BACKGROUND OF THE INVENTION
[0001] This invention relates to an ink jet recording head wherein a piezoelectric element
is formed via a diaphragm in a part of each of pressure generating chambers communicating
with nozzle orifices for jetting ink drops and ink drops are jetted by displacement
of the piezoelectric element, and an ink jet recording apparatus comprising the ink
jet recording head.
[0002] The following two types of ink jet recording heads, each wherein a part of a pressure
generating chamber communicating with a nozzle orifice for jetting an ink drop is
formed of a diaphragm and the diaphragm is deformed by a piezoelectric element for
pressurizing ink in the pressure generating chamber for jetting an ink drop through
the nozzle orifice, are commercially practical: One uses a piezoelectric actuator
in a vertical vibration mode in which the piezoelectric element is expanded and contracted
axially and the other uses a piezoelectric actuator in a deflection vibration mode.
[0003] With the former, the volume of the pressure generating chamber can be changed by
abutting an end face of the piezoelectric element against the diaphragm and a head
appropriate for high-density printing can be manufactured, but a difficult step of
dividing the piezoelectric element like comb teeth matching the arrangement pitch
of the nozzle orifices and work of positioning and fixing the piezoelectric element
divisions in the pressure generating chambers are required and the manufacturing process
is complicated.
[0004] In contrast, with the latter, the piezoelectric element can be created and attached
to the diaphragm by executing a comparatively simple process of putting a green sheet
of a piezoelectric material matching the form of the pressure generating chamber and
baking it, but a reasonable area is required because deflection vibration is used;
high-density arrangement is difficult to make.
[0005] On the other hand, to solve the problem of the latter recording head, Japanese Patent
Publication No. 5-286131A proposes an art wherein an uniform piezoelectric material
layer is formed over the entire surface of a diaphragm according to a film formation
technique and is divided to a form corresponding to a pressure generating chamber
according to a lithography technique for forming a piezoelectric element separately
for each pressure generating chamber.
[0006] This eliminates the need for work of putting the piezoelectric element on the diaphragm
and the piezoelectric element can be created by the lithography method, an accurate
and simple technique. In addition, the piezoelectric element can be thinned and high-speed
drive is enabled. In this case, with the piezoelectric material layer provided on
the whole surface of the diaphragm, at least only upper electrodes are provided in
a one-to-one correspondence with the pressure generating chambers, whereby the piezoelectric
actuator corresponding to each pressure generating chamber can be driven.
[0007] In such an ink jet recording head, generally a reservoir which becomes an ink chamber
common to pressure generating chambers is formed by depositing a plurality of substrates
on each other, and ink is supplied from the reservoir to the pressure generating chambers.
To hold the internal pressure of the reservoir constant, the reservoir is provided
with a compliance section for absorbing pressure change when a piezoelectric element
is driven.
[0008] However, a large number of substrates used to form the reservoir are required; particularly
a large number of substrates deposited to form the compliance section are required,
increasing material and assembly costs.
[0009] The ink jet recording head as described above is intended to have a large number
of nozzles and it is necessary to form the reservoir in size capable of sufficiently
supplying ink to the pressure generating chambers accordingly; the strength of the
substrates forming the reservoir is degraded inevitably. Thus, if heat is applied
to the substrates at an installation step, the substrates are warped due to thermal
expansion and a crack occurs.
[0010] To use silicon for the substrate for defining each pressure generating chamber, it
is difficult to bond at a high temperature because of the difference from other substrates
in thermal expansion coefficient and the number of assembly steps is increased.
[0011] EP-A-707 961 discloses an ink jet recording head with a piezoelectric element holding
section (36).
SUMMARY OF THE INVENTION
[0012] It is therefore an object of the invention to provide an ink jet recording head for
preventing deformation and cracking of substrates with a structure simplified and
manufacturing costs reduced, and an ink jet recording apparatus comprising the ink
jet recording head.
[0013] In order to achieve the above object, an ink jet recording head as defined in the
appended claims is provided.
[0014] According to the invention the number of substrates deposited for forming the reservoir
can be reduced and the structure can be simplified. In addition, the piezoelectric
elements are hermetically sealed in the piezoelectric element holding section and
destruction of the piezoelectric elements caused by the external environment is prevented,
and ink is supplied from the reservoir common to the pressure generating chambers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In the accompanying drawings:
Fig. 1 is an exploded perspective view of an ink jet recording head according to a
first embodiment of the invention;
Figs. 2A and 2B are a plan view and a sectional view of the ink jet recording head
according to the first embodiment of the invention;
Figs. 3A and 3B are a plan view and a sectional view to show a modified example of
the ink jet recording head according to the first embodiment of the invention;
Fig. 4 is a sectional view to show a modified example of the ink jet recording head
according to the first embodiment of the invention;
Fig. 5 is a sectional view to show a modified example of the ink jet recording head
according to the first embodiment of the invention;
Figs. 6A and 6B is a plan view and a sectional view to show a modified example of
the ink jet recording head according to the first embodiment of the invention;
Figs. 7A and 7B are a plan view and a sectional view of an ink jet recording head
according to a second embodiment of the invention;
Figs. 8A and 8B are a sectional view of an ink jet recording head and a schematic
diagram of a flexible film according to a third embodiment of the invention;
Figs. 9A and 9B are a plan view and a sectional view of an ink jet recording head
according to a fourth embodiment of the invention;
Fig. 10 is a perspective view to show a modified example of the ink jet recording
head according to the fourth embodiment of the invention;
Fig. 11 is a perspective view to show a modified example of the ink jet recording
head according to the fourth embodiment of the invention;
Fig. 12 is a sectional view of an ink jet recording head according to a fifth embodiment
of the invention;
Fig. 13 is a sectional view to show a modified example of the ink jet recording head
according to the fifth embodiment of the invention;
Figs. 14A and 14B are a plan view and a sectional view of an ink jet recording head
according to a sixth embodiment of the invention;
Fig. 15 is a sectional view to show a modified example of the ink jet recording head
according to the sixth embodiment of the invention;
Figs. 16A and 16B are a plan view and a sectional view of an ink jet recording head
according to a seventh embodiment of the invention;
Figs. 17A and 17B are a plan view and a sectional view of an ink jet recording head
according to an eighth embodiment of the invention;
Figs. 18A and 18B are a plan view and a sectional view to show a modified example
of the ink jet recording head according to the eighth embodiment of the invention;
Figs. 19A and 19B are a plan view and a sectional view to show a modified example
of the ink jet recording head according to the eighth embodiment of the invention;
Figs. 20A and 20B are a plan view and a sectional view of an ink jet recording head
according to a ninth embodiment of the invention;
Fig. 21 is a sectional view to show a modified example of the ink jet recording head
according to the ninth embodiment of the invention;
Fig. 22 is a sectional view to show a modified example of the ink jet recording head
according to the ninth embodiment of the invention;
Figs. 23A and 23B are a plan view and a sectional view of an ink jet recording head
according to a tenth embodiment of the invention; and
Fig. 24 is a schematic diagram of an ink jet recording apparatus according to one
embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] Referring now to the accompanying drawings, there are shown preferred embodiments
of the invention.
First embodiment:
[0017] Fig. 1 is an exploded perspective view to show an ink jet recording head according
to a first embodiment of the invention. Figs. 2A and 2B are a plan view and a sectional
view of the ink jet recording head shown in Fig. 1.
[0018] As shown in the figure, a channel forming substrate 10 is made of a silicon monocrystalline
substrate of a <110> plane orientation in the embodiment. Normally, a substrate about
150-300 µm thick is used as the channel forming substrate 10; preferably a substrate
about 180-280 µm thick, more preferably a substrate about 220 µm thick is used because
the arrangement density can be made high while the rigidity of a partition between
contiguous pressure generating chambers is maintained.
[0019] The channel forming substrate 10 is formed on one face with an opening face and on
an opposite face with an elastic film 50 of 1-2 µm thick made of silicon dioxide previously
formed by thermal oxidation.
[0020] On the other hand, the channel forming substrate 10 is formed on the opening face
with pressure generating chambers 12 which are partitioned by a plurality of partitions
11 and are placed side by side in a width direction by anisotropically etching the
silicon monocrystalline substrate and is formed on the outside in the longitudinal
direction thereof with a communication section 13 communicating with a reservoir section
of a reservoir forming substrate described later and forming a part of a reservoir
100 which becomes an ink chamber common to the pressure generating chambers 12; the
communication section 13 communicates with one end part of each pressure generating
chamber 12 in the longitudinal direction thereof via an ink supply port 14.
[0021] The anisotropic etching is executed by using the nature that if the silicon monocrystalline
substrate is immersed in an alkaline solution such as KOH, it gradually erodes, a
first <111> plane perpendicular to a <110> plane and a second <111> plane forming
about 70 degrees with the first <111> plane and forming about 35 degrees with the
<110> plane appear, and the etching rate of the <111> plane is about 1/180 that of
the <110> plane. By the anisotropic etching, accurate work can be executed based on
depth work like a parallelogram formed by the two first <111> planes and the two second
<111> planes tilted, and the pressure generating chambers 12 can be arranged at a
high density.
[0022] In the embodiment, the long sides of each pressure generating chamber 12 are formed
by the first <111> planes and the short sides are formed by the second <111> planes.
The pressure generating chambers 12 are formed by etching the silicon monocrystalline
substrate almost passing through the channel forming substrate 10 to the elastic film
50. The amount of immersing the elastic film 50 in the alkaline solution for etching
the silicon monocrystalline substrate is extremely small. Each ink supply port 14
communicating with one end of each pressure generating chamber 12 is formed shallower
than the pressure generating chamber 12 for holding the flow passage resistance of
ink flowing into the pressure generating chamber 12 constant. That is, the ink supply
ports 14 are formed by etching the silicon monocrystalline substrate to an intermediate
point in the thickness direction (half etching). The half etching is executed by adjusting
the etching time.
[0023] A nozzle plate 16 formed with nozzle orifices 15 communicating with the pressure
generating chamber 12 on the opposite side of the pressure generating chamber 12 to
the ink supply ports 14 is fixedly secured to the opening face side of the channel
forming substrate 10 via an adhesive, a thermal-deposited film, etc. The nozzle plate
16 is made of glass ceramics, stainless steel, or the like having a thickness of 0.1-1
mm and a linear expansion coefficient of 2.5-4.5 [x 10
-6/°C] at 300°C or less, for example. One face of the nozzle plate 16 covers fully one
face of the channel forming substrate 10, namely, the nozzle plate 16 also serves
as a reinforcing plate for protecting the silicon monocrystalline substrate from shock
and external force. The nozzle plate 16 may be formed of a material having substantially
the same thermal expansion coefficient as the channel forming substrate 10 has. In
this case, the channel forming substrate 10 and the nozzle plate 16 become deformed
substantially in the same manner due to heat and thus can be joined easily using a
thermosetting adhesive, etc.
[0024] The size of each pressure generating chamber 12 for giving ink drop jet pressure
to ink and the size of each nozzle orifice 15 for jetting ink drops are optimized
in response to the jetted ink drop amount, jet speed, and jet frequency. For example,
to record 360 ink drops per inch, the nozzle orifice 15 needs to be made accurately
with a diameter of several ten µm.
[0025] On the other hand, a lower electrode film 60, for example, about 0.2 µm thick, a
piezoelectric film 70, for example, about 1 µm thick, and an upper electrode film
80, for example, about 0.1 µm thick are deposited on the elastic film 50 on the opposite
side to the opening face of the channel forming substrate 10 by a process described
later, making up a piezoelectric element 300. This piezoelectric element 300 refers
to the portion containing the lower electrode film 60, the piezoelectric film 70,
and the upper electrode film 80. Generally, one electrode of the piezoelectric element
300 is used as a common electrode and the other electrode and the piezoelectric film
70 are patterned for each pressure generating chamber 12. A portion made up of the
electrode and the piezoelectric film 70 patterned where piezoelectric distortion occurs
as a voltage is applied to both electrodes is referred to as a piezoelectric active
part 320. In the embodiment, the lower electrode film 60 is used as the common electrode
of the piezoelectric element 300 and the upper electrode film 80 is used as a discrete
electrode of the piezoelectric element 300, but the lower electrode film 60 may be
used as a discrete electrode and the upper electrode film 80 may be used as the common
electrode for convenience of a drive circuit and wiring. In any case, the piezoelectric
active part is formed for each pressure generating chamber 12. Here, the piezoelectric
element 300 and the diaphragm displaced by drive of the piezoelectric element 300
are collectively called a piezoelectric actuator. In the above-described example,
the elastic film 50 and the lower electrode film 60 act as the diaphragm, but the
lower electrode film may also serve as the elastic film.
[0026] A reservoir forming substrate 20 having a reservoir section 21 forming at least a
part of the reservoir 100 is joined to the piezoelectric element 300 side of the channel
forming substrate 10. In the embodiment, the reservoir section 21 is formed in the
width direction of the pressure generating chambers 12 piercing the reservoir forming
substrate 20 in the thickness direction thereof and is made to communicate with the
communication section 13 of the channel forming substrate 10 and forms a part of the
reservoir 100 which becomes an ink chamber common to the pressure generating chambers
12 as described above.
[0027] Preferably, a material having substantially the same thermal expansion coefficient
as the channel forming substrate 10 has, such as glass or ceramic material, is used
as the reservoir forming substrate 20. In the embodiment, the reservoir forming substrate
20 is formed using a silicon monocrystalline substrate of the same material as the
channel forming substrate 10, so that even if the reservoir forming substrate 20 and
the channel forming substrate 10 are bonded at a high temperature using a thermosetting
adhesive, they can be bonded reliably as in the case of the above-described nozzle
plate 16. Therefore, the manufacturing process can be simplified.
[0028] Further, a compliance substrate 30 made up of a sealing film 31 and a fixing plate
32 is joined to the reservoir forming substrate 20. The sealing film 31 is made of
a material having low rigidity and flexibility (for example, polyphenylene sulfide
(PPS) film of 6 µm thick) and seals one side of the reservoir section 21. The fixing
plate 32 is formed of a hard material of metal, etc., (for example, stainless steel
(SUS) of 30 µm thick, or the like). Since the area of the fixing plate 32 opposed
to the reservoir 100 forms an opening section 33 made by completely removing a part
of the seal plate 32 in the thickness direction thereof, one side of the reservoir
100 is sealed only with the sealing film 31 having flexibility and becomes a flexible
section 22 that can become deformed as internal pressure changes.
[0029] An ink introduction port 25 for supplying ink to the reservoir 100 is formed on the
compliance substrate 30 on the outside substantially at the center in the longitudinal
direction of the reservoir 100. Further, the reservoir forming substrate 20 is formed
with an ink introduction passage 26 for making the ink introduction port 25 and the
side wall of the reservoir 100 communicate with each other. In the embodiment, ink
is supplied to the reservoir 100 through one ink introduction port 25 and one ink
introduction passage 26, but the scope of the invention is not limited to it. For
example, more than one ink introduction port and more than one ink introduction passage
may be provided in response to any desired ink supply amount or the opening area of
the ink introduction port may be enlarged for enlarging the ink flow passage.
[0030] Normally, when ink is supplied from the ink introduction port 25 to the reservoir
100, pressure change occurs in the reservoir 100, for example, due to an ink flow
at the driving time of the piezoelectric element 300 or ambient heat, etc. However,
one side of the reservoir 100 is sealed only with the sealing film 31 and becomes
the flexible section 22 as described above, thus the flexible section 22 becomes deflection-deformed
for absorbing the pressure change. Therefore, the inside of the reservoir 100 is always
held at a constant pressure. Other portions are held in sufficient strength by means
of the fixing plate 32. In the embodiment, the number of the substrates forming the
reservoir 100, etc., can be decreased, thus the material and assembly costs, etc.,
can be reduced.
[0031] On the other hand, in a state in which a space is provided to such an extent that
motion of the piezoelectric element 300 is not inhibited, the area of the reservoir
forming substrate 20 opposed to the piezoelectric element 300 is formed with a piezoelectric
element holding section 24 capable of hermetically sealing the space, and at least
the piezoelectric active part 320 of the piezoelectric element 300 is hermetically
sealed in the piezoelectric element holding section 24. In the embodiment, the piezoelectric
element holding section 24 is formed in size covering a plurality of piezoelectric
elements 300 placed side by side in a width direction.
[0032] Thus, the reservoir forming substrate 20 forms the reservoir 100 and also serves
as a capping member for insulating the piezoelectric elements 300 from the external
environment; it can prevent the piezoelectric elements 300 from being destroyed due
to the external environment of a moisture content, etc. In the embodiment, the inside
of the piezoelectric element holding section 24 is sealed. However, for example, the
space in the piezoelectric element holding section 24 is evacuated or is placed in
a nitrogen or argon atmosphere, etc., whereby the inside of the piezoelectric element
holding section 24 can be held at low humidity and destruction of the piezoelectric
elements 300 can be prevented more reliably.
[0033] In the embodiment, the piezoelectric film 70 and the upper electrode film 80 of the
piezoelectric element 300 thus hermetically sealed by means of the piezoelectric element
holding section 24 are extended from one end part of the pressure generating chamber
12 in the longitudinal direction thereof to the outside of the reservoir forming substrate
20 on the channel forming substrate 10 and are connected to external wiring 40, such
as a flexible cable, on an exposed portion 10a where the face of the joint side of
the channel forming substrate 10 to the reservoir forming substrate 20 is exposed.
That is, wiring is extended from the piezoelectric element 300 to the outside of the
reservoir forming substrate 20, whereby the piezoelectric element 300 and the external
wiring can be connected easily.
[0034] With the described ink jet recording head of the embodiment, ink is taken in through
the ink introduction port 25 connected to external ink supply means (not shown) and
the inside of the recording head from the reservoir 100 to the nozzle orifices 15
is filled with ink, then a voltage is applied to the part between the lower electrode
film 60 and the upper electrode film 80 corresponding to each pressure generating
chamber 12 according to a record signal from an external drive circuit (not shown)
for deflection-deforming the elastic film 50, the lower electrode film 60, and the
piezoelectric film 70, thereby raising pressure in the corresponding pressure generating
chamber 12 and jetting an ink drop through the corresponding nozzle orifice 15.
[0035] In the embodiment, the piezoelectric element holding section 24 of the reservoir
forming substrate 20 is formed so as to cover all piezoelectric elements 300 placed
side by side in the width direction, but the scope of the invention is not limited
to it. For example, as shown in Figs. 3A and 3B, the piezoelectric element holding
section 24 may be divided by partition walls 27 into separate piezoelectric element
holding sections 24A for hermetically sealing the piezoelectric elements 300 with
the corresponding piezoelectric element holding sections 24A, whereby the partition
wall 27 is joined to the portion of the channel forming substrate 10 corresponding
to a side wall 12a of each pressure generating chamber 12, the rigidity of the peripheral
wall of the pressure generating chamber 12 is enhanced, and falling down of the peripheral
wall when the piezoelectric element 300 is driven can be suppressed. According to
the composition, destruction of the piezoelectric element 300 can also be prevented
as in the above-described embodiment, needless to say.
[0036] In the embodiment, the piezoelectric film 70 and the upper electrode film 80 are
extended to the outside of the reservoir forming substrate 20 and the upper electrode
film 80 and the external wiring 40 are connected, but the scope of the invention is
not limited to it. For example, as shown in Fig. 4, the piezoelectric elements 300
may be patterned in the area facing the pressure generating chambers 12 and a lead
electrode 90 may be extended from the upper electrode film 80 via an insulation film
85 to the exposed portion 10a outside the reservoir forming substrate 20 and be connected
to the external wiring 40 in the proximity of the end portion thereof.
[0037] Thus, the lead electrode 90 is extended from the upper electrode film 80 to the outside
of the reservoir forming substrate 20 and is connected to the external wiring 40,
whereby a gap with the elastic film 50 when the reservoir forming substrate 20 is
bonded becomes only several µm and the piezoelectric elements 300 can be hermetically
sealed in the piezoelectric element holding section 24 more reliably.
[0038] In the embodiment, the channel forming substrate 10 is so formed as to be larger
than the reservoir forming substrate 20 and the piezoelectric elements 300 and the
external wiring 40 are connected on the exposed portion 10a of the channel forming
substrate 10, but the scope of the invention is not limited to it. For example, as
shown in Fig. 5, the reservoir forming substrate 20 may be so formed as to be larger
than the channel forming substrate 10, the face on the joint side of the reservoir
forming substrate 20 to the channel forming substrate 10 may be exposed to form an
exposed portion 20a, and the piezoelectric elements 300 and the external wiring may
be connected on the exposed portion 20a.
[0039] Further, in the embodiment, the communication section 13 forming a part of the reservoir
100 via the ink supply ports 14 is placed on the end part side of the channel forming
substrate 10 opposite to the nozzle orifices 15 of the pressure generating chambers
12, but the scope of the invention is not limited to it. For example, as shown in
Figs. 6A and 6B, the reservoir 100 basically may be formed only of the reservoir section
21 of the reservoir forming substrate 20, and the pressure generating chambers 12
and the reservoir 100 may be made to communicate with each other via a communication
passage 18 relatively narrower than the flow passage of the reservoir 100 in the channel
forming substrate 10. In the composition, when ink is supplied to the pressure generating
chamber 12, the flow velocity of the ink is maintained, so that mixing of bubbles
can be prevented and good ink jetting can be executed.
[0040] Figs. 7A and 7B are a plan view and a sectional view of an ink jet recording head
according to a second embodiment of the invention.
[0041] The second embodiment is an example wherein a flexible section 22 is placed in a
channel forming substrate 10 rather than in the area of a reservoir section 21 opposite
to the channel forming substrate 10.
[0042] Particularly, as shown in Figs. 7A and 7B, in the embodiment, the channel forming
substrate 10 in the area corresponding to the reservoir section 21 is formed with
a through section 18 not communicating with pressure generating chambers in the width
direction of the pressure generating chambers, and at least the space between the
through section 18 and the reservoir section 21 is closed with a flexible film 110
that can be elastically deformed in the thickness direction thereof, forming the flexible
section 22.
[0043] On the other hand, a fixing plate 32A made of a hard material of metal, etc., such
as stainless steel (SUS), is joined to the face on the opposite side of a reservoir
forming substrate 20 to the channel forming substrate 10, sealing one side of a reservoir
100.
[0044] If pressure change occurs in the reservoir 100 as a piezoelectric element 300 is
driven or for any other reason, like the above-described flexible section 22, the
flexible film 110 becomes elastically deformed, thereby absorbing the pressure change,
whereby the internal pressure of the reservoir 100 is always suppressed to a given
value or less and a good ink jet characteristic is maintained.
[0045] In the embodiment, an elastic film 50 and a lower electrode film 60, a piezoelectric
film 70, and an upper electrode film 80 making up the piezoelectric element 300 are
placed on the channel forming substrate 10 in the area corresponding to the reservoir
section 21, and become the flexible film 110 in the area facing the through section
18. The flexible film 110 made up of the films is about 3 µm thick and functions sufficiently
as a compliance section.
[0046] Preferably, the flexible film 110 contains a film having a tensile stress in all
plane direction. Particularly, preferably the stress of the whole films making up
the flexible film 110 is strong in the tensile direction and does not buckle, so that
excessive deformation of the flexible film 110 is suppressed and destruction of the
flexible film 110 can be prevented.
[0047] In the embodiment, the flexible film 110 is made up only of the elastic film 50 and
the films making up the piezoelectric element 300 and can be formed as the piezoelectric
element 300 is formed. The through section 18 can also be etched together with the
pressure generating chambers 12 and be formed and thus can be formed easily without
increasing the manufacturing steps.
[0048] In the embodiment, the flexible film 110 consists of the elastic film 50, the lower
electrode film 60, the piezoelectric film 70, and the upper electrode film 80, but
the scope of the invention is not limited to it. For example, the flexible film 110
may be made up of the elastic film 50 and at least one of the layers making up the
piezoelectric element 300; in any way, it may be a film having flexibility and a predetermined
strength. However, when the elastic film is formed of silicon dioxide as in the embodiment,
if the flexible film 110 is made only of an elastic film, a low strength is provided;
the composition is not preferred. A separate film made of any other material may be
provided as the flexible film 110, needless to say.
[0049] Figs. 8A and 8B are a sectional view of the main part of an ink jet recording head
and a schematic diagram of a flexible film according to a third embodiment of the
invention.
[0050] As shown in Figs. 8A and 8B, the third embodiment is similar to the second embodiment
except that a beam member 111 made up of projection bars extended in a plane direction
is provided on the surface on the channel forming substrate side of a flexible film
110 which becomes a flexible section 22.
[0051] The beam member 111 is provided for enhancing the strength of the flexible film 110.
For example, in the embodiment, the beam member 111 is provided like a grid over the
whole surface of the flexible film 110 as shown in Fig. 8B. The area of the flexible
film 110 may be determined appropriately in response to the conditions of the material,
film thickness, etc., of the flexible film 110 so as to provide any desired strength
for the flexible film 110. At this time, to reliably absorb pressure change in a reservoir
100, preferably the portion of the flexible film 110 which becomes the actual flexible
part where the beam member 111 is not formed holds an area at least 10 times the area
of a pressure generating chamber.
[0052] The formation method of the beam member 111 is not limited; for example, to make
a through section 18 in a channel forming substrate 10, a predetermined mask pattern
is used for etching, whereby a portion where a part of the channel forming substrate
10 is left may be used as the beam member 111.
[0053] Thus, the flexible film 110 is provided with the beam member 111, whereby the strength
of the flexible film 110 can be increased. Therefore, the strength and compliance
of the flexible film 110 can be adjusted easily and with high accuracy by adjusting
the area of the beam member 111.
[0054] The form of the beam member 111 is not limited to a grid; it may be any other form,
such as a slanting grid, if the form is capable of holding predetermined compliance.
Of course, the strength and compliance of the flexible film 110 may be adjusted by
changing the size of the through section 18.
[0055] Figs. 9A and 9B are a plan view and a sectional view of an ink jet recording head
according to a fourth embodiment of the invention.
[0056] As shown in Figs. 9A and 9B, the fourth embodiment is similar to the first embodiment
except that a reservoir section 21 forming a part of a reservoir 100 is formed with
a reinforcing member 28 for holding the rigidity of a reservoir forming substrate
20.
[0057] That is, in the fourth embodiment, the reservoir section 21 is defined in the reservoir
forming substrate 20 and at least one reinforcing member 28 (for example, two beam-like
reinforcing members 28 in the embodiment) is placed between side walls facing each
other. The reinforcing member 28 is formed along the longitudinal direction of a piezoelectric
element 300 on the surface side opposite to the joint face of the reservoir section
21 to a channel forming substrate 10. The reinforcing member 28 is formed by half-etching
the reservoir forming substrate 20 from the joint face side to the channel forming
substrate 10, and is thinner than other portions. Preferably, the reinforcing member
28 is made an area as wide as possible in the area range to such an extent that a
flexible section 22 is capable of uniformly holding the internal pressure of the reservoir
100.
[0058] . Thus, in the embodiment, the beam-like reinforcing members 28 are placed between
the side walls defining the reservoir 100 and the rigidity of the reservoir section
21 is enhanced. Thus, if the volume of the reservoir section 21 is made relatively
large, deformation such as a warp of the reservoir forming substrate caused by a thermal
stress at the installation time can be prevented and a crack of the reservoir forming
substrate caused by the deformation can be prevented. Therefore, the durability and
reliability of the head can be enhanced.
[0059] In the embodiment, the reinforcing members 28 are formed on the surface side opposite
to the joint face of the reservoir forming substrate 20 to the channel forming substrate
10, but the scope of the invention is not limited to it. For example, as shown in
Fig. 10, the reinforcing members 28 may be formed on the joint face side of the reservoir
forming substrate 20 to the channel forming substrate 10.
[0060] In the embodiment, the whole reinforcing member 28 is made thinner than other portions,
but the scope of the invention is not limited to it. For example, as shown in Fig.
11, the reinforcing member 28 basically may be formed with the same thickness as the
reservoir forming substrate 20 and a part of the joint face side to the channel forming
substrate 10 may be made a removal part 28a provided by removing a part in the thickness
direction. By adopting such a structure, the strength of the reservoir forming substrate
20 can be furthermore enhanced and deformation caused by heat at the installation
time can be prevented reliably without degrading the function of the reservoir 100.
[0061] Further, in the embodiment, the two reinforcing members 28 are provided, but the
scope of the invention is not limited to it. For example, one or three or more reinforcing
members 28 may be provided. In any way, the form of the reinforcing member 28 may
be a form capable of holding the compliance of the flexible section 22 to such an
extent that internal pressure change of the reservoir 100 can be absorbed.
[0062] Fig. 12 is a sectional view of the main part of an ink jet recording head according
to a fifth embodiment of the invention.
[0063] The fifth embodiment is an example wherein a compliance substrate 30A made of one
member is placed on a channel forming substrate 10. That is, as shown in Fig. 12,
the fifth embodiment is similar to the first embodiment except that a through hole
which becomes an ink introduction port 25 is made on the outside of a flexible section
22A having flexibility provided by removing a part of the area facing a reservoir
100 in the thickness direction of the area. Preferably, the material of the compliance
substrate 30A is a resin material having flexibility, such as fluororesin, silicone
family resin, or silicone rubber, so that the compliance substrate 30A can be formed
easily.
[0064] The manufacturing method of the compliance substrate 30A is not limited; for example,
the compliance substrate 30A can be formed by forming a resin layer of a predetermined
thickness on a silicon monocrystalline substrate forming a reservoir forming substrate
20, then forming the reservoir 100, etc., on the reservoir forming substrate 20 by
etching, etc., and further etching a part, etc., in the thickness direction of the
area of the resin layer opposed to the reservoir 100.
[0065] In the embodiment, the compliance substrate 30A is formed of a resin material, but
the scope of the invention is not limited to it. For example, as shown in Fig. 13,
a compliance substrate 30B may be made of a thin film of metal, ceramic, or the like
about 1-10 µm thick. In this case, the area opposed to the reservoir 100 can be made
a flexible section 22B having flexibility without removing a part in the thickness
direction. Therefore, the head can be manufactured more easily.
[0066] Figs. 14A and 14B are a plan view and a sectional view of an ink jet recording head
according to a sixth embodiment of the invention.
[0067] As shown in Figs. 14A and 14B, the sixth embodiment is similar to the first embodiment
except that a detection through hole 24a for detecting displacement of each piezoelectric
element 300 is made so as to across the pressure generating chambers 12 in such portion
corresponding to the piezoelectric elements 300 in such area of a reservoir forming
substrate 20 opposed to a piezoelectric element holding section 24.
[0068] In the composition, displacement of each piezoelectric element 300 can be checked,
for example, using laser beam, etc., before a compliance substrate 30 is joined onto
the reservoir forming substrate 20. Therefore, a failure of the piezoelectric element
300 can be found before the head is completed; the head manufacturing efficiency can
be enhanced. Since the detection through hole 24a is sealed with the compliance substrate
30, the piezoelectric element holding section 24 can be held in a hermetic seal state
as in the first embodiment.
[0069] The detection through hole 24a is not limited in size and may be formed at least
in the area facing the piezoelectric elements 300. Therefore, in the embodiment, it
is made like a groove in the row direction of the pressure generating chambers 12.
However, for example, the detection through hole 24a may be made a round hole for
each piezoelectric element 300 or the whole piezoelectric element holding section
may be made the through hole.
[0070] In the embodiment, the detection through hole 24a is sealed with the compliance substrate
30, but the scope of the invention is not limited to it. For example, as shown in
Fig. 15, the detection through hole 24a may be sealed only with a sealing film 31
having flexibility, namely, a fixing plate 32 in the area facing the detection through
hole 24a may be removed to form a flexible section 22C. Thus, if pressure change occurs
in the piezoelectric element holding section 24, the flexible section 22C becomes
deformed, thereby absorbing the pressure change; the inside of the piezoelectric element
holding section 24 can always be held at a constant pressure.
[0071] The sealing film 31 which becomes the flexible section 22C of the piezoelectric element
holding section 24 may be formed of a light transparent member, such as acrylic resin,
so that displacement of each piezoelectric element 300 can be detected with the piezoelectric
element 300 hermetically sealed in the piezoelectric element holding section 24. That
is, the piezoelectric elements 300 can be inspected at all times.
[0072] Figs. 16A and 16B are a plan view and a sectional view of an ink jet recording head
according to a seventh embodiment of the invention.
[0073] The seventh embodiment is another example of the wiring method of a piezoelectric
element 300. As shown in Fig. 16, a compliance substrate 30 is not placed in a part
on the opposite side of a reservoir forming substrate 20 to a reservoir 100 to form
an exposed portion 20b where the surface of the reservoir forming substrate 20 is
exposed. Wiring 29 is extended onto the exposed portion 20b of the reservoir forming
substrate 20 by wire bonding from an upper electrode film 80 of the piezoelectric
element 300 extended to the outside of the reservoir forming substrate 20, and the
end part of the extended wiring 29 is made an installation section 120 for connecting
the piezoelectric element 300 and external wiring 40. Further, the outside is molded
by an insulating member 95 of epoxy, etc., for example, for providing electric insulation.
The seventh embodiment is similar to the first embodiment in other points.
[0074] To connect the piezoelectric element 300 and the external wiring 40 on an exposed
portion where the surface of a channel forming substrate 10 is exposed as formerly,
the exposed portion requires a width of about 2.2-3.0 mm and the dimensions of the
head become a little large. In contrast, in the embodiment, the wiring 29 is extended
onto the exposed portion 20b of the reservoir forming substrate 20 by wire bonding
from an exposed portion 10a of a channel forming substrate 10 and is connected to
the external wiring 40. Thus, the exposed portion 10a of the channel forming substrate
10 can be made about 0.2 mm wide and the dimensions of the recording head can be made
smaller. Of course, according to the composition, advantages similar to those of the
first embodiment can also be provided.
[0075] Figs. 17A and 17B are a plan view and a sectional view of an ink jet recording head
according to an eighth embodiment of the invention.
[0076] The eighth embodiment is an example wherein a reservoir forming substrate 20 is formed
with a through groove via which a piezoelectric element 300 and external wiring are
connected. Particularly, as shown in Figs. 17A and 17B, in the embodiment, a piezoelectric
film 70 and an upper electrode film 80 of the piezoelectric element 300 are extended
to the top of the peripheral wall of a pressure generating chamber 12 in the longitudinal
direction thereof on the side of a nozzle orifice 15 and are sandwiched between a
channel forming substrate 10 and the reservoir forming substrate 20. A part of the
joint face of the reservoir forming substrate 20 to a compliance substrate 30 is made
an exposed portion 20b provided by exposing the surface as in the seventh embodiment,
and a through groove 35 extended in the direction in which the pressure generating
chambers 12 are placed side by side is formed in the area corresponding to the exposed
portion 20b and facing the upper electrode film 80 of the piezoelectric element 300.
Wiring 29 is extended by wire bonding onto the surface of the reservoir forming substrate
20 through the through groove 35 from the upper electrode film 80 of each piezoelectric
element 300, and the end part of the wiring 29 is made an installation section 120
for connecting the piezoelectric element 300 and external wiring 40 such as a flexible
cable.
[0077] In the composition, the wiring 29 is extended via the through groove 35, thus eliminating
the need for providing the exposed portion 10a at the end of the channel forming substrate
10 or the exposed portion 20a at the end portion of the reservoir forming substrate
20; the head can be more miniaturized.
[0078] In the embodiment, the through groove 35 is formed like a groove over the row of
the piezoelectric elements 300, but the scope of the invention is not limited to it.
For example, a through hole may be made separately for each piezoelectric element
300.
[0079] In the embodiment, the wiring 29 is extended by wire bonding from the upper electrode
film 80, but the scope of the invention is not limited to it. For example, as shown
in Figs. 18A and 18B, a conductive thin film of gold (Au), etc., may be formed on
the inner peripheral surface of the through groove 35 and on the top of the compliance
substrate 30 and may be patterned for each piezoelectric element 300, thereby providing
wiring 29A.
[0080] Further, for example, as shown in Figs. 19A and 19B, wiring 29B may be extended via
a joint face 20c and an outer face 20d of the reservoir forming substrate 20 to the
exposed portion 20b of the piezoelectric element 300 and the end part of the wiring
29B may be made the installation section 120 for connecting to the external wiring
40. To provide the wiring 29B, preferably a lead electrode 90 is extended from the
upper electrode film 80 to the joint face 20c of the reservoir forming substrate 20
and the upper electrode film 80 and the wiring 29B are joined via the lead electrode
90, as shown in the figures, whereby a gap with an elastic film 50 when the reservoir
forming substrate 20 is bonded becomes only several µm and the piezoelectric elements
300 can be hermetically sealed in a piezoelectric element holding section 24 more
reliably, as described above.
[0081] Figs. 20A and 20B are a plan view and a sectional view of the main part of an ink
jet recording head according to a ninth embodiment of the invention.
[0082] In the ninth embodiment, as shown in Figs. 20A and 20B, a channel forming substrate
10 is formed with two rows of pressure generating chambers 12 placed side by side
in the width direction thereof so that the end parts of the pressure generating chambers
12 on the side of nozzle orifices 15 in one row are opposed to those in the other,
and a piezoelectric element 300 is formed in the area corresponding to each pressure
generating chamber 12. A reservoir 100 is provided for each row of the pressure generating
chambers 12 on the outside in the longitudinal direction of the pressure generating
chambers 12 and an ink introduction port 25 and an ink introduction passage 26 are
made to communicate with each reservoir 100. The structures of the reservoir, the
ink introduction port, etc. are similar to those in the above-described embodiments.
[0083] Each piezoelectric element 300 is extended from the area facing the corresponding
pressure generating chamber 12 to the top of the peripheral wall on the side of the
reservoir 100 and is sandwiched between the channel forming substrate 10 and a reservoir
forming substrate 20. As in the eighth embodiment, a through groove 35 is provided
for each row of the pressure generating chambers 12 on the side of a reservoir section
21 of the reservoir forming substrate 20, namely, in the area facing an upper electrode
film 80 of the piezoelectric element 300 in the area facing the peripheral wall of
the pressure generating chamber 12. For example, a drive circuit 130 for driving the
piezoelectric elements 300 is mounted on the reservoir forming substrate 20 in the
area corresponding to the space between the rows of the pressure generating chambers
12. The drive circuit 130 may be a circuit board or a semiconductor integrated circuit
(IC) containing the drive circuit. The upper electrode film 80 of each piezoelectric
element 300 and the drive circuit 130 are connected by wiring 29 extended by wire
bonding, etc., through the through groove 35. Further, wiring 29D for supplying a
signal to the drive circuit 130 is placed on the reservoir forming substrate 20 and
is connected at one end to the drive circuit 130 and an opposite end of the wiring
29D forms an installation section 120 to which external wiring 40 is connected.
[0084] According to the composition, the head can also be miniaturized as in the eighth
embodiment. Further, in the embodiment, the through groove 35 is made on the side
of the reservoir 100, so that piezoelectric elements 300, the drive circuit 130, and
the like can be connected more efficiently between the rows of the pressure generating
chambers 12.
[0085] In the embodiment, the drive circuit 130 is placed on the reservoir forming substrate
20, but the scope of the invention is not limited to it. For example, the wiring extended
from the piezoelectric element 300 and the external wiring such as a flexible cable
may be connected on an exposed portion 10a of the reservoir forming substrate 20 as
in the first embodiment, needless to say.
[0086] In the embodiment, the upper electrode films 80 of the piezoelectric elements 300
and the drive circuit 130 are connected by the wiring 29 extended only by wire bonding,
but the scope of the invention is not limited to it. For example, as shown in Fig.
21, an IC wiring section 140 made of a thin film may be placed in the area between
the drive circuit 130 on the reservoir forming substrate 20 and the through groove
35 and each piezoelectric element 300 and the drive circuit 130 may be connected via
the IC wiring section 140. That is, wiring 29E may be extended by wire bonding from
the upper electrode film 80 of each piezoelectric element 300 to one end part of the
IC wiring section 140 and the drive circuit 130 may be connected by wire bonding to
an opposite end part of the IC wiring section 140. The wiring 29E is extended by wire
bonding from the upper electrode film 80 to the IC wiring section 140, but the scope
of the invention is not limited to it. For example, as shown in Fig. 22, a conductive
thin film of gold (Au), etc., may be formed on the inner peripheral surface of the
through groove 35 and on the top of the reservoir forming substrate 20 and may be
patterned for each piezoelectric element 300, thereby providing the wiring 29E.
[0087] Figs. 23A and 23B are a plan view and a sectional view of the main part of an ink
jet recording head according to a tenth embodiment of the invention.
[0088] As shown in Figs. 23A and 23B, the tenth embodiment is an example wherein an installation
section 120 is placed in an exposed portion 10b on one end part side of a channel
forming substrate 10 in the direction in which piezoelectric elements 300 are placed
side by side.
[0089] That is, in the embodiment, each piezoelectric element 300 is placed in the area
facing each pressure generating chamber 12 and a lead electrode 90 is extended from
an upper electrode film 80 to the area facing a joint face 20c of a reservoir forming
substrate 20. Wiring 29F is placed on the joint face 20c of the reservoir forming
substrate 20 and an inner face 20e of a piezoelectric element holding section 24,
and the lead electrode 90 and the installation section 120 are connected. The tenth
embodiment is similar to the first embodiment in other points.
[0090] The route of the wiring 29F is not limited; when the reservoir forming substrate
20 is bonded with an adhesive, etc., the wiring 29F, the end part of each lead electrode
90, and one end of the installation section 120 may be connected.
[0091] In the composition, external wiring 40 can be drawn out from one end part in the
width direction of the pressure generating chamber 12, so that it is made possible
to arrange a plurality of recording heads horizontally. Of course, similar advantages
to those of the above-described embodiments can be provided.
[0092] The embodiments of the invention have been described, but the basic composition of
the ink jet recording head is not limited to the compositions described above.
[0093] For example, in the above-described embodiments, the reservoir forming substrate
20 having the reservoir section 21 forming a part of the reservoir 100 as the reservoir
forming member is joined to one side of the channel forming substrate 10, but the
scope of the invention is not limited to it. For example, the reservoir forming member
may adopt a structure wherein a plurality of substrates are used to form the reservoir.
[0094] Likewise, the nozzle plate 16 is joined as the reservoir forming member, but the
scope of the invention is not limited to it. For example, a multi-layer structure
containing another substrate having nozzle communication holes, etc., to allow nozzle
orifices and pressure generating chambers to communicate with each other may be adopted.
[0095] In the above-described embodiments, ink jet recording heads of thin film type that
can be manufactured by applying the film formation and lithography process are taken
as examples, but the scope of the invention is not limited to them. For example, the
invention can also be adopted for ink jet recording heads of thick film type formed
by a method of putting a green sheet or the like.
[0096] Each of the ink jet recording heads of the embodiments forms a part of a recording
head unit comprising an ink flow passage communicating with an ink cartridge, etc.,
and is installed in an ink jet recording apparatus. Fig. 24 is a schematic diagram
to show an example of the ink jet recording apparatus.
[0097] As shown in Fig. 24, cartridges 2A and 2B constituting an ink supply member are detachably
placed in recording head units 1A and 1B each having an ink jet recording head, and
a carriage 3 on which the recording head units 1A and 1B are mounted is placed axially
movably on a carriage shaft 5 attached to a recorder main body 4. The recording head
units 1A and 1B jet a black ink composite and a color ink composite respectively,
for example.
[0098] The driving force of a drive motor 6 is transmitted to the carriage 3 via a plurality
of gears (not shown) and a timing belt (not shown), whereby the carriage 3 on which
the recording head units 1A and 1B are mounted is moved along the carriage shaft 5.
On the other hand, the recorder main body 4 is provided with a platen 8 along the
carriage shaft 5. A recording sheet S of a recording medium such as paper fed by a
paper feed roller, etc., (not shown) is wrapped around the platen 8 and is transported.
[0099] As described above, according to the invention, the reservoir forming substrate forming
at least a part of the reservoir is joined onto the channel forming substrate for
forming the reservoir, thus the structure of the head can be simplified; the manufacturing
process can be decreased and the manufacturing costs can be reduced. Since the reservoir
forming substrate also serves as the capping member for insulating the piezoelectric
elements from the outside, the piezoelectric elements can be prevented from being
destroyed due to the external environment, and the durability can be improved. Further,
the piezoelectric elements and the external wiring are connected on the reservoir
forming substrate, whereby the head can be miniaturized.
1. An ink jet recording head comprising:
a nozzle forming member (16) provided with a plurality of nozzle orifices (15) for
jetting ink;
a channel forming substrate (10) provided with a plurality of pressure generating
chambers (12) communicated with the associated nozzle orifices (15), one face of which
is bonded to the nozzle forming member (16);
a plurality of piezoelectric elements (300) provided on a face of the channel forming
substrate (10) which is opposed to the face bonded to the nozzle forming substrate
(16) with a vibration plate (50) in between for changing the associated pressure generating
chambers (12) in volume thereof; and
a reservoir forming member (20) bonded to the face of the channel forming substrate
(10) on which the piezoelectric elements (300) are provided, the reservoir forming
member (20) having a reservoir section (21) forming at least a part of a reservoir
(100) communicated with the pressure generating chambers (12) for supplying ink thereto,
and a piezoelectric element holding section (24) for defining a space in an area facing
the piezoelectric elements (300) to such an extent that motion of the respective piezoelectric
elements (300) is exhibited while sealing the space hermetically, wherein the reservoir
section (21) is formed to extend across the pressure generating chambers (12).
2. The ink jet recording head according to claim 1, wherein the piezoelectric element
holding section (24) is partitioned by partition walls (27) so as to correspond to
the respective piezoelectric elements (300) and the partition walls (27) are bonded
to the channel forming substrate (10).
3. The ink jet recording head according to claim 1, wherein the channel forming substrate
(10) is formed with a communication section (13) for communicating with the reservoir
section (21) of the reservoir forming member (20) to form a part of the reservoir
(100) together with the reservoir section (21).
4. The ink jet recording head according to claim 1, wherein the reservoir (100) and each
pressure generating chamber (12) are made to communicate with each other via an ink
supply passage (14) relatively narrower than the reservoir (100).
5. The ink jet recording head according to claim 1, wherein an ink introduction port
(25) communicating with the outside for supplying ink to the reservoir (100) is made
to communicate with the reservoir section (21).
6. The ink jet recording head according to claim 1, wherein the reservoir section (21)
is so formed as to be across the pressure generating chambers (12) placed side by
side.
7. The ink jet recording head according to claim 1, wherein a part of the reservoir sections
(21) has a flexible section (22).
8. The ink jet recording head according to claim 7, wherein the channel forming substrate
(10) in the area corresponding to the reservoir section (21) is formed with a through
section (18) piercing the channel forming substrate (10) without communicating with
the pressure generating chambers (12), and wherein the flexible portion (22) is defined
as a section between the through section (18) and the reservoir section (21).
9. The ink jet recording head according to claim 8, wherein the through section (18)
is so formed as to be across the pressure generating chambers (12) placed side by
side.
10. The ink jet recording head according to claim 8, wherein the through section (18)
is etched together with the pressure generating chambers (12).
11. The ink jet recording head according to claim 7, wherein the flexible section (22)
is provided by bonding a flexible member.
12. The ink jet recording head according to claim 11, wherein the flexible member (22)
is a thin film (110) made of at least one of the metal and ceramic.
13. The ink jet recording head according to claim 11, wherein the flexible member (22)
is made of a resin material.
14. The ink jet recording head according to claim 13, wherein the resin material is at
least one selected from the group consisting of fluororesin, silicone resin and silicone
rubber.
15. The ink jet recording head according to claim 11, wherein the flexible member contains
a layer having a tensile stress.
16. The ink jet recording head according to claim 11, wherein the flexible member is composed
of a layer forming the piezoelectric elements (300).
17. The ink jet recording head according to claim 11, wherein another substrate having
a through hole (18) at least in an area facing the flexible section (22) is bonded
to the flexible member.
18. The ink jet recording head according to claim 11, wherein a projected beam member
(111) is provided on the surface of the flexible member on the opposite side to the
reservoir section (21) so as to extend in a plane direction of the flexible member.
19. The ink jet recording head according to claim 18, wherein the beam member (111) is
formed like a grid.
20. The ink jet recording head according to claim 11, wherein the reservoir section (21)
is provided with at least one beam-like reinforcing member (28) across side walls
defining the reservoir section (21) and facing each other.
21. The ink jet recording head according to claim 20, wherein at least a part of the reinforcing
member (28) is thinner than any other portion of the reservoir forming member (20).
22. The ink jet recording head according to claim 21, wherein at least a part (28a) of
the reinforcing member (28) on the side of the channel forming substrate (10) is removed
and is thinner than any other portion.
23. The ink jet recording head according to claim 20, wherein the reinforcing member (28)
is formed along the longitudinal direction of the piezoelectric elements (300).
24. The ink jet recording head according to claim 1, wherein at least a part of the area
of the reservoir forming member (20) facing the piezoelectric element (300) is formed
with a detection through hole (24a) for detecting displacement of the piezoelectric
element (300).
25. The ink jet recording head according to claim 24, wherein the piezoelectric element
holding section (24) is formed by piercing the reservoir forming member (20) and is
sealed with a transparent member, and also serves as the detection through hole (24a).
26. The ink jet recording head according to claim 25, wherein the transparent member forms
the flexible section (22c).
27. The inkjet recording head according to claim 1, further comprising:
a first wiring drawn out from the piezoelectric element on the channel forming substrate;
a second wiring provided on the reservoir forming member in an area opposite side
of the channel forming substrate;
a connection wiring for connecting the first and second wirings; and
an external wiring (40) connected to the second wiring.
28. The ink jet recording head according to claim 27, wherein the connection wiring is
formed by wire bonding.
29. The ink jet recording head according to claim 27, wherein the connection wiring is
formed of a thin film.
30. The ink jet recording head according to claim 27, wherein the reservoir forming member
(20) is formed with a communication hole piercing the reservoir forming member (20)
for communicating with the outside in the area corresponding to the piezoelectric
element (300), and
wherein the connection wiring is provided via the communication hole.
31. The ink jet recording head according to claim 30, wherein the communication hole is
provided in an area facing a peripheral wall of the pressure generating chamber (12)
on the reservoir side.
32. The ink jet recording head according to claim 30, wherein the communication hole is
provided in an area facing a peripheral wall of the pressure generating chamber (12)
on the nozzle orifice side.
33. The ink jet recording head according to claim 27, wherein a drive circuit for driving
the piezoelectric elements is mounted in the reservoir forming member and,
wherein the connection wiring is connected to the drive circuit.
34. The ink jet recording head according to claim 33, wherein the drive circuit is a semiconductor
integrated circuit.
35. The ink jet recording head according to claim 1, wherein the reservoir forming member
(20) is a reservoir forming substrate including the reservoir section (21).
36. The inkjet recording head according to claim 35, wherein the thermal expansion coefficient
of the reservoir forming substrate is substantially the same as that of the channel
forming substrate (10).
37. The ink jet recording head according to claim 35, wherein the reservoir forming substrate
is made of at least one material selected from the group consisting of silicon, glass
and ceramics.
38. The inkjet recording head according to claim 1, wherein the nozzle forming member
(16) is formed of substantially the same material as the channel forming substrate
(10) and the reservoir forming member (20).
39. The ink jet recording head according to claim 1, wherein the nozzle forming member
(16) is a nozzle plate provided with the nozzle orifices (15).
40. The ink jet recording head according to claim 1, wherein the pressure generating chambers
(12) are formed on a ceramic substrate, and
wherein the layers of the piezoelectric element (300) are formed by either putting
a green sheet or printing.
41. The ink jet recording head according to claim 1, wherein the pressure generating chambers
(12) are formed on a silicon monocrystalline substrate by anisotropic etching, and
wherein the layers of the piezoelectric element (300) are formed by thin film deposition
and lithography method.
42. The ink jet recording head according to claim 3, wherein cross-sectional shapes of
the reservoir section (21) and the communication section (13) are identical in directions
perpendicular to a laminating direction of the reservoir forming member (20) and the
channel forming substrate (10)
43. An ink jet recording apparatus comprising the ink jet recording head according to
any one of claims 1 to 42.
1. Tintenstrahlaufzeichnungskopf, der aufweist:
ein eine Düse bildendes Element (16), versehen mit einer Mehrzahl von Düsenöffnungen
(15) zum Ausstoßen von Tinte;
ein einen Kanal bildendes Substrat (10), versehen mit einer Mehrzahl von Druckerzeugungskammern
(12), die mit den zugeordneten Düsenöffnungen (15) in Verbindung gesetzt sind, wobei
eine Fläche davon an dem die Düse bildenden Element (16) angebondet ist;
eine Mehrzahl von piezoelektrischen Elementen (300), vorgesehen auf einer Fläche des
den Kanal bildenden Substrats (10), die zu der Fläche, angebondet an das die Düse
bildende Substrat (10), gegenüberliegt, mit einer Vibrationsplatte (50) dazwischen,
um die zugeordneten Druckerzeugungskammern (12) in deren Volumen zu ändern; und
ein ein Reservoir bildendes Element (20), angebondet an die Fläche des den Kanal bildenden
Substrats (10), auf dem die piezoelektrischen Elemente (300) vorgesehen sind, wobei
das das Reservoir bildende Element (20) einen Reservoirabschnitt (21) besitzt, der
mindestens einen Teil eines Reservoirs (100) bildet, das mit den Druckerzeugungskammern
(12) zum Zuführen von Tinte dazu in Verbindung gesetzt ist, und einen Halteabschnitt
(24) für ein piezoelektrisches Element zum Definieren eines Raums in einem Bereich,
der zu den piezoelektrischen Elementen (300) hinweist, in einem solchen Umfang, dass
eine Bewegung der jeweiligen piezoelektrischen Elemente (300) erzielt wird, während
der Raum hermetisch abgedichtet wird, wobei der Reservoirabschnitt (21) so ausgebildet
ist, um sich über die Druckerzeugungskammern (12) zu erstrecken, besitzt.
2. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei der Halteabschnitt (24) für das
piezoelektrische Element durch Trennwände (27) so unterteilt ist, um den jeweiligen,
piezoelektrischen Elementen (300) zu entsprechen, und wobei die Trennwände (27) an
dem den Kanal bildenden Substrat (10) angebondet sind.
3. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei das den Kanal bildende Substrat
(10) mit einem Verbindungsabschnitt (13) ausgebildet ist, um mit dem Reservoirabschnitt
(21) des das Reservoir bildenden Elements (20) in Verbindung zu stehen, um einen Teil
des Reservoirs (100) zusammen mit dem Reservoirabschnitt (21) zu bilden.
4. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei das Reservoir (100) und jede
Druckerzeugungskammer (12) so hergestellt sind, um miteinander über einen Tintenzuführkanal
(14), der relativ schmaler als das Reservoir (100) ist, in Verbindung zu stehen.
5. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei eine Tinteneinführöffnung (25),
die mit der Außenseite in Verbindung steht, um Tinte zu dem Reservoir (100) zuzuführen,
so aufgebaut ist, um mit dem Reservoirabschnitt (21) in Verbindung zu stehen.
6. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei der Reservoirabschnitt (21) so
gebildet ist, um die Druckerzeugungskammern (12), platziert Seite an Seite, zu überqueren.
7. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei ein Teil des Reservoirabschnitts
(21) einen flexiblen Abschnitt (22) besitzt.
8. Tintenstrahlaufzeichnungskopf nach Anspruch 7, wobei das den Kanal bildende Substrat
(10) in dem Bereich entsprechend zu dem Reservoirabschnitt (21) mit einem Duchgangsabschnitt
(18) ausgebildet ist, der das den Kanal bildende Substrat (10) durchdringt, ohne mit
den Druckerzeugungskammern (12) in Verbindung zu stehen, und wobei der flexible Bereich
(22) als ein Abschnitt zwischen dem Durchgangsabschnitt (18) und dem Reservoirabschnitt
(21) definiert ist.
9. Tintenstrahlaufzeichnungskopf nach Anspruch 8, wobei der Durchgangsabschnitt (18)
so ausgebildet ist, um die Druckerzeugungskammern (12), platziert Seite an Seite,
zu überqueren.
10. Tintenstrahlaufzeichnungskopf nach Anspruch 8, wobei der Durchgangsabschnitt (18)
zusammen mit den Druckerzeugungskammern (12) geätzt ist.
11. Tintenstrahlaufzeichnungskopf nach Anspruch 7, wobei der flexible Abschnitt (22) durch
Anbonden eines flexiblen Elements gebildet ist.
12. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei das flexible Element (22) ein
Dünnfilm (110), hergestellt aus zumindest einem von Metall und Keramik, ist.
13. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei das flexible Element (22) aus
einem Harzmaterial hergestellt ist.
14. Tintenstrahlaufzeichnungskopf nach Anspruch 13, wobei das Harzmaterial mindestens
eines ist, ausgewählt aus der Gruppe, die aus Fluoroharz, Silikonharz und Silikongummi
besteht.
15. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei das flexible Element eine Schicht
enthält, die eine Zugfestigkeit besitzt.
16. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei das flexible Element aus einer
Schicht aufgebaut ist, die die piezoelektrischen Elemente (300) bildet.
17. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei ein anderes Substrat, das ein
Durchgangsloch (18) zumindest in einem Bereich, der zu dem flexiblen Abschnitt (22)
hinweist, besitzt, an dem flexiblen Element angebondet ist.
18. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei ein vorstehendes Stabelement
(111) auf der Oberfläche des flexiblen Elements auf der gegenüberliegenden Seite zu
dem Reservoirabschnitt (21) vorgesehen ist, um sich so in einer ebenen Richtung des
flexiblen Elements zu erstrecken.
19. Tintenstrahlaufzeichnungskopf nach Anspruch 18, wobei das Stabelement (111) ähnlich
eines Gitters ausgebildet ist.
20. Tintenstrahlaufzeichnungskopf nach Anspruch 11, wobei der Reservoirabschnitt (21)
mit mindestens einem stabähnlichen Verstärkungselement (28) über Seitenwände, die
den Reservoirabschnitt (21) definieren und zueinander hinweisend, versehen ist.
21. Tintenstrahlaufzeichnungskopf nach Anspruch 20, wobei mindestens ein Teil des Verstärkungselements
(28) dünner als irgendein anderer Bereich des das Reservoir bildenden Elements (20)
ist.
22. Tintenstrahlaufzeichnungskopf nach Anspruch 21, wobei mindestens ein Teil (28a) des
Verstärkungselements (28) auf der Seite des den Kanal bildenden Substrats (10) entfernt
ist und dünner als irgendein anderer Bereich ist.
23. Tintenstrahlaufzeichnungskopf nach Anspruch 20, wobei das Verstärkungselement (28)
entlang der Längsrichtung der piezoelektrischen Elemente (300) ausgebildet ist.
24. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei mindestens ein Teil des Bereichs
des das Reservoir bildenden Elements (20), der zu dem piezoelektrischen Element (300)
hinweist, mit einem Erfassungsdurchgangsloch (24a) zum Erfassen einer Verschiebung
des piezoelektrischen Elements (300) ausgebildet ist.
25. Tintenstrahlaufzeichnungskopf nach Anspruch 24, wobei der Halteabschnitt (24) für
das piezoelektrische Element durch Durchdringen des das Reservoir bildenden Elements
(20) gebildet ist und mit einem transparenten Element abgedichtet ist, und auch als
das Erfassungsdurchgangsloch (24a) dient.
26. Tintenstrahlaufzeichnungskopf nach Anspruch 25, wobei das transparente Element den
flexiblen Abschnitt (22c) bildet.
27. Tintenstrahlaufzeichnungskopf nach Anspruch 1, der weiterhin aufweist:
eine erste Verdrahtung, die von dem piezoelektrischen Element auf dem den Kanal bildenden
Substrat herausgezogen ist;
eine zweite Verdrahtung, vorgesehen auf dem das Reservoir bildenden Element in einem
Bereich einer gegenüberliegenden Seite des den Kanal bildenden Substrats;
eine Verbindungsverdrahtung zum Verbinden der ersten und der zweiten Verdrahtung;
und
eine externe Verdrahtung (40), verbunden mit der zweiten Verdrahtung.
28. Tintenstrahlaufzeichnungskopf nach Anspruch 27, wobei die Verbindungsverdrahtung durch
Drahtbonden gebildet ist.
29. Tintenstrahlaufzeichnungskopf nach Anspruch 27, wobei die Verbindungsverdrahtung aus
einem Dünnfilm gebildet ist.
30. Tintenstrahlaufzeichnungskopf nach Anspruch 27, wobei das das Reservoir bildende Element
(20) mit einem Verbindungsloch ausgebildet ist, das das Reservoir bildende Element
(20) durchdringt, um mit der Außenseite in dem Bereich entsprechend zu dem piezoelektrischen
Element (300) in Verbindung zu treten, und
wobei die Verbindungsverdrahtung über das Verbindungsloch vorgesehen ist.
31. Tintenstrahlaufzeichnungskopf nach Anspruch 30, wobei das Verbindungsloch in einem
Bereich vorgesehen ist, der zu einer Umfangswand der Druckerzeugungskammer (12) auf
der Seite des Reservoirs hinweist.
32. Tintenstrahlaufzeichnungskopf nach Anspruch 30, wobei das Verbindungsloch in einem
Bereich vorgesehen ist, der zu einer Umfangswand der Druckerzeugungskammer (12) auf
der Seite der Düsenöffnung hinweist.
33. Tintenstrahlaufzeichnungskopf nach Anspruch 27, wobei eine Ansteuerschaltung zum Ansteuern
der piezoelektrischen Elemente in dem das Reservoir bildenden Element befestigt ist,
und
wobei die Verbindungsverdrahtung mit der Ansteuerschaltung verbunden ist.
34. Tintenstrahlaufzeichnungskopf nach Anspruch 33, wobei die Ansteuerschaltung eine integrierte
Halbleiterschaltung ist.
35. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei das das Reservoir bildende Element
(20) ein ein Reservoir bildendes Substrat, umfassend den Reservoirabschnitt (21),
ist.
36. Tintenstrahlaufzeichnungskopf nach Anspruch 35, wobei der thermische Expansionskoeffizient
des das Reservoir bildenden Substrats im Wesentlichen derselbe wie derjenige des den
Kanal bildenden Substrats (10) ist.
37. Tintenstrahlaufzeichnungskopf nach Anspruch 35, wobei das das Reservoir bildende Substrat
aus mindestens einem Material hergestellt ist, das aus der Gruppe ausgewählt ist,
die aus Silizium, Glas und Keramiken besteht.
38. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei das die Düse bildende Element
(16) aus im Wesentlichen demselben Material wie das den Kanal bildende Substrat (10)
und das das Reservoir bildende Element (20) gebildet ist.
39. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei das die Düse bildende Element
(16) eine Düsenplatte, versehen mit den Düsenöffnungen (15), ist.
40. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei die Druckerzeugungskammern (12)
auf einem keramischen Substrat gebildet sind, und
wobei die Schichten des piezoelektrischen Elements (300) durch entweder Heranziehen
einer grünen Platte oder durch Drucken gebildet sind.
41. Tintenstrahlaufzeichnungskopf nach Anspruch 1, wobei die Druckerzeugungskammern (12)
auf einem monokristallinen Siliziumsubstrat durch anisotropes Ätzen gebildet sind,
und
wobei die Schichten des piezoelektrischen Elements (300) durch ein Dünnfilm-Niederschlags-
und Lithografieverfahren gebildet sind.
42. Tintenstrahlaufzeichnungskopf nach Anspruch 3, wobei die Querschnittsformen des Reservoirabschnitts
(21) und des Verbindungsabschnitts (13) in Richtungen senkrecht zu einer Laminierrichtung
des das Reservoir bildenden Elements (20) und des den Kanal bildenden Substrats (10)
identisch sind.
43. Tintenstrahlaufzeichnungsgerät, das den Tintenstrahlaufzeichnungskopf nach einem der
Ansprüche 1 bis 42 aufweist.
1. Tête d'enregistrement à jet d'encre comprenant :
un élément formant buse (16) pourvu d'une pluralité d'orifices de buse (15) pour éjecter
de l'encre ;
un substrat formant canal (10) pourvu d'une pluralité de chambres de génération de
pression (12) qui communiquent avec les orifices de buse (15) associés, dont une face
est liée à l'élément formant buse (16) ;
une pluralité d'éléments piézoélectriques (300) prévus sur une face du substrat formant
canal (10) qui est opposée à la face liée au substrat formant buse (16), une plaque
de vibration (50) étant présente entre eux pour modifier le volume des chambres de
génération de pression (12) associées ; et
un élément formant réservoir (20) lié à la face du .substrat formant canal (10) sur
laquelle les éléments piézoélectriques (300) sont prévus, l'élément formant réservoir
(20) comportant une section de réservoir (21) faisant au moins partie d'un réservoir
(100) qui communique avec les chambres de génération de pression (12) pour fournir
de l'encre à celles-ci et une section de maintien d'éléments piézoélectriques (24)
pour définir un espace dans une région faisant face aux éléments piézoélectriques
(300) dans une mesure telle qu'un mouvement des éléments piézoélectriques (300) respectifs
soit effectué tout en fermant l'espace hermétiquement, dans laquelle la section de
réservoir (21) est formée pour s'étendre transversalement aux chambres de génération
de pression (12).
2. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle la section
de maintien d'éléments piézoélectriques (24) est divisée par des parois de séparation
(27) de manière à correspondre aux éléments piézoélectriques (300) respectifs et les
parois de séparation (27) sont liées au substrat formant canal (10).
3. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle le substrat
formant canal (10) est formé d'une section de communication (13) pour communiquer
avec la section de réservoir (21) de l'élément formant réservoir (20) afin de former
une partie du réservoir (100) avec la section de réservoir (21).
4. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle le réservoir
(100) et chaque chambre de génération de pression (12) sont amenés à communiquer l'un
avec l'autre par l'intermédiaire d'un passage d'alimentation en encre (14) relativement
plus étroit que le réservoir (100).
5. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle un orifice
d'introduction d'encre (25) communiquant avec l'extérieur pour fournir de l'encre
au réservoir (100) est amené à communiquer avec la section de réservoir (21).
6. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle la section
de réservoir (21) est formée de manière à être transversale aux chambres de génération
de pression (12) placées côte à côte.
7. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle une partie
de la section de réservoir (21) comporte une section flexible (22).
8. Tête d'enregistrement à jet d'encre selon la revendication 7, dans laquelle le substrat
formant canal (10) dans la région correspondant à la section de réservoir (21) est
formé d'une section traversante (18) perçant le substrat formant canal (10) sans communiquer
avec les chambres de génération de pression (12), et dans laquelle la partie flexible
(22) est définie en tant que section entre la section traversante (18) et la section
de réservoir (21).
9. Tête d'enregistrement à jet d'encre selon la revendication 8, dans laquelle la section
traversante (18) est formée de manière à être transversale aux chambres de génération
de pression (12) placées côte à côte.
10. Tête d'enregistrement à jet d'encre selon la revendication 8, dans laquelle la section
traversante (18) est gravée en même temps que les chambres de génération de pression
(12).
11. Tête d'enregistrement à jet d'encre selon la revendication 7, dans laquelle la section
flexible (22) est réalisée en collant un élément flexible.
12. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle l'élément
flexible (22) est un film mince (110) réalisé en au moins l'un du métal et de la céramique.
13. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle l'élément
flexible (22) est réalisé en une résine.
14. Tête d'enregistrement à jet d'encre selon la revendication 13, dans laquelle la résine
est au moins l'un sélectionné dans le groupe consistant en une résine fluorée, une
résine de silicone et un caoutchouc de silicone.
15. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle l'élément
flexible contient une couche ayant une certaine contrainte de tension.
16. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle l'élément
flexible est composé d'une couche formant les éléments piézoélectriques (300).
17. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle un autre
substrat comportant un trou traversant (18) au moins dans une région faisant face
à la section flexible (22) est collé à l'élément flexible.
18. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle un élément
profilé saillant (111) est prévu sur la surface de l'élément flexible du côté opposé
à la section de réservoir (21) de manière à s'étendre dans une direction plane de
l'élément flexible.
19. Tête d'enregistrement à jet d'encre selon la revendication 18, dans laquelle l'élément
profilé (111) est formé comme une grille.
20. Tête d'enregistrement à jet d'encre selon la revendication 11, dans laquelle la section
de réservoir (21) est pourvue d'au moins un élément de renforcement semblable à un
profilé (28) transversal aux parois latérales définissant la section de réservoir
(21) et se faisant face.
21. Tête d'enregistrement à jet d'encre selon la revendication 20, dans laquelle au moins
une partie de l'élément de renforcement (28) est plus mince que n'importe quelle autre
partie de l'élément formant réservoir (20).
22. Tête d'enregistrement à jet d'encre selon la revendication 21, dans laquelle au moins
une partie (28a) de l'élément de renforcement (28) du côté du substrat formant canal
(10) est retirée et la partie restante est plus mince que n'importe quelle autre partie.
23. Tête d'enregistrement à jet d'encre selon la revendication 20, dans laquelle l'élément
de renforcement (28) est formé dans la direction longitudinale des éléments piézoélectriques
(300).
24. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle au moins
une partie de la région de l'élément formant réservoir (20) faisant face à l'élément
piézoélectrique (300) est formée d'un trou traversant de détection (24a) pour détecter
un déplacement de l'élément piézoélectrique (300).
25. Tête d'enregistrement à jet d'encre selon la revendication 24, dans laquelle la section
de maintien d'éléments piézoélectriques (24) est formée en perçant l'élément formant
réservoir (20) et est fermée hermétiquement par un élément transparent, et sert également
en tant que trou traversant de détection (24a).
26. Tête d'enregistrement à jet d'encre selon la revendication 25 , dans laquelle l'élément
transparent forme la section flexible (22c).
27. Tête d'enregistrement à jet d'encre selon la revendication 1, comprenant en outre
:
un premier câblage s'étendant à partir de l'élément piézoélectrique sur le substrat
formant canal ;
un deuxième câblage prévu sur l'élément formant réservoir dans une région du côté
opposé au substrat formant canal ;
un câblage de connexion pour connecter les premier et deuxième câblages ; et
un câblage externe (40) connecté au deuxième câblage.
28. Tête d'enregistrement à jet d'encre selon la revendication 27, dans laquelle le câblage
de connexion est formé par liaison par fils.
29. Tête d'enregistrement à jet d'encre selon la revendication 27, dans laquelle le câblage
de connexion est réalisé par un film mince.
30. Tête d'enregistrement à jet d'encre selon la revendication 27, dans laquelle l'élément
formant réservoir (20) est formé d'un trou de communication perçant l'élément formant
réservoir (20) pour communiquer avec l'extérieur dans la région correspondant à l'élément
piézoélectrique (300), et
dans laquelle le câblage de connexion est réalisé par l'intermédiaire du trou de
communication.
31. Tête d'enregistrement à jet d'encre selon la revendication 30, dans laquelle le trou
de communication est prévu dans une région faisant face à une paroi périphérique de
la chambre de génération de pression (12) du côté du réservoir.
32. Tête d'enregistrement à jet d'encre selon la revendication 30, dans laquelle le trou
de communication est prévu dans une région faisant face à une paroi périphérique de
la chambre de génération de pression (12) du côté des orifices de buse.
33. Tête d'enregistrement à jet d'encre selon la revendication 27, dans laquelle un circuit
de commande pour commander les éléments piézoélectriques est monté dans l'élément
formant réservoir et,
dans laquelle le câblage de connexion est connecté au circuit de commande.
34. Tête d'enregistrement à jet d'encre selon la revendication 33, dans laquelle le circuit
de commande est un circuit intégré à semi-conducteurs.
35. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle l'élément
formant réservoir (20) est un substrat formant réservoir comprenant la section de
réservoir (21).
36. Tête d'enregistrement à jet d'encre selon la revendication 35, dans laquelle le coefficient
de dilatation thermique du substrat formant réservoir est sensiblement identique à
celui du substrat formant canal (10).
37. Tête d'enregistrement à jet d'encre selon la revendication 35, dans laquelle le substrat
formant réservoir est réalisé en au moins un matériau sélectionné dans le groupe consistant
en du silicium, du verre et des céramiques.
38. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle l'élément
formant buse (16) est réalisé sensiblement en le même matériau que le substrat formant
canal (10) et l'élément formant réservoir (20).
39. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle l'élément
formant buse (16) est une plaque de buse pourvue des orifices de buse (15).
40. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle les chambres
de génération de pression (12) sont formées sur un substrat en céramique, et
dans laquelle les couches de l'élément piézoélectrique (300) sont formées soit
en plaçant une feuille verte, soit par impression.
41. Tête d'enregistrement à jet d'encre selon la revendication 1, dans laquelle les chambres
de génération de pression (12) sont formées sur un substrat en silicium monocristallin
par gravure anisotrope, et
dans laquelle les couches de l'élément piézoélectrique (300) sont formées par dépôt
de couches minces et par un procédé lithographique.
42. Tête d'enregistrement à jet d'encre selon la revendication 3, dans laquelle les formes
en coupe de la section de réservoir (21) et de la section de communication (13) sont
identiques dans des directions perpendiculaires à une direction de stratification
de l'élément formant réservoir (20) et du substrat formant canal (10).
43. Dispositif d'enregistrement à jet d'encre comprenant la tête d'enregistrement à jet
d'encre selon l'une quelconque des revendications 1 à 42.