JP3692889B2 - Piezoelectric vibrator unit, ink jet recording head using the same, and method of manufacturing piezoelectric vibrator unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a piezoelectric vibrator unit suitable for ejecting ink droplets, an ink jet recording head using the same, and a method of manufacturing the piezoelectric vibrator unit, and more particularly to an improved piezoelectric vibrator positioning structure.
[0002]
[Prior art]
In this type of ink jet recording head (hereinafter referred to as recording head), for example, a flow path unit having a pressure chamber, a reservoir, and the like, and a back surface side of the flow path unit are arranged to change the volume of the pressure chamber. Some include a piezoelectric vibrator unit having a plurality of vibrators, and a case in which an accommodation space capable of housing the piezoelectric vibrator unit is formed, and a flow path unit is joined to the tip.
[0003]
This piezoelectric vibrator unit is manufactured by the following procedure, for example. First, common internal electrodes and individual internal electrodes are alternately stacked with a piezoelectric material interposed therebetween to create a plate-shaped laminate, and the common external electrode connected to the common internal electrode and the individual external electrode connected to the individual internal electrode An electrode is formed on the surface of the laminate. And after baking this laminated body, the base end side part is joined on a fixed board, and the front end side part of a laminated body is cut | disconnected by the very thin width | variety of about 50 micrometers-100 micrometers with a wire saw, a dicing saw, etc. A group of vibrators is formed.
The vibrators located at both ends in the vibrator arrangement direction in this vibrator group function as dummy vibrators. This dummy vibrator is not involved in ink droplet ejection, and is used, for example, to define the position of the piezoelectric vibrator unit in the case.
[0004]
[Problems to be solved by the invention]
By the way, joining of a case and a flow path unit is performed with an adhesive agent. At the time of bonding, if the applied adhesive is excessive, the excessive adhesive may flow out from the overlapping surface of the case and the flow path unit to the housing empty part side. Due to the agent, the attachment position of the piezoelectric vibrator unit in the case may be shifted from the normal position. For example, when the outflowing adhesive is solidified and the solidified adhesive is interposed between the tip surface portion of the dummy vibrator and the flow path unit, the piezoelectric vibrator unit is equal to the thickness of the adhesive. Is shifted to the rear side (that is, the direction away from the flow path unit).
If the mounting position of the piezoelectric vibrator unit is shifted to the rear side, the drive vibrator disposed between the dummy vibrators is allowed between the tip surface portion of the drive vibrator and the island portion of the flow path unit. A gap with a size exceeding the range is generated, which causes manufacturing defects.
[0005]
In addition, a molded product made of synthetic resin is preferably used in the above case, but due to the convenience of the mold, the mating surface (parting line) of the upper mold and the lower mold is the fixed surface of the flow path unit in the case It tends to be the same position as. In this parting line, burrs are likely to occur during molding. Depending on the shape of the burrs, when the piezoelectric vibrator unit is inserted into the case, the burrs are sandwiched between the tip surface portion of the dummy vibrator and the flow path unit. As a result, the mounting position of the piezoelectric vibrator unit is shifted to the rear side by the thickness of the burr, resulting in manufacturing failure.
[0006]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and prevent a manufacturing defect caused by a positional deviation of the piezoelectric vibrator unit, an ink jet recording head using the same, and a piezoelectric vibrator. It is to provide a method for manufacturing a unit.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is configured as follows.
The invention according to claim 1 is a piezoelectric vibrator unit including a piezoelectric vibrator group in which a plurality of piezoelectric vibrators are arranged,
Piezoelectric vibrations characterized in that the vibrator at the end in the row direction is configured as a dummy vibrator for positioning the vibrator, and the corner portion outside the row in the row direction at the tip of the dummy vibrator is removed by chamfering. It is a child unit.
[0009]
The invention according to claim 2 is the piezoelectric vibrator unit according to claim 1, wherein the piezoelectric vibrator group is a comb-like vibrator group divided into comb teeth.
[0010]
According to a third aspect of the present invention, the dummy vibrator includes a dummy vibrator main body and a dummy vibrator forming member attached outside the dummy vibrator main body in the row direction. The piezoelectric vibrator unit according to claim 1 or 2, wherein the forming member is made of a material having higher toughness than a constituent material of the piezoelectric vibrator.
[0011]
The invention according to claim 4 is the piezoelectric vibrator unit according to claim 3, wherein a tip portion of the dummy vibrator forming member is chamfered.
[0012]
According to a fifth aspect of the present invention, the dummy vibrator includes a main dummy vibrator and an auxiliary dummy vibrator provided outside the main dummy vibrator in the row direction, and the auxiliary dummy vibrator is 3. The piezoelectric vibration according to claim 1, wherein chamfering is performed together with the main dummy vibrator, and the outer surface of the main dummy vibrator on the tip side of the auxiliary dummy vibrator is used as a positioning surface. 4. It is a child unit.
[0013]
According to a sixth aspect of the present invention, the piezoelectric vibrator unit according to any one of the first to fifth aspects of the present invention and an elastic plate that constitutes a part of the pressure chamber sealing material that communicates with the nozzle opening. A flow path unit and a housing that can accommodate a piezoelectric vibrator unit therein, and a case in which the flow path unit is joined to the tip.
The ink jet recording head is characterized in that positioning is performed by bringing the outer surface of the dummy vibrator into contact with the wall surface of the housing space, and the piezoelectric vibrator unit is attached to the case.
[0014]
According to a seventh aspect of the present invention, there is provided the ink jet recording according to the sixth aspect, wherein an inclined guide portion that guides the dummy vibrator is formed on a wall surface of the accommodating space where the dummy vibrator contacts. Head.
[0015]
The invention according to claim 8 is characterized in that a positioning step portion that comes into contact with the outer surface of the dummy vibrator is protruded on the wall surface of the accommodating space where the dummy vibrator comes into contact. Inkjet recording head.
[0016]
The invention according to claim 9 is a laminate creation step of creating a plate-like laminate by sandwiching a piezoelectric body between electrodes,
A chamfering step of chamfering both corners on the side to be a free end in the laminate;
A firing step of firing the chamfered laminate,
Piezoelectric vibrations characterized in that a sintered vibrator is cut to create a drive vibrator and a vibrator creation process for creating a dummy vibrator for vibrator positioning at the end of the vibrator arrangement direction. It is a manufacturing method of a child unit.
[0017]
The invention according to claim 10 is a laminate creation step of creating a plate-like laminate by sandwiching a piezoelectric body between electrodes,
A firing step of firing the laminate;
Chamfer both corners on the side that will be the free end of the fired laminate, and cut this laminate to create a drive vibrator. At the end of the vibrator array, dummy vibration for positioning the vibrator A method of manufacturing a piezoelectric vibrator unit, wherein a vibrator creating process for creating a child is sequentially performed.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments. FIG. 1 is an enlarged cross-sectional view showing a main part of an ink jet recording head 1 to which the first embodiment of the present invention is applied, and FIG. 2 is a view taken along the line AA.
[0019]
The recording head 1 includes a case 2, a flow path unit 3, a piezoelectric vibrator unit 4, and the like. In the description of the recording head 1, for the sake of convenience, the upper side in FIG. 1 is referred to as the front end side (front side), and the lower side in FIG. 1 is referred to as the base end side (rear side).
[0020]
The case 2 is a block-shaped member made of a synthetic resin in which both the front end and the rear end are open, and the opening shape is an elongated rectangular housing cavity 5 provided in the nozzle row direction, that is, the vibrator row arrangement direction (described later). is there. The flow path unit 3 is bonded to the front end of the case 2 by bonding, and the piezoelectric element is placed in the accommodation space 5 with the front end surface portion of the transducer group 21 facing the front end opening of the accommodation space 5. The vibrator unit 4 is accommodated and fixed. An ink supply pipe 6 communicating with the ink cartridge is provided at the base end side at the side of the housing space 5. Further, as shown in FIG. 2, the dummy vibrator 28 of the piezoelectric vibrator unit 4 is provided on the front end side portion of the wall surface 5a on the short side of the opening, which is the wall surface of the housing space 5 (inner wall surface of the case 2). An inclined guide portion 43 for guiding is provided. The inclined guide part 43 will be described later.
[0021]
The flow path unit 3 includes a flow path forming plate 7, a nozzle plate 8, and an elastic plate (pressure plate) 9.
[0022]
The nozzle plate 8 is a thin plate-like member in which a large number (for example, 96) of nozzle openings 10 are opened in a row at a pitch corresponding to the dot formation density, and is constituted by, for example, a stainless steel plate. The flow path forming plate 7 stacked on the nozzle plate 8 includes a reservoir 11 into which ink supplied through the ink supply pipe 6 flows, and a pressure chamber for generating ink pressure necessary to eject ink from the nozzle opening 10. 12, an ink supply port 13 and the like for communicating the reservoir 11 and the pressure chamber 12 are formed. And in this embodiment, these each part is formed by etching a silicon wafer.
[0023]
In this embodiment, the elastic plate 9 has a double structure in which a polymer film such as PPS (polyphenylene sulfite) is laminated on the stainless steel plate 15 as the elastic film 14. The stainless steel plate 15 is formed by removing unnecessary portions such as a portion corresponding to the reservoir 11 by etching to form an island portion 16 (thick portion), and an elastic film 14 (thin portion) around the island portion 16. Only the elastic portion 17 is formed. This island portion 16 has a block shape in which a contact surface with which a driving vibrator 29 (described later) is in contact is provided on the back side, and a large number of island portions 16 are provided at a pitch corresponding to the dot formation density, like the nozzle openings 10.
[0024]
The nozzle plate 8 is disposed on the front surface side of the flow path forming plate 7 and the elastic plate 9 is disposed on the rear surface side. The flow path forming plate 7 is sandwiched between the nozzle plate 8 and the elastic plate 9 and is integrated by bonding or the like. As a result, the flow path unit 3 is formed. In the flow path unit 3, the elastic plate 9 constitutes part of a sealing material that seals the pressure chamber 12 and the ceiling surface of the reservoir 11.
[0025]
The piezoelectric vibrator unit 4 is roughly constituted by a vibrator group 21 and a fixed plate 22. As shown in FIG. 2, the vibrator group 21 is arranged in a comb-teeth shape by joining the base end portion to the fixed plate 22, and is arranged at both ends in the vibrator arrangement direction (plane direction). The dummy vibrators 28 and 28 are located, and a large number of drive vibrators 29 are arranged between the dummy vibrators 28 and 28. Here, the drive vibrator 29 is a piezoelectric vibrator involved in the ejection of ink droplets, and is divided into needles having an extremely narrow width of about 50 μm to 100 μm, for example. The dummy vibrators 28 and 28 are piezoelectric vibrators that do not participate in the ejection of ink droplets, and are formed to define the position of the piezoelectric vibrator unit 4 in the case 2. The piezoelectric vibrators 28 and 29 in the present embodiment are so-called longitudinal vibration mode piezoelectric vibrators.
[0026]
Next, the drive vibrator 29 will be described. As shown in FIG. 3, the drive vibrator 29 is formed by alternately stacking common internal electrodes 32 and individual internal electrodes 33 with the piezoelectric bodies 31 interposed therebetween. Here, the common internal electrode 32 is an electrode set to the same potential level for all the drive vibrators 29, and the individual internal electrode 33 is an electrode for which the potential level is set for each drive vibrator 29. A portion of the drive vibrator 29 from the tip of the vibrator to about half or about two-thirds of the longitudinal direction of the vibrator (direction orthogonal to the stacking direction) is defined as the free end 23a, and the remaining portion is the base end. This is part 23b. A fixing plate 22 is joined to the base end portion 23b. In short, the drive vibrator 29 is fixed to the fixing plate 22 in a so-called cantilever state.
[0027]
An active region L (overlap portion) in which the common internal electrode 32 and the individual internal electrode 33 overlap is formed in the free end portion 23a. When a potential difference is applied to these internal electrodes 32 and 33, the piezoelectric body 31 in the active region L is deformed (actuated), and the free end portion 23a is displaced in the longitudinal direction of the vibrator to expand and contract. The base end of the common internal electrode 32 is electrically connected to the common external electrode 37 at the base end face portion of the drive vibrator 29, and the tip of the individual internal electrode 33 is connected to the individual external electrode 36 at the tip face portion 29 a of the drive vibrator 29. Conducted. Here, the individual external electrode 36 is an electrode that conducts the flexible cable 24 and each individual internal electrode 33, and the common external electrode 37 is an electrode that conducts between the flexible cable 24 and the common internal electrode 32.
[0028]
The flexible cable 24 is disposed on the wiring connection surface side of the base end portion 23b, and is electrically connected to the individual external electrode 36 and the common external electrode 37 on the base end portion 23b. A driving pulse is supplied to each of the electrodes 32, 33, 36, and 37 through the flexible cable 24.
[0029]
As shown in FIGS. 1 and 2, in the mounted state of the piezoelectric vibrator unit 4, the front end surface portion 29 a of the drive vibrator 29 is in contact with the island portion 16 of the elastic plate 9 from the back side. 29a and the island part 16 are adhere | attached with the adhesive agent. When the drive pulse is supplied to the drive vibrator 29, the drive vibrator 29 expands and contracts in the longitudinal direction of the vibrator and deforms the elastic film 14 constituting the elastic portion 17 in the front-rear direction. As the elastic part 17 moves in the front-rear direction, the pressure chamber 12 expands or contracts to change its volume. When ink droplets are ejected from the nozzle openings 10, a drive signal is selectively applied to the drive vibrator 29 that ejects ink droplets. For example, the pressure chamber 12 is once expanded and then contracted. In this way, the ink in the reservoir 11 flows into the pressure chamber 12 as the pressure chamber 12 expands, and the pressure of the ink in the pressure chamber 12 increases as the pressure chamber 12 contracts. Then, the ink pushed out from the nozzle opening 10 is ejected as ink droplets.
[0030]
Next, the dummy vibrator 28 will be described. In this embodiment, the dummy vibrator 28 is formed at both ends in the vibrator arrangement direction when the laminated body 41 (see FIG. 8) is divided into a plurality of drive vibrators 29 by using a wire saw, a dicing saw, or the like. It is formed. The outer surface 28c in the row direction of the dummy vibrators 28 is also cut by a wire saw, a dicing saw, or the like when the teeth are formed, and the outer surface 28c is positioned for positioning in the vibrator row direction. It becomes a positioning surface. Further, the front end surface portion 28d of the dummy vibrator 28 serves as a second positioning surface for positioning in the front-rear direction.
As described above, when the outer surface 28c of the dummy vibrator 28 is used as a positioning surface, an alignment surface can be formed by the same process as that for dividing the laminated body 41 into the vibrators 28 and 29, so that the accuracy is very high. Can be obtained.
[0031]
The dummy vibrator 28 is also composed of a free end portion 28a protruding from the edge of the fixed plate 22 and a base end portion 28b joined to the fixed plate 22, and in a state like a so-called cantilever. It is fixed to the fixed plate 22. The free end portion 28a and the base end portion 28b of the dummy vibrator 28 are configured not to expand and contract.
[0032]
A chamfered portion 42 is formed at the tip of these dummy vibrators 28, 28. The chamfered portion 42 is formed by obliquely removing the corners on the outer side in the row direction at the tip portions of the dummy vibrators 28 and 28 by chamfering or the like. The shape of the removed portion is not limited to this embodiment. For example, it may be removed in an arc shape or in an L shape.
[0033]
The reason why the chamfered portion 42 is provided is that an empty portion formed by the chamfered portion 42 is used as an escape region S for adhesive or burr. That is, when the piezoelectric vibrator unit 4 is mounted on the case 2 to which the flow path unit 3 is attached, the outer surface 28 c of the dummy vibrator 28 is brought into contact with the inclined guide portion 43 of the case 2. The front end surface portion 28 d of this is in contact with the stainless steel plate 15 of the flow path unit 3. In this contact state, by providing the chamfered portion 42, a relief region S is formed on the outer side in the row direction at the tip portion of the dummy vibrator 28.
Then, the excess adhesive X flowing out from the overlapping surface of the case 2 and the flow path unit 3 can be stored in the escape region S. That is, the escape area S can be used as a buffer area for containing the adhesive X.
[0034]
As a result, defects caused by the presence of the solidified adhesive X between the tip surface portion 28d and the stainless steel plate 15, for example, the mounting position of the piezoelectric vibrator unit 4 is shifted to the rear side from the normal position. Adhesive failure between the tip surface portion 29a of the drive vibrator 29 and the island portion 16 can be reliably prevented. As a result, since the piezoelectric vibrator unit 4 can be attached to a regular position, the distal end surface portion 29a of the drive vibrator 29 and the island portion 16 can be securely bonded.
[0035]
Note that the inclination angle θ2 of the chamfered portion 42 can be appropriately set to an angle at which the necessary volume relief region S can be formed and the required rigidity of the dummy vibrator 28 can be ensured. For example, a range of 5 ° to 45 ° can be preferably used, and a range of 10 ° to 20 ° can be more preferably used.
[0036]
Further, even when the parting line 44 at the time of molding the case 2 is set to a position substantially coincident with the fixing surface of the case 2 and the flow path unit 3, burrs are generated at the opening edge portion of the housing empty portion 5. In the same manner as described above, burrs can be accommodated in the escape region S, and burrs can be prevented from being caught. As a result, the dummy vibrators 28 can be reliably brought into contact with the stainless steel plate 15. Therefore, the piezoelectric vibrator unit 4 can be fixed at a regular position, and adhesion failure of the drive vibrators 29 can be prevented.
[0037]
Next, the inclination guide part 43 will be described. The inclined guide portion 43 protrudes from the inner wall surface 5 a on the short opening side of the storage space 5 toward the facing short opening side. The inclined guide portion 43 includes an inclined guide surface 43a and a contact surface 43b. The contact surface 43 b is a surface with which the outer surface 28 c of the dummy vibrator 43 inserted into the storage space 5 contacts. The inclined guide surface 43a is an inclined surface for guiding the tip end portion of the dummy vibrator 28 to the contact surface 43b, and is formed so as to be directed toward the short side of the opening opposite to the tip end side of the case 2. ing.
[0038]
And when accommodating the piezoelectric vibrator unit 4 in the accommodation empty part 5, it inserts from the back side opening of the accommodation empty part 5 in the state which made the front-end | tip of the vibrator group 21 the head. At this time, the dummy vibrator 28 is inserted in a state where the outer surface 28c side is brought close to the inner wall surface 5a side.
Here, the inclination angle θ1 of the inclined guide surface 43a is preferably set to the same angle as the inclination angle θ2 of the chamfered portion 42 or smaller than the inclination angle θ2. With this setting, the chamfered portion 42 and the inclined guide surface 43a of the dummy vibrator 28 abut on the surface, or the top formed by the chamfered portion 42 and the tip surface portion 28d abuts on the inclined guide surface 43a. Therefore, the impact on the dummy vibrator 28 due to the insertion can be mitigated.
When the piezoelectric vibrator unit 4 is pushed into the flow path unit 3 from this contact state, the tops of the tip surface portion 28d and the chamfered portion 42 move along the inclined guide surface 43a. As a result, the piezoelectric vibrator unit 4 is smoothly inserted into the housing space 5.
[0039]
In this manner, the outer corners in the surface direction of the tip portions of the dummy vibrators 28 and 28 are cut off obliquely to form the chamfered portion 42, and the inclined guide portion 43 that guides the dummy vibrator 28 is provided. The insertability of the piezoelectric vibrator unit 4 into the empty part 5 can be improved, and the breakage of the dummy vibrators 28 and 28 can be effectively prevented.
[0040]
Next, a method for manufacturing the piezoelectric vibrator unit 4 will be described. In manufacturing the piezoelectric vibrator unit 4, first, a plate-like laminate 41 (see FIG. 8A) is created (laminate creation step). In this step, first, the common internal electrode 32 and the individual internal electrode 33 are overlapped at the distal end portion that becomes the free end portion 23a, and only the common internal electrode 32 is not covered at the proximal end portion that becomes the proximal end portion 23b. The plate-like laminate 41 is created by alternately laminating the common internal electrodes 32 and the individual internal electrodes 33 with the piezoelectric bodies 31 interposed therebetween so that the overlapping region is formed. That is, the laminated body 41 is formed by laminating the piezoelectric body 31 between the electrodes 32 and 33.
[0041]
When the plate-like laminate 41 is created, the individual external electrodes 36 are formed in series on the distal end surface portion of the laminate 41 and the range from the distal end to the base end portion 23b of the wiring connection surface, A common external electrode 37 is formed in series on the base end surface portion and the range from the base end to the base end portion 23b on the wiring connection surface and the fixed plate mounting surface to form a laminate 41 with external electrodes.
[0042]
In the present embodiment, a chamfering process is performed before firing the laminate 41. In this chamfering step, as shown in FIG. 8A, the side corners 91 and 91 on the free end side of the laminate 41 are chamfered. That is, in this chamfering process, the corner portions of the dummy vibrators 28 are cut off. As described above, when the laminate 41 before firing is chamfered, the laminate 41 before firing has toughness, so that the laminate 41 can be easily chamfered using, for example, a press device or a shearing device. This can be done and manufacturing man-hours can be minimized.
[0043]
Next, the laminated body 41 that has been chamfered is introduced into, for example, a firing furnace, and a firing process is performed in which the laminated body 41 is fired.
[0044]
After that, a vibrator creating step is performed in which a plate-shaped laminate is cut to create a plurality of vibrators. In this step, first, as shown in FIG. 8B, the fixing plate 22 is bonded to the fixing plate mounting surface of the base end portion 23b of the laminate by bonding or the like. When the fixed plate 22 is joined, a plate-like laminated body is divided using a wire saw, a dicing saw, or the like, and is cut into elongated needle-like piezoelectric vibrators 29... And dummy vibrators 28, 28. At this time, the vibrators 28 and 29 are cut so as to be completely cut on the fixed plate 22.
The reason why the plate-like laminate is fixed to the fixing plate 22 is that the teeth are split so that the teeth can be split stably and the subsequent handling is facilitated. Therefore, the laminated body after the tooth splitting may be fixed to the fixing plate 22 if the tooth splitting can be stably performed.
[0045]
In the above manufacturing method, the laminate is chamfered before the firing process, but the process proceeds to the firing process without performing the chamfering process. The corners on the side that becomes the free end of the laminated body 41 may be chamfered, and this laminated body may be joined to the fixing plate 22 and cut to create the drive vibrator 29 and the dummy vibrator 28. .
After performing the firing process in this manner, the dummy vibrators 28, 28 are performed without increasing the number of manufacturing processes by performing chamfering in the vibrator creating process for splitting the plate-like laminate into comb teeth. Can be chamfered.
[0046]
In addition, regarding the above chamfering process, a method of cutting a corner by punching with a press, and a method of cutting a corner by a wire saw or a dicing saw are exemplified. May be removed by polishing.
[0047]
Incidentally, the dummy vibrator 28 of the present invention is not limited to the above-described configuration. For example, the dummy vibrator 28 may be composed of a dummy vibrator main body and a dummy vibrator forming member attached outside the dummy vibrator main body in the row direction. Hereinafter, the second embodiment configured as above will be described.
[0048]
As shown in FIG. 4, in the present embodiment, the dummy vibrators separate from the piezoelectric vibrators are disposed outside the vibrator arrangement direction of the dummy vibrator bodies 70 and 70 located at both ends of the vibrator group 21. Forming members 71 and 71 are attached, and the dummy vibrator main body 70 and the dummy vibrator forming member 71 constitute the dummy vibrators 28 and 28. The dummy vibrator forming member 71 is fixed in a state in which the tip thereof is shifted to the rear side (fixed substrate 22 side) by a step D from the tip of the dummy vibrator body 70.
[0049]
The dummy vibrator forming member 71 is made of a material having higher toughness than ceramics, which is a constituent material of the piezoelectric vibrator, such as a metal material or a ceramic material. A chamfered portion 72 is formed at the tip of the dummy vibrator forming member 71. The chamfered portion 72 is formed by chamfering into a shape in which the corners on the outer side in the arrangement direction of the transducers at the front end portions of the dummy transducer forming members 71 and 71 are cut off obliquely. It is a part that exhibits the same effect. The chamfered shape is not limited to a straight shape as in the present embodiment, and may be a curved shape.
[0050]
As described above, the dummy vibrator forming member 71 separate from the piezoelectric vibrator 29 is attached to the outside of the dummy vibrator main body 70 in the vibrator row direction, and the dummy vibrator forming member 71 is attached to the piezoelectric vibrator. The bending strength of the dummy vibrator 28 is increased by using a material having higher toughness than the constituent material. In addition, since the chamfered portion 72 is formed at the tip portion of the dummy vibrator forming member 71, the insertion property of the piezoelectric vibrator unit 4 into the housing space 5 of the case 2 can be improved, and the dummy Damage to the vibrator 28 can be prevented more reliably.
[0051]
Further, since the dummy vibrator forming member 71 is attached so that the tip of the dummy vibrator forming member 71 is located behind the tip of the dummy vibrator main body 70 by the step D, the empty space generated by the step D is generated. The escape region S can be configured by the portion and the empty portion generated by the chamfered portion 72.
And this escape area S can prevent reliably the malfunction resulting from an excessive adhesive agent and the burr | flash of an opening edge part.
[0052]
As described above, when the dummy vibrator 28 is constituted by the dummy vibrator main body 70 and the dummy vibrator forming member 71, the dummy vibrator is provided on both sides of the laminated body 41 that is on the outer side in the vibrator arrangement direction. A member to be the forming member 71 is bonded in advance, and the vibrators 28 and 29 are chamfered by a comb-teething process to cut off corner portions.
[0053]
Next, the dummy vibrator 28 according to the third embodiment will be described. In this embodiment, the dummy vibrator 28 includes a main dummy vibrator and an auxiliary dummy vibrator provided on the outer side in the row direction from the main dummy vibrator, and the auxiliary dummy vibrator is the main dummy vibrator. And chamfered.
[0054]
As described above, the dummy vibrators 28 are located at both ends of the comb-like vibrator group 21 in the vibrator arrangement direction, and the laminated body 41 serving as a piezoelectric vibrator is divided into a plurality of vibrators 28 and 29. It is formed by forming. However, since the outermost surface in the direction in which the transducers are arranged is a contact surface with the inner wall surface (5a, 43b) of the case 2, it is cut with a wire saw or a dicing saw to form a flat surface. There is a need. For this reason, normally, when the vibrators 28 and 29 are divided, the vibrator located at the outermost part in the vibrator arrangement direction is removed as an extra vibrator by removing it, etc. The second vibrator is used as the dummy vibrator 28.
[0055]
In this embodiment, paying attention to this point, as shown in FIG. 5, this extra tooth split portion is left as the auxiliary dummy vibrator 51. That is, the dummy vibrator 28 includes a main dummy vibrator 50 as a main body and an auxiliary dummy vibrator 51 located on the outer side in the vibrator arrangement direction than the main dummy vibrator 50. Then, the main dummy vibrator 50 and the auxiliary dummy vibrator 51 are simultaneously chamfered to form a chamfered portion 42 in the main dummy vibrator 50 and a chamfered portion 52 in the auxiliary dummy vibrator 51, respectively. These chamfered portions 42 and 52 are shaped such that the front corner portion of the main dummy vibrator 50 and the corner portion on the outer side in the row direction at the front end portion of the auxiliary dummy vibrator 51 are cut off obliquely. With this configuration, the outer surface 50a of the main dummy vibrator 50 positioned on the tip side of the auxiliary dummy vibrator 51 is used as a positioning surface.
In the present embodiment, the chamfered portion 42 of the main dummy vibrator 50 and the chamfered portion 52 of the auxiliary dummy vibrator 51 are obliquely chamfered and positioned on a straight line, but the chamfered shape is the same as in this embodiment. Not limited to.
[0056]
In this configuration, when the vibrators 28 and 29 are divided, the outermost vibrator in the vibrator arrangement direction that has been removed conventionally is used as the auxiliary dummy vibrator 51. It is possible to omit the step of removing the vibrator located at the outermost part by removing the vibrator and improving the productivity.
[0057]
Further, in the present embodiment, the positioning step portion 53 that contacts the outer surface 50 a of the main dummy vibrator 50 is provided on the wall surface 5 a of the housing empty portion 5 on which the main dummy vibrator 50 that constitutes the dummy vibrator 28 contacts. It is protruding. The piezoelectric vibrator unit 4 is positioned by bringing the outer surface 50a of the main dummy vibrator 50 into contact with the contact surface 53a of the positioning step 53. As a result, the piezoelectric vibrator unit 4 can be positioned while the auxiliary dummy vibrator 51 remains.
[0058]
By the way, the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, with respect to the piezoelectric vibrator group 21, in each of the above-described embodiments, the vibrators 28 and 29 are completely separated from each other, and the base end portion is joined onto the fixed plate 22 to form a comb shape. However, it is also possible to provide an uncut portion at the base end portion of each of the vibrators 28 and 29 to form a comb-like vibrator group. For example, as shown in FIG. 6A, in the case of cutting from the free end side of the vibrator to the base end side, the cut surface 61 is inclined obliquely from the joint end portion to the fixing plate 22 to the base end portion of the piezoelectric vibrator. The proximal end portion may be left uncut so that there exists. Further, as shown in FIG. 6B, only the free end portion may be cut into the vibrator and the base end portion may be left uncut so that the cut surface 62 exists up to the joint portion with the fixing plate 22.
As described above, when the piezoelectric vibrator is divided into comb-like teeth, the drive vibration is not disturbed by inhibiting the deformation characteristics of the drive vibrators 29 by separating the piezoelectric vibrator by leaving the joint surface to the fixed plate 22. The fixing strength of the elements 29... And the dummy vibrators 28 can be increased.
[0059]
Moreover, you may make it provide said escape area S also in the case 2 side. For example, as shown in FIG. 7, the tapered shape of the case 2 is reduced toward the storage space 5 toward the base end side in a state where the case 2 is in communication with the storage space 5 at the distal end surface portion that contacts the stainless steel plate 15. A recess 81 is formed. By providing the recess 81 in this way, excess adhesive can be stored in the escape region S ′ (buffer region) formed by the recess 81, and the outflow of excess adhesive can be prevented more reliably. can do. As a result, poor adhesion of the piezoelectric vibrator unit 4 (piezoelectric vibrators 28 and 29) can be reliably prevented.
[0060]
Further, in this configuration, the parting line 44 at the time of molding the case 2 is located at the base end of the recess 81 (the end opposite to the flow path unit 3 side). Accordingly, the burr at the time of molding is formed on the rear side of the contact position between the tip surface portion 28d of the dummy vibrator 28 and the stainless steel plate 15, and the dummy vibrator 28 and the stainless steel plate 15 (flow path unit 3) It is also possible to prevent a problem that the burr is sandwiched between the two.
[0061]
【The invention's effect】
As described above, according to the present invention, the following excellent effects can be obtained.
That is, the vibrator at the end in the row direction is configured as a dummy vibrator for positioning the vibrator, and the corner portion outside the row in the row direction at the tip of the dummy vibrator is removed. An empty area can be used as an escape area.In this escape area, adhesive that has flowed out from the overlapping surface of the case and the flow path unit toward the storage empty section, or burrs generated at the opening edge of the storage empty section during molding. Etc. can be stored. For this reason, it can prevent that the adhesive agent, a burr | flash, etc. which flowed out are inserted | pinched, and a piezoelectric vibrator unit can be reliably attached to the regular position in an accommodation empty part. Therefore, the vibrator can be securely bonded.
[0062]
Further, since the corner portion is removed by chamfering, the insertion property of the piezoelectric vibrator unit into the case can be improved, and damage to the dummy vibrator can be effectively prevented.
[0063]
Further, a dummy vibrator forming member separate from the piezoelectric vibrator is provided on the outer side in the plane of the dummy vibrator, and the dummy vibrator forming member is made of a material having higher toughness than the constituent material of the piezoelectric vibrator. As a result, the bending strength of the dummy vibrator increases. Furthermore, by chamfering the tip portion of the dummy vibrator forming member, the insertion property of the piezoelectric vibrator unit into the case can be improved, and damage to the dummy vibrator can be prevented more reliably.
[0064]
In addition, a case in which an accommodation space that can accommodate the piezoelectric vibrator unit is provided, and an inclined guide portion that guides the dummy vibrator is formed on the wall surface of the accommodation space where the dummy vibrator abuts. In this case, since the dummy vibrator is guided along the inclined guide portion, the piezoelectric vibrator unit can be reliably positioned at a predetermined position in the housing empty portion.
[0065]
Further, in the method for manufacturing a piezoelectric vibrator unit, when the chamfering process is performed before the firing process, the laminate has toughness, and therefore, the chamfering process is easily performed using, for example, a press apparatus or a shearing apparatus. And manufacturing man-hours can be minimized. In addition, after performing the firing process, if the chamfering process is performed in the vibrator creating process in which the plate-shaped laminate is divided into comb teeth, the dummy vibrator can be chamfered without increasing the manufacturing process. it can.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing main parts of a piezoelectric vibrator unit and an ink jet recording head according to a first embodiment of the present invention.
2 is a view taken along line AA in FIG.
FIG. 3 is a cross-sectional view showing a laminated structure of piezoelectric vibrator units.
FIG. 4 is a schematic diagram illustrating a main part of a piezoelectric vibrator unit according to a second embodiment.
FIG. 5 is a schematic view illustrating a main part of a piezoelectric vibrator unit according to a third embodiment.
FIGS. 6A and 6B are diagrams for explaining a cut line at the time of tooth splitting. FIGS.
FIG. 7 is a cross-sectional view showing an embodiment in which a recess is provided in a case.
FIGS. 8A and 8B are explanatory views showing a method of manufacturing a piezoelectric vibrator unit according to the present invention, respectively.
[Explanation of symbols]
1 Recording head
2 cases
3 Channel unit
4 Piezoelectric vibrator unit
5 accommodation space
6 Ink supply pipe
7 Flow path forming plate
8 Nozzle plate
9 Elastic plate
10 Nozzle opening
11 Reservoir
12 Pressure chamber
13 Ink supply port
14 Elastic membrane
15 Stainless steel plate
16 island
17 Elastic part
21 transducer group
22 Fixing plate
23a Free end
23b Base end
24 Flexible cable
28 Dummy vibrator
29 Drive vibrator
31 Piezoelectric material
32 Common internal electrodes
33 Individual internal electrodes
36 Individual external electrodes
37 Common external electrode
41 Laminate
42 Chamfer
43 Inclination guide
44 Parting line
50 Main dummy vibrator
51 Auxiliary dummy vibrator
52 Chamfer
53 Positioning step
61 Cut surface
62 Cut surface
70 Dummy vibrator body
71 Dummy vibrator forming member
72 Chamfer
81 depression
91 Both corners on the free end of the laminate
92 Chamfer
S, S 'escape area
D Step
θ1, θ2 tilt angle

Claims (10)

In a piezoelectric vibrator unit including a piezoelectric vibrator group in which a plurality of piezoelectric vibrators are arranged in a row,
Piezoelectric vibrations characterized in that the vibrator at the end in the row direction is configured as a dummy vibrator for positioning the vibrator, and the corner portion outside the row in the row direction at the tip of the dummy vibrator is removed by chamfering. Child unit.   2. The piezoelectric vibrator unit according to claim 1, wherein the piezoelectric vibrator group is a comb-like vibrator group divided into comb teeth.   The dummy vibrator is composed of a dummy vibrator main body and a dummy vibrator forming member attached outside the dummy vibrator main body in the row direction, and the dummy vibrator forming member is a constituent material of the piezoelectric vibrator. 3. The piezoelectric vibrator unit according to claim 1, wherein the piezoelectric vibrator unit is made of a material having higher toughness.   4. The piezoelectric vibrator unit according to claim 3, wherein a tip portion of the dummy vibrator forming member is chamfered.   The dummy vibrator is composed of a main dummy vibrator and an auxiliary dummy vibrator provided outside the main dummy vibrator in the row direction, and the auxiliary dummy vibrator is chamfered together with the main dummy vibrator. 3. The piezoelectric vibrator unit according to claim 1, wherein the outer surface of the main dummy vibrator on the tip side of the auxiliary dummy vibrator is used as a positioning surface. A piezoelectric vibrator unit according to any one of claims 1 to 5, a flow path unit including an elastic plate constituting a part of a sealing member for a pressure chamber communicating with a nozzle opening, and a piezoelectric vibrator unit And a case where the flow path unit is joined to the tip.
An ink jet recording head, wherein positioning is performed by bringing the outer surface of the dummy vibrator into contact with the wall surface of the housing space, and the piezoelectric vibrator unit is attached to the case.   The ink jet recording head according to claim 6, wherein an inclined guide portion that guides the dummy vibrator is formed on a wall surface of the accommodation space where the dummy vibrator abuts.   7. The ink jet recording head according to claim 6, wherein a positioning step portion that abuts on the outer surface of the dummy vibrator is provided on the wall surface of the housing empty space on which the dummy vibrator abuts. A laminate creation step of creating a plate-like laminate by sandwiching a piezoelectric body between electrodes;
A chamfering step of chamfering both corners on the side to be a free end in the laminate;
A firing step of firing the chamfered laminate,
Piezoelectric vibrations characterized in that a sintered vibrator is cut to create a drive vibrator and a vibrator creation process for creating a dummy vibrator for vibrator positioning at the end of the vibrator arrangement direction. Child unit manufacturing method. A laminate creation step of creating a plate-like laminate by sandwiching a piezoelectric body between electrodes;
A firing step of firing the laminate;
Chamfer both corners on the side that will be the free end of the fired laminate, and cut this laminate to create a drive vibrator. At the end of the vibrator array, dummy vibration for positioning the vibrator A method of manufacturing a piezoelectric vibrator unit, wherein a vibrator creating process for creating a child is sequentially performed.

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