereon.  
       [0021] According to a seventh aspect of the invention, there is provided the head chip according to the sixth aspect, characterized in that the electrodes and the metal film are formed by selective electroless plating.  
       [0022] According to an eighth aspect of the invention, there is provided the head chip according to the fifth or the sixth aspect, characterized in that the inorganic conductive film is made of a material of at least one kind selected from a group consisting of ITO, SnO 2 , ZnO and ATO.  
       [0023] According to a ninth aspect of the invention, there is provided a method of fabricating a head chip characterized in a method of fabricating a head chip of arranging partition walls comprising piezoelectric ceramic chips at predetermined intervals between two upper and lower sheets of a first and a second substrate, the method comprising a step of fixedly attaching the piezoelectric ceramic chips arranged at the predetermined intervals to the first board via spacers, and a step of removing the spacers and fixedly attaching the second board thereto.  
       [0024] According to a tenth aspect of the invention, there is provided the method of fabricating a head chip according to the ninth aspect, characterized in further comprising a step of cutting the piezoelectric ceramic chips in a predetermined dimension in a longitudinal direction after fixedly attaching the piezoelectric ceramic chips thereto.  
       [0025] According to an eleventh aspect of the invention, there is provided the method of fabricating a head chip according to the ninth or the tenth aspect, characterized in further comprising a step of cutting the piezoelectric ceramic chips in a predetermined dimension in a thickness direction after fixedly attaching the piezoelectric ceramic chips thereto.  
       [0026] According to the invention, the partition walls comprising the piezoelectric ceramic chips are arranged at the predetermined intervals of the board and therefore, loss in working the piezoelectric ceramic material can be minimized. Further, the piezoelectric ceramic chips are preciously formed and therefore, working accuracy of the partition walls and the chambers can be promoted. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0027] In the accompanying drawings:  
     [0028]FIG. 1 is a perspective view of a head chip according to an embodiment of the invention;  
     [0029]FIG. 2 is a disassembled perspective view of the head chip according to the embodiment of the invention;  
     [0030]FIG. 3 illustrates a sectional view taken along a direction of providing chambers of the head chip according to the embodiment of the invention in parallel with each other and a sectional view taken along a line A-A′ thereof;  
     [0031]FIG. 4 illustrates top views showing a method of fabricating the head chip according to the embodiment of the invention:  
     [0032]FIG. 5 illustrates sectional views taken along the direction of providing the chambers in parallel with each other in correspondence with respective steps of FIG. 4;  
     [0033]FIG. 6 illustrates top views showing the method of fabricating the head chip according to the embodiment of the invention;  
     [0034]FIG. 7 illustrates sectional views taken along the direction of providing the chambers in parallel with each other in correspondence with respective steps of FIG. 6;  
     [0035]FIG. 8 is a perspective view showing assembling of a unit using the head chip according to the embodiment of the invention;  
     [0036]FIG. 9 illustrates perspective views showing assembling of the unit using the head chip according to the embodiment of the invention;  
     [0037]FIG. 10 illustrates perspective views showing a method of fabricating a head chip according to other embodiment of the invention;  
     [0038]FIG. 11 illustrates perspective views showing the method of fabricating the head chip according to the other embodiment of the invention;  
     [0039]FIG. 12 is a perspective view showing a mode of use of the unit using the head chip according to the embodiment of the invention;  
     [0040]FIG. 13 is a disassembled perspective view showing an outline of a recording head according to a conventional technology;  
     [0041]FIG. 14 illustrates sectional views showing the outline of the recording head according to the conventional technology; and  
     [0042]FIG. 15 is a sectional view showing the outline of the recording head according to the conventional technology. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0043] A detailed explanation will be given of the invention based on embodiments of the invention as follows.  
     Embodiment 1  
     [0044]FIG. 1 is a perspective view of a head chip according to Embodiment 1 of the invention, FIG. 2 is a perspective sectional view thereof and FIG. 3 illustrates a sectional view taken along a direction of providing chambers in parallel with each other and a sectional view taken along a line A-A′ thereof.  
     [0045] As illustrated, on top of a flow path board  11  formed by glass in a plate-like shape, there are provided a plurality of chambers  13  partitioned by partition walls  12  by providing a plurality of the partition walls  12  comprising piezoelectric ceramic at predetermined intervals in parallel with each other.  
     [0046] The partition walls  12  are fabricated by forming the piezoelectric ceramic in a predetermined shape and are fixedly attached onto the flow path board  11  via an adhering agent  26 .  
     [0047] Further, at a side face of the partition wall  12  constituting an inner face of the respective chamber  13 , there is formed an electrode  14  for applying a drive electric field respectively over an entire face thereof.  
     [0048] Further, above the flow path board  11 , there is extended a wiring  15  conducted to the respective electrode  14  up to an outer side in a longitudinal direction of the respective partition wall  13 .  
     [0049] The wiring  15  is constituted by an inorganic conductive film  15   a  provided at a lowermost layer and at least one layer of metal films provided above the inorganic conductive film  15   a  and according to the embodiment, the wiring  15  is constituted by the inorganic conductive film  15   a  and two layers of metal films  15   b  and  15   c.    
     [0050] In this case, the inorganic conductive film  15   a  is extended to only one end in the longitudinal direction along with the chamber  13  between the flow path board  11  and the partition wall  12 , and is firmly brought into contact with the electrodes  14  at end portions in a width direction of the extended inorganic conductive film  15   a , thereby, conduction between the electrode  14  and the wiring  15  is achieved.  
     [0051] Further, although according to the embodiment, the conduction between the wiring  15  and the electrode  14  is achieved by extending the inorganic conductive film  15   a  between the flow path board  11  and the partition wall  12 , the embodiment is not limited thereto so far as the conduction is achieved firmly, for example, the inorganic conductive film  15   a  may be provided to be brought into contact with an end face of the partition wall  12 , further, there may separately be provided a wiring for conducting the electrode  14  and the wiring  15 . At any rate, the electrode  14  and the wiring  15  may firmly be conducted.  
     [0052] Further, at a position opposed to one end in the longitudinal direction of the respective partition wall  12  above the flow path wall  11  and at the two side faces of the flow path board  11 , there are fixedly attached side walls  17  made of plastic by an adhering agent, there is partitioned an ink chamber  18  communicating with the respective chambers  13  by the guide walls  17  and the flow path board  11  above the glass board  11  and the ink chamber  18  is sealed by a cover plate  16  formed by glass in a plate-like shape bonded to sides of the partition walls  12  opposed to the flow path wall  11 . Further, at the cover plate  16 , there is formed an ink supply port  19  for supplying ink to the ink chamber  18  by, for example, sandblasting.  
     [0053] Further, a nozzle plate  20  is bonded to end faces of the partition walls  12  flushed with one end face of the flow path board  11  and at positions of the nozzle plate  20  opposed to the respective chambers  13 , there are respectively perforated nozzle openings  21 . The nozzle plate  20  may be formed by, for example, plastic, glass or polyimide film.  
     [0054] Here, a detailed explanation will be given of steps of fabricating a head chip according to the embodiment. Further, FIG. 4 and FIG. 6 are top views showing steps of fabricating a head chip and FIG. 5 and FIG. 7 are sectional views taken along a direction of providing the chambers  13  in parallel with each other in correspondence with respective steps of FIG. 4 and FIG. 6.  
     [0055] First, as shown by FIG. 4A and FIG. 5A, the inorganic conductive film  15   a  is formed in a predetermined shape above the flow path board  11  made of glass in the plate-like shape.  
     [0056] In details, after forming the inorganic conductive film  15   a  above the flow path board  11 , the inorganic conductive film  15   a  is formed, by patterning, on a rear side in a longitudinal direction where the chamber  13  is partitioned above the flow path board  11 , with a width more or less larger than the chamber  13  such that a portion of an end portion of the inorganic conductive film  15   a  is disposed between the flow path board  11  and the partition wall  12 .  
     [0057] In this case, as a material of the inorganic conductive film  15   a , there is pointed out ITO (oxide of indium and tin), SnO 2 , ZnO or ATO (oxide of antimony and tin) and according to the embodiment, ITO is used.  
     [0058] Further, a method of forming the inorganic conductive film  15   a  is not particularly limited, for example, the film can be formed by a sputtering method or a coating method and thereafter can be patterned by a photolithography method.  
     [0059] Successively, as shown by FIG. 4B and FIG. 5B, there are extended a plurality of guide wires  70  above the flow path board  11  as spacers for prescribing predetermined intervals among the partition walls. The guide wires  70  are used as positioning members when the partition walls  12  are fixed onto the flow path board  11  at later steps and therefore, the respective guide wires  70  are provided in parallel with each other at positions where the chambers  13  are partitioned at intervals more or less wider than the width of the partition wall  12 , in this case, at intervals wider than the width of the partition wall  12  by 1 through 2 μm.  
     [0060] Successively, as shown by FIG. 4C and FIG. 5C, the partition walls  12  are fixed onto the flow path board  11  via the adhering agent  26 . In details, the partition walls  12  previously coated with the adhering agent  26  at bottom faces thereof are arranged among the guide wires  70  above the flow path board  11  such that the end face of the flow path board  11  and the end faces of the partition walls  12  are flush with each other and the partition walls  12  are fixedly attached onto the flow path board  11  via the adhering agent  26 .  
     [0061] Further, the partition wall  12  is a piezoelectric ceramic chip formed by grinding piezoelectric ceramic in a predetermined shape and thereafter polishing thereof and the adhering agent  26  may not be coated at the bottom face of the partition wall  12  but may be coated in a predetermined shape previously to be arranged with the partition wall  12  above the flow path board  11  by screen printing.  
     [0062] Successively, as shown by FIG. 6A and FIG. 7A, a face of the partition wall  12  other than side faces thereof for partitioning the chambers  13 , is coated by a resist  25 . The step is for removing an extra electrode film at a step, mentioned later. Further, the resist  25  may naturally be provided before adhering the partition wall  12 .  
     [0063] Successively, as shown by FIG. 6B and FIG. 7B, at other than the surface of the flow path board  11 , that is, over entire faces of the partition walls  12  and the inorganic conductive films  15   a , there is adsorbed a start catalyst including palladium or platinum and thereafter, there are successively formed the metal film  15   b  of nickel and the metal film  15   c  of gold constituting the electrodes  14  and the wirings  15  by selective electroless plating.  
     [0064] By the selective electroless plating, on outer sides of the partition walls  12 , there are formed the wirings  15  comprising three layers of the inorganic conductive film  15   a , the metal film  15   b  of nickel and the metal film  15   c  of gold and over the entire faces of the partition walls  12 , there are formed the metal film  15   b  of nickel and the metal film  15   c  of gold. Further, the metal films  15   b  and  15   c  provided over the entire faces of the partition walls  12 , are conducted to the inorganic conductive films  15   a  provided between the partition walls  12  and the flow path substrate  11 .  
     [0065] Successively, as shown by FIG. 6C and FIG. 7C, by lifting off the resist  25  provided at the top faces of the partition walls  12  and two end faces in the longitudinal direction of the partition walls  12 , and unnecessary portions of the metal films  15   b  and  15   c  provided on the resist  25 , at the side faces of the respective partition walls  12 , there are formed the electrodes  14  comprising two layers of the metal film  15   b  of nickel and the metal film  15   c  of gold, which are not shortcircuited between two side faces of pairs of the partition walls  12 .  
     [0066] As described above, the electrodes  14  formed in this way, are conductive to the wirings via the inorganic conductive film  15   a  provided between the partition walls  12  and the flow path board  11 .  
     [0067] Thereafter, as shown by FIG. 1 through FIG. 3, the guide walls  17  made of plastic are fixedly attached to rear sides of the respective partition walls  12  and two end faces of the glass substrate  11  in the direction of providing the partition walls  12  in parallel with each other by the adhering agent to thereby partition the ink chamber  18  above the flow path board  11 . Further, the cover plate  16  is fixedly attached to sides of the partition walls  12  opposed to the glass board  11  by the adhering agent and the nozzle plate  20  perforated with the nozzle openings  21  in correspondence with the respective chambers  13 , is fixedly attached to the side end face of the flow path board  11  provided with the partition walls  12  by the adhering agent and the outer configuration is diced to thereby form the head chip  10 .  
     [0068] As has been explained, according to the embodiment, the partition walls  12  are provided above the flow path board  11  by fixedly attaching the piezoelectric ceramic chips previously formed in the predetermined shape onto the flow path board  11  by the adhering agent  26  and therefore, loss of the piezoelectric ceramic in forming the partition walls  12  can be minimized. Further, by using much of inexpensive glass at the flow path board  11  and the cover plate  16 , fabrication cost can be reduced.  
     [0069] Further, the piezoelectric ceramic chip is formed by previously forming the piezoelectric ceramic in the shape of the partition wall  12  and therefore, the working accuracy of the partition wall  12  can be promoted.  
     [0070] Further, the principle of driving the head chip  10  is as described in the conventional technology and therefore, an explanation thereof will be omitted.  
     [0071]FIG. 8 is a disassembled perspective view of a head chip unit mounted with the head chip  10  described above.  
     [0072] As shown by FIG. 8, above the flow path board  11  of the head chip  10 , there is mounted a drive circuit  31  comprising an integrated circuit for driving the head chip  10  by being directly connected to the wirings  15 . Further, the head chip  10  is integrated with a base plate  33  made of aluminum on the side of the flow path board  11  and a head cover  34  on the side of the cover plate  16 . The base plate  33  and the head cover  34  are fixed to each other by engaging engaging shafts  34   a  of the head cover  34  to engaging holes  33   a  of the base plate  33  and the head chip  10  is sandwiched by both members. The head cover  34  is provided with ink introducing paths  35  communicating with respectives of the ink supply ports  19  of the cover plate  16 .  
     [0073] Further, the head chip unit  40  is used, for example, by being integrated to a tank holder for attachably and detachably holding an ink cartridge.  
     [0074]FIG. 9A shows an example of such a tank holder. FIG.9B shows the tank holder  41  and the head chip unit  40  which is assembled with the tank holder  41 . The tank holder  41  shown in FIG. 9 is formed substantially in a box-like shape in which one face thereof is opened and is capable of attachably and detachably holding an ink cartridge, not illustrated. Further, at a top face of a bottom wall thereof, there are provided connecting portions  42  connected to the ink supply ports  19  constituting opening portions formed at a bottom portion of the ink cartridge. The connecting portions  42  are provided for respective inks of respective colors of, for example, black (B), yellow (Y), magenta (M) and cyan (C). At inside of the connecting portion  42 , there is formed an ink flow path, not illustrated, and a front end of the connecting portion  42  constituting the opening, there is provided a filter  43 . Further, the ink flow path formed in the connecting portion  42 , is formed to communicate up to a rear face side of the bottom wall and the respective ink flow path communicates with a head connecting port  46  opened at a partition wall of a flow path board  45  via an ink flow path, not illustrated, at inside of the flow path board  45  provided on the rear face side of the tank holder  41 . The head connecting port  46  is opened on a side of a side face of the tank holder  41  and at a bottom portion of the partition wall, there is provided a head chip unit holding portion  47  for holding the head chip unit  40 , mentioned above. At the head chip unit holding portion  47 , there are erected a surrounding wall  48  erected substantially in a channel-like shape surrounding the drive circuit  31  provided above the flow path board  11  and engaging shafts  49  disposed at inside of the surrounding wall  48  for engaging with engaging holes  40  a provided at the base plate  33  of the head chip unit  40 .  
     [0075] Therefore, a head unit  50  is completed by mounting the head chip unit  40  to the head chip unit holding portion  47 . At this occasion, the ink introducing paths  35  formed at the head cover  34  are connected to the head connecting ports  46  of the ink board  45 . Thereby, ink introduced from the ink cartridge via the connecting portion  42  of the tank holder  41 , is introduced into the ink introducing path  35  of the head chip unit  40  by passing through an ink flow path at inside of the ink board  45  and is filled in the ink chamber  18  and the chambers  13 .  
     Other Embodiment  
     [0076] Although an explanation has been given of the head chip according to the invention, the invention is not limited to Embodiment 1, described above.  
     [0077] For example, although according to Embodiment 1, the flow path board  11  is made of glass, the material of the flow path board  11  is not particularly limited so far as the material is a dielectric material.  
     [0078] Further, although according to Embodiment 1, portions of the wirings  15  and the electrodes  14  are constituted by the metal films  15   b  and  15   c  produced by the selective electroless plating, the invention is not limited thereto but, for example, with regard to the wirings, a wiring board previously formed with a wiring pattern may fixedly be attached onto the flow path board and with regard to the electrodes, a metal film may be formed by vapor deposition from a skewed direction which is publicly known.  
     [0079] Further, although according to the method of fabricating the head chip  10  of Embodiment 1, the guide wires  70  are provided in parallel with each other as spaces above the flow path board  11  and positioning in fixing the partition walls  12  onto the flow path board  11 , is carried out by the guide wires  70 , the invention is not limited thereto so far as the partition walls  12  can be arranged at the predetermined intervals above the flow path board  11 .  
     [0080] Here, there will be shown other examples of steps of fabricating a head chip.  
     [0081]FIG. 10 through FIG. 11 are perspective views showing other steps of fabricating a head chip.  
     [0082] First, similar to Embodiment 1, as shown by FIG. 4A and FIG. 5A, the inorganic conductive film  15   a  is formed by patterning in a predetermined shape above the flow path board  11 .  
     [0083] Successively, as shown by FIG. 10A, on a piezoelectric ceramic plate  81  constituting a material of the partition walls  12 , there are provided fixed wires  82  at predetermined intervals in parallel with each other as spacers for prescribing intervals between the partition walls to predetermined intervals and the piezoelectric ceramic plate  81  is further fixed onto the fixed wires  82  to thereby laminate a plurality of the piezoelectric ceramic plates  81  via the fixed wires  82 .  
     [0084] Successively, as shown by FIG. 10B, the piezoelectric ceramic plates  81  laminated via the fixed wires  82 , are cut to divide by a height of the partition wall  12  in a direction of providing the fixed wires  82  in parallel with each other to thereby form a piezoelectric ceramic plate assembly  80 .  
     [0085] Successively, as shown by FIG. 11A, the piezoelectric ceramic plate assembly  80  is fixedly attached onto the flow path board  11  with a cut face of the piezoelectric ceramic plate assembly  80  as an adhering face. At this occasion, the piezoelectric ceramic plate assembly  80  and the flow path board  11  are fixedly attached to each other such that one end face in a longitudinal direction of the piezoelectric ceramic plate  81  and an end face of the flow path board  11  are flush with each other and an adhering agent is coated only at portions of a bottom face of the piezoelectric ceramic plate assembly  80  for constituting the partition walls  12 .  
     [0086] Successively, as shown by FIG. 11B, one row of the fixed wires  82  of the piezoelectric ceramic plate assembly  80  above the flow path board  11  in a direction of laminating the fixed wires  82 , is eliminated by grinding. At this occasion, portions of the piezoelectric ceramic plates  81  are also ground, the adhering agent is not coated on the portions of the bottom face of the piezoelectric ceramic plate assembly  80  other than those of the partition walls  12  and therefore, only the partition walls  12  are fixedly attached onto the flow path board  11 .  
     [0087] Further, the length of the chamber  13  is the interval for providing the fixed wires  82  in parallel with each other and therefore, it is necessary to provide the fixed wires  82  in parallel with each other previously at pertinent intervals.  
     [0088] Thereafter, similar to the fabricating steps shown in FIG. 6 through FIG. 7 of Embodiment 1, mentioned above, the electrodes  14  and the wirings  15  are formed at the flow path board  11  provided with the partition walls  12 , the guide walls  16 , the cover plate  17  and the nozzle plate  20  are fixedly attached and the outer configuration is ground to thereby form the head chip  10 .  
     [0089] According to the fabricating steps, loss of the piezoelectric ceramic can be restrained and the head chip can be fabricated at lowcost. Further, shortening of a fabricating time period can be achieved.  
     [0090] Further, the above-described head unit  50  is used by, for example, being mounted to a carriage of an ink jet type recording apparatus. FIG. 12 shows an outline of an example of the mode of use.  
     [0091] As shown by FIG. 12, a carriage  61  is mounted over a pair of guide rails  62   a  and  62   b  movably in the axial direction and is carried via a timing belt  65  hung over a pulley  64   a  connected to a carriage drive motor  63  provided at ends of the guide rails  62  on one side and a pulley  64   b  provided at ends thereof on other side. There are provided respective pairs of carry rollers  66  and  67  along the guide rails  62   a  and  62   b  on both sides of the carriage  61  in a direction orthogonal to a direction of carrying the carriage  61 . The carry rollers  66  and  67  carry a recorded medium S on a lower side of the carriage  61  in the direction orthogonal to the direction of carrying the carriage  61 .  
     [0092] The above-described head unit  50  is mounted above the carriage  61  and the above-described ink cartridge can be attached attachably and detachably to the head unit  50 .  
     [0093] According to the ink jet type recording apparatus, character and image can be recorded on the recorded medium S by the head chip by scanning the carriage  61  in the direction orthogonal to a direction of feeding the recorded medium S while feeding thereof.  
     [0094] As has been explained above, according to the invention, the upper and lower boards are formed by a dielectric material, the piezoelectric ceramic chips previously formed in the predetermined shape, are fixedly attached onto the board via the spacers to thereby form the partition walls and accordingly, loss of the piezoelectric ceramic in forming the partition walls can be minimized, the fabrication cost can be reduced and the fabrication time period can be shortened. Further, the chambers are not formed by grinding but the partition walls and the chambers are partitioned by providing the piezoelectric ceramic chips on the board via the spacers and therefore, accuracy of the partition wall and the chamber can be promoted.