U.S. patent application number 15/132500 was filed with the patent office on 2016-08-11 for liquid ejecting head unit and liquid ejecting apparatus.
The applicant listed for this patent is Seiko Epson Corporation. Invention is credited to Takahiro KANEGAE.
Application Number | 20160229181 15/132500 |
Document ID | / |
Family ID | 52110571 |
Filed Date | 2016-08-11 |
United States Patent
Application |
20160229181 |
Kind Code |
A1 |
KANEGAE; Takahiro |
August 11, 2016 |
LIQUID EJECTING HEAD UNIT AND LIQUID EJECTING APPARATUS
Abstract
A head unit includes a head, an upstream member with an upstream
passage supplied with liquid, a downstream member with a downstream
passage communicating with the upstream passage and supplying
liquid to the head, an elastic sealer connecting the upstream and
downstream passages, and including a tube with a connection
passage, and a support between the sealer and the downstream
member. In the head unit, the upstream member and the sealer apply
pressure in a penetration direction of the connection passage and
hermetically seal the upstream passage, the sealer and the
downstream member apply pressure in a direction perpendicular to
the penetration direction of the tube and hermetically seal the
downstream passage, and the support abuts a region on a surface of
the sealer, the surface being opposite the upstream member, the
region overlapping a region to which the sealer and the upstream
member apply pressure.
Inventors: |
KANEGAE; Takahiro;
(Shiojiri, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Seiko Epson Corporation |
Tokyo |
|
JP |
|
|
Family ID: |
52110571 |
Appl. No.: |
15/132500 |
Filed: |
April 19, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14302911 |
Jun 12, 2014 |
9340020 |
|
|
15132500 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B41J 2/1433 20130101;
F16J 15/06 20130101; B41J 2/14 20130101; B41J 2002/14362 20130101;
B41J 2/175 20130101; B41J 2002/14403 20130101 |
International
Class: |
B41J 2/14 20060101
B41J002/14; F16J 15/06 20060101 F16J015/06; B41J 2/175 20060101
B41J002/175 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 20, 2013 |
JP |
2013-129336 |
Claims
1. A sealing member comprising: a tubular portion having a
connection passage thereinside; a first end surface of one end of
the tubular portion, defining a first hole connecting to the
connection passage; and a second end surface of the other end of
the tubular portion, defining a second hole connecting to the
connection passage, wherein the first end surface is for abutting
against a first passage member to hermetically seal the first hole
and a passage of the first passage member, the second end surface
is for receiving a second passage member into the second hole to
hermetically seal the connection passage and a passage of the
second passage member.
2. The sealing member according to claim 1, wherein an inner
surface of the connection passage is configured to come into
intimate contact with an outer circumferential surface of a part of
the second passage member which is provided with the passage
thereinside.
3. The sealing member according to claim 1, wherein in diameter the
first hole is substantially equal to an opening of the first
passage member which connects the first hole.
4. The sealing member according to claim 1, wherein the first
passage member and the sealing member apply pressure in a
penetration direction of the connection passage.
5. The sealing member according to claim 1, wherein the sealing
member and the second passage member apply pressure in a direction
perpendicular to a penetration direction of the connection
passage.
6. The sealing member according to claim 1, wherein the first
passage member comprises a filter intersecting the passage
thereof.
7. The sealing member according to claim 1, wherein the second
passage member comprises projecting portion provided with the
passage thereinside and to be inserted into the second hole toward
the first hole of the sealing member.
8. The sealing member according to claim 7, wherein the tuber
portion keeps the projecting portion from projecting out of the
first hole.
9. A liquid ejecting apparatus comprising: a sealing member
according to claim 1; a first passage member abutting against the
first end surface of the sealing member; and a second passage
member inserted into the connection passage of the sealing
member.
10. The sealing member according to claim 8, wherein an inner
surface of the connection passage is configured to come into
intimate contact with an outer circumferential surface of a part of
the second passage member which is provided with the passage
thereinside.
11. The sealing member according to claim 8, wherein in diameter
the first hole is substantially equal to an opening of the first
passage member which connects the first hole.
12. The sealing member according to claim 8, wherein the first
passage member and the sealing member apply pressure in a
penetration direction of the connection passage.
13. The sealing member according to claim 8, wherein the sealing
member and the second passage member apply pressure in a direction
perpendicular to a penetration direction of the connection
passage.
14. The sealing member according to claim 8, wherein the first
passage member comprises a filter intersecting the passage
thereof.
15. A liquid ejecting apparatus comprising: a sealing member
according to claim 8; a first passage member abutting against the
first end surface of the sealing member; and a second passage
member inserted into the connection passage of the sealing member.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation patent application of U.S.
application Ser. No. 14/302,911, filed Jun. 12, 2014, which claims
priority to Japanese Patent Application No. 2013-129336, filed Jun.
20, 2013, both applications are expressly incorporated by reference
herein in their entireties.
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates to a liquid ejecting head unit
that ejects liquid from a nozzle and a liquid ejecting apparatus,
and particularly relates to an ink jet recording head unit that
discharges ink as liquid and an ink jet recording apparatus.
[0004] 2. Related Art
[0005] Representative examples of a liquid ejecting head unit that
ejects liquid include an ink jet recording head unit that
discharges drops of ink. For example, JP-A-2009-6730 proposes an
ink jet recording head unit that includes an ink jet recording
head, which discharges drops of ink from a nozzle, and a passage
member, which is fixed to the ink jet recording head and supplies
ink from a liquid reservoir in which the ink is stored, such as an
ink cartridge, to a liquid ejecting head.
[0006] The passage member of the ink jet recording head unit
includes an upstream passage member, to which the ink is supplied
from the liquid reservoir, and a downstream passage member, which
holds the ink jet recording head and supplies the ink from the
upstream passage member to the ink jet recording head. The passage
member performs hermetic sealing so as to prevent the ink from
leaking from a connection passage by causing a sealing member made
of a plate-like elastic material, such as a sheet, to be pinched
between the upstream passage member and the downstream passage
member.
[0007] However, when it is attempted to hermetically seal the
passage in which the upstream passage member and the downstream
passage member are connected using the sealing member pinched
between two members and made of an elastic material, such as a
rubber sheet, repulsion based on elastic deformation of the sealing
member may cause pressure to be applied in a direction in which the
upstream passage member and the downstream passage member are
separated from each other, and pressure may be applied in a
direction perpendicular to a liquid ejecting surface that
discharges the drops of ink of the liquid ejecting head. As a
result, a malfunction may occur, such as separation of the passage
member and the liquid ejecting head, separation of a layer member
that is a constituent of the liquid ejecting head, or deviation
from positions at which the drops of ink are expected to be
supplied on an ejected medium, which is caused by warping of the
liquid ejecting surface of the liquid ejecting head.
[0008] In contrast, JP-A-2003-305873 proposes a structure in which
two passages are connected through a tube. Although the connection
of two passages through a tube may reduce pressure in a direction
perpendicular to a liquid ejecting surface, it is necessary to fit
the tube to both an upper passage and a lower passage and
assembling may be complicated.
[0009] Besides, in both cases in which the plate-like sealing
member is used and the tube-like sealing member is used, it is
necessary to press the upstream passage member relatively against
the downstream passage member in assembling the upstream passage
member and the downstream passage member, and the pressing may
cause pressure to be applied in the direction in which the upstream
passage member and the downstream passage member are separated from
each other.
[0010] Similar to the ink jet recording head unit, the liquid
ejecting head unit that ejects liquid other than ink also has such
possibilities.
[0011] An advantage of some aspects of the invention is to propose
a liquid ejecting head unit and a liquid ejecting apparatus, which
enable passages to be connected preferably and improve
assembility.
SUMMARY
[0012] According to a first aspect of the invention, a liquid
ejecting head unit includes a liquid ejecting head that drives a
pressure generator and discharges liquid from a nozzle, an upstream
passage member with an upstream passage to which liquid is supplied
from a liquid retaining portion that retains liquid, a downstream
passage member with a downstream passage that communicates with the
upstream passage of the upstream passage member and supplies liquid
to the liquid ejecting head, a sealing member that connects the
upstream passage of the upstream passage member and the downstream
passage of the downstream passage member, includes a tubular
portion provided inside with a connection passage through which
liquid flows, and is made of an elastic material, and a support
portion provided between the sealing member and the downstream
passage member. In the liquid ejecting head unit, the upstream
passage member and the sealing member apply pressure in a
penetration direction of the connection passage of the tubular
portion and hermetically seal the upstream passage, the sealing
member and the downstream passage member apply pressure in a
direction perpendicular to the penetration direction of the tubular
portion and hermetically seal the downstream passage, and the
support portion abuts a region on a side of a surface of the
sealing member, the surface being opposite the upstream passage
member, the region overlapping a region to which the sealing member
and the upstream passage member apply pressure.
[0013] According to the first aspect, since pressure is applied in
the penetration direction of a connection passage due to the
hermetic sealing of the upstream passage member and the sealing
member, which involves no fitted connection, positioning may easily
be performed and assembility may be improved. In addition, since
the pressure in the penetration direction may be supported by the
support portion, it is possible to suppress application of the
pressure in the penetration direction to the liquid ejecting head.
Further, since the downstream passage member and the sealing member
are hermetically sealed in the direction perpendicular to the
penetration direction, it is possible to suppress application of
pressure in the penetration direction.
[0014] According to a second aspect of the invention, a liquid
ejecting apparatus includes the liquid ejecting head unit according
to the first aspect of the invention.
[0015] According to the second aspect, it is possible to implement
a liquid ejecting apparatus that enables passages to be connected
preferably and improves assembility.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention will be described with reference to the
accompanying drawings, wherein like numbers reference like
elements.
[0017] FIG. 1 is an exploded perspective view of a head unit
according to a first embodiment of the invention;
[0018] FIG. 2 is a cross-sectional view of the head unit according
to the first embodiment of the invention;
[0019] FIG. 3 is a cross-sectional view in which a main part of the
head unit according to the first embodiment of the invention is
enlarged; and
[0020] FIG. 4 is a perspective view that illustrates a schematic
structure of a recording apparatus according to an embodiment of
the invention.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0021] The invention is described in detail below based on
embodiments.
First Embodiment
[0022] FIG. 1 is an exploded perspective view of an ink jet
recording head unit, which is an example of a liquid ejecting head
unit according to a first embodiment of the invention.
[0023] FIG. 2 is a cross-sectional view of the ink jet recording
head unit. FIG. 3 is a cross-sectional view in which a main part of
FIG. 2 is enlarged.
[0024] As illustrated, an ink jet recording head unit 1, which is
hereinafter also referred to merely as the head unit 1 and is an
example of the liquid ejecting head unit according to the present
embodiment, includes a plurality of ink jet recording heads 10,
which are hereinafter also referred to merely as the recording
heads 10 and discharge drops of ink from nozzles, and a passage
member 20, which holds the plurality of recording heads 10 and is
provided with a liquid passage that supplies liquid to the
recording heads 10.
[0025] The recording head 10 includes a liquid ejecting surface 12
on one side, through which the nozzles that discharges drops of ink
as liquid are opened. The liquid ejecting surface 12 of the present
embodiment is provided with two nozzle rows that are not
particularly illustrated but are arranged in a direction that
crosses the direction in which the nozzles are arranged side by
side. In the present embodiment, the direction in which the nozzles
are arranged side by side in each nozzle row is referred to as a
first direction X, and the direction in which the nozzle rows are
formed so as to cross the first direction X is referred to as a
second direction Y.
[0026] The inside of the recording head 10, which is not
illustrated, is provided with a passage that communicates with the
nozzles and communicates with the liquid passage of the passage
member 20, a pressure generating portion that causes change in
pressure for the ink in the passage, and the like. Examples of the
pressure generating portion that is usable include a unit that
causes drops of ink to be discharged from nozzles by changing the
capacity of a passage using deformation of a piezoelectric actuator
that contains a piezoelectric material with an electromechanical
transduction function and bringing a change in pressure to the ink
in the passage, a unit that causes drops of ink to be discharged
from nozzles by arranging a heating element in a passage and using
bubbles caused by the heat from the heating element, and a
so-called electrostatic actuator, which causes drops of ink to be
discharged from nozzles by generating electrostatic force between a
vibrating plate and an electrode and deforming the vibrating plate
using the electrostatic force.
[0027] A surface of the recording head 10 opposite the liquid
ejecting surface 12 is fixed to the passage member 20, and the ink
held in a liquid retaining portion, such as an ink cartridge or an
ink tank, is supplied through the passage member 20. The passage
member 20 is provided with the plurality of recording heads 10. In
the present embodiment, the passage member 20 is provided with two
rows of the recording heads 10 arranged in the first direction X
and in each of the two rows, six of the recording heads 10 are
arranged side by side in the second direction Y in which the nozzle
rows are formed. That is, a total of 12 nozzle rows are arranged in
parallel in the second direction Y in one head unit (the head unit
1). Further, in the present embodiment, a direction in which the
passage member 20 and the recording heads 10 are fixed is referred
to as a third direction Z. That is, the direction in which the
passage member 20 and the recording heads 10 are fixed indicates
the layer direction and also indicates the direction perpendicular
to the plane direction of the liquid ejecting surface 12, which is
an in-plane direction of the first direction X and the second
direction Y.
[0028] The method of fixing the recording heads 10 and the passage
member 20 is not particularly limited. For example, the recording
heads 10 and the passage member 20 may be bonded by a bonding agent
or fixed with screws or the like. Since the recording head 10 is
small in size and it is necessary to attach the plurality of
recording heads 10 to one passage member, which is the passage
member 20, use of a sealing member made of an elastic material is
unsuitable for fixing the recording heads 10 and the passage member
20. Accordingly, it is preferable to bond the recording heads 10
and the passage member 20 using a bonding agent.
[0029] The passage member 20 to which the recording heads 10 are
fixed includes an upstream passage member 30 provided with an
upstream passage 101 to which the liquid retaining portion is
connected, a downstream passage member 40 provided with a
downstream passage 102 that communicates with the upstream passage
101, and a sealing member 50 that is provided between the upstream
passage member 30 and the downstream passage member 40 and
hermetically seals the connection portion of the upstream passage
101 and the downstream passage 102, and a support member 60
provided with a support portion 61 that supports the sealing member
50. That is, the liquid passage of the passage member 20 includes
the upstream passage 101 and the downstream passage 102.
[0030] In the present embodiment, a first upstream passage member
31, a second upstream passage member 32, and a third upstream
passage member 33 are provided so as to form layers in the third
direction Z and make up the upstream passage member 30. The
upstream passage member 30 is not particularly limited to this
structure but may be a single member or may be made up of two or
more members. The layer direction of the plurality of members that
make up the upstream passage member is not particularly limited,
either, but may be in the first direction X or the second direction
Y.
[0031] The first upstream passage member 31 is provided with a
connection portion 34 on the side of a surface opposite the
downstream passage member 40, and the connection portion 34 is
connected to the liquid retaining portion in which the ink (liquid)
is held. In the present embodiment, the connection portion 34
projects like a needle, which is connected to the liquid retaining
portion. The liquid retaining portion, such as an ink cartridge,
may be directly connected to the connection portion 34, or the
liquid retaining portion, such as an ink tank, may be connected to
the connection portion 34 through a supply pipe, such as a tube.
The inside of the connection portion 34 is provided with a first
upstream passage 101a through which the ink is supplied from the
liquid retaining portion. The downstream side of the first upstream
passage 101a is provided with a liquid accumulation portion 101b
with an inner diameter that is largely widened compared to the
first upstream passage 101a in the connection portion 34.
[0032] The second upstream passage member 32 is fixed on the side
of a surface of the first upstream passage member 31, which is
opposite the connection portion 34, and includes a second upstream
passage 101c that communicates with the first upstream passage
101a. An opening portion of the second upstream passage 101c of the
second upstream passage member 32 is provided with a filter 35 for
removing an air bubble or a foreign substance contained in the ink,
and the ink supplied from the first upstream passage 101a (the
liquid accumulation portion 101b) is supplied to the second
upstream passage 101c through the filter 35. Depending on the
positions of the first upstream passage 101a and a third upstream
passage 101d, which is described below, the second upstream passage
101c may be any one of a passage that extends in the third
direction Z in which the first upstream passage member 31 and the
second upstream passage member 32 form layers, a passage that
extends in the direction perpendicular to the third direction Z,
that is, a passage that extends in a plane including the first
direction X and the second direction Y, and the like.
[0033] The third upstream passage member 33 is provided on a side
of the second upstream passage member 32, which is opposite the
first upstream passage member 31. The third upstream passage member
33 is provided with the third upstream passage 101d that
communicates with the second upstream passage 101c of the second
upstream passage member 32. That is, the upstream passage 101
includes the first upstream passage 101a, (the liquid accumulation
portion 101b,) the second upstream passage 101c, and the third
upstream passage 101d. The third upstream passage 101d is opened at
one end on the side of the second upstream passage member 32 and
communicates with the second upstream passage 101c. Further, the
third upstream passage 101d is provided so as to be opened at the
other end on the side of the downstream passage member 40. The
cross section of the upstream passage 101 is not limited to a
circular shape but may be an elliptic shape, a rectangular shape,
or the like.
[0034] For example, the first upstream passage member 31, the
second upstream passage member 32, and the third upstream passage
member 33, which include the upstream passage 101, are integrally
arranged in layers using a bonding agent, by welding, or the like.
Although the first upstream passage member 31, the second upstream
passage member 32, and the third upstream passage member 33 may be
fixed with screws, clamps, or the like, it is preferable to join
the first upstream passage member 31, the second upstream passage
member 32, and the third upstream passage member 33 with a bonding
agent, by welding, or the like so as to suppress leakage of the ink
(liquid) from the connection portion from the first upstream
passage 101a to the third upstream passage 101d.
[0035] The third upstream passage member 33 is further provided
with a depressed portion 37 that is opened on the side of the
downstream passage member 40. A bottom surface of the depressed
portion 37, that is, the surface on the side of the first upstream
passage member 31 is provided with a fixing hole 38 that penetrates
in the thickness direction. When a fixing portion 66 provided to
the support member 60, which is described in detail below, so as to
project on the side of the upstream passage member 30 is inserted
into the depressed portion 37 and a fixing screw 39 is inserted
into the fixing hole 38 so as to be threadedly engaged with the
fixing portion 66, the upstream passage member 30 is fixed to one
surface of the support member 60.
[0036] In the present embodiment, one upstream passage member,
which is the upstream passage member 30, is provided with four
connection portions, which are the connection portions 34, and the
one upstream passage member 30 is provided with four independent
upstream passages, which are the upstream passages 101. Although
the present embodiment exemplifies a structure in which one
upstream passage member (the upstream passage member 30) is
provided with four independent upstream passages (the upstream
passages 101), the structure is not particularly limited to this
but, for example, the upstream passage 101 may branch into two
after passing through the filter 35 from the side of the connection
portion 34. Not to mention, the upstream passage 101 may branch
into three after passing through the filter 35. The one upstream
passage member 30 is further provided with two of the fixing holes
38 and is fixed to the support member 60 with the fixing screws 39
at two positions. In the present embodiment, the number of upstream
passage members (the upstream passage members 30) provided to one
head unit (the head unit 1) is three. Not to mention, the method of
fixing the upstream passage members 30 to the support member 60 is
not limited to the fastening with screws but may be, for example,
bonding with a bonding agent or the like. In the present
embodiment, it is possible to easily attach/detach the upstream
passage members 30 to/from the support member 60 by fixing the
upstream passage members 30 to the support member 60 with the
fixing screws 39. Accordingly, it is possible to replace only the
upstream passage member 30 and improve a yield compared to a case
in which the passage member 20 is replaced as a whole. Moreover,
since it is possible to easily attach/detach the upstream passage
members 30 to/from the support member 60, reverse cleaning or the
like may be easily performed, in which a foreign substance in the
upstream passage 101 or on the filter 35 by causing a cleaning
liquid to flow backward through the upstream passage 101 of the
upstream passage member 30, or the like.
[0037] In the support member 60, the upstream passage members 30
are fixed to one surface in the third direction Z and the
downstream passage member 40 is fixed to the other surface. In
addition, the sealing member 50, which serves as a connecting unit
that connects the upstream passage 101 of the upstream passage
member 30 and the downstream passage 102 of the downstream passage
member 40, is provided between the support member 60 and the
upstream passage member 30.
[0038] The sealing member 50 has a resistance to liquid, such as
the ink used in the head unit 1, and may be made of an
elastically-deformable material (an elastic material), such as a
rubber or an elastomer. The sealing member 50 includes a tubular
portion 51 for each of the upstream passages 101. The inside of the
tubular portion 51 is provided with a connection passage 103. In
addition, the upstream passage 101 of the upstream passage member
30 and the downstream passage 102 of the downstream passage member
40 are allowed to communicate through the connection passage 103 of
the tubular portion 51 as described in detail below. The tubular
portion 51 is fitted around the rim of the projecting portion 41 of
the downstream passage member 40, which is described in detail
below. Since the projecting portion 41 has a cylindrical shape in
the present embodiment, the cross section of the connection passage
103 has a circular shape and a shape in which the thickness is
approximately the same along the circumferential direction, that
is, the connection passage 103 has a cylindrical shape. A
plate-like portion couples the tubular portions 51 on the side of
the upstream passage member 30 so that the plurality of tubular
portions 51 are integrated with one of the upstream passage members
30. Since each of the upstream passage members 30 is provided with
four upstream passages in the present embodiment, the sealing
member 50 that is integrally provided with the four tubular
portions 51 is employed. Since in the present embodiment, one
passage member (the passage member 20) is provided with three
upstream passage members (the upstream passage members 30), the
number of sealing members (the sealing members 50) that are
provided is the same as the number of upstream passage members (the
upstream passage members 30), that is, three.
[0039] The plate-like portion that couples the tubular portions 51
is formed so as to have a thickness that is smaller than the
thicknesses of the other regions over the periphery of the tubular
portion 51. Thus, as is described in detail below, when one surface
of the sealing member 50 is caused to abut the surface of the
upstream passage member 30 through which the upstream passage 101
is opened, only an end surface of the tubular portion 51 abuts the
periphery of the opening of the upstream passage 101 and it is
possible to increase the pressure for the hermetic sealing by
reducing the abutting area and suppress the leakage of the ink
(liquid).
[0040] The connection passage 103 of the tubular portion 51 has an
inner diameter approximately the same as the inner diameter of the
opening of the upstream passage 101 of the upstream passage member
30. The tubular portion 51 is formed so as to have an outer
diameter that is larger than the inner diameter of the upstream
passage 101. Accordingly, the upstream passage 101 and the
connection passage 103 are allowed to communicate by causing the
surface of the upstream passage member 30 through which the
upstream passage 101 is opened and the end surface of the tubular
portion 51 through which the connection passage 103 is opened to
abut each other in the penetration direction of the connection
passage 103, that is, in the third direction Z. In other words, the
upstream passage 101 and the connection passage 103 are connected
in a state in which the upstream passage member 30 and the sealing
member 50 are hermetically sealed by applying pressure in the
penetration direction of the connection passage 103 (the third
direction Z).
[0041] When the end surface of the tubular portion 51 of the
sealing member 50 and the surface of the upstream passage member 30
through which the upstream passage 101 is opened are caused to abut
each other with predetermined pressure in the third direction Z,
the tubular portion 51 of the sealing member 50 is elastically
deformed toward the recording head 10 in the third direction Z.
Thus, the support member 60 is provided with the support portion 61
so as to abut the other end surface of the tubular portion 51 of
the sealing member 50, which is opposite the end surface that abuts
the upstream passage member 30, and support the tubular portion 51
in the third direction Z.
[0042] Specifically, the inside of the support portion 61 is
provided with a tubular portion insertion hole 62, which has a
tubular shape and in which the tubular portion 51 of the sealing
member 50 is inserted on the side of the upstream passage member
30, and a projecting portion insertion hole 63, in which the
projecting portion 41 of the downstream passage member 40 is
inserted on the side of the downstream passage member 40.
[0043] The tubular portion insertion hole 62 has an inner diameter
larger than the outer diameter of the tubular portion 51 and is
formed so that the tubular portion 51 may easily be
inserted/extracted from one side.
[0044] The projecting portion insertion hole 63 has an inner
diameter that is slightly larger than the outer diameter of the
projecting portion 41 of the downstream passage member 40 and
smaller than the outer diameter of the tubular portion 51 of the
sealing member 50. Thus, a level difference 64, which is caused by
the difference in inner diameter, is formed inside the support
portion 61 and between the tubular portion insertion hole 62 and
the projecting portion insertion hole 63.
[0045] When the tubular portion 51 of the sealing member 50 is
inserted in the tubular portion insertion hole 62 of the support
portion 61, the end surface of the tubular portion 51, which is the
other end surface opposite the end surface that abuts the upstream
passage member 30, abuts the level difference 64 and as a result, a
move in the insertion direction (the third direction Z) may be
suppressed. That is, in the present embodiment, one end surface of
the tubular portion 51 of the sealing member 50 abuts the upstream
passage member 30 and the connection portion of the upstream
passage 101 and the connection passage 103 is hermetically sealed,
and the other end surface of the tubular portion 51 abuts the level
difference 64 of the support portion 61 to be supported. Thus,
since the upstream passage member 30 is fixed to the support member
60, even when the tubular portion 51 of the sealing member 50 is
pressed toward the downstream passage member 40, the repulsion
caused by the elastic deformation of the sealing member 50 is
supported by the support portion 61 of the support member 60. As a
result, no repulsion of the sealing member 50 is applied toward the
downstream passage member 40, and the upstream passage member 30
and the sealing member 50 abut each other while being pressed with
predetermined pressure.
[0046] Since one end surface of the tubular portion 51 abuts the
upstream passage member 30 and the other end surface abuts the
level difference 64 of the support portion 61 in this manner, the
support portion 61 (the level difference 64) abuts a region to
which the sealing member 50 (the tubular portion 51) on the side
opposite the surface that abuts the upstream passage member 30 and
the upstream passage member 30 apply pressure, that is, a position
that overlaps the region in which the upstream passage member 30
and the sealing member 50 abut each other and perform the hermetic
sealing. That the support portion 61 (the level difference 64)
abuts a position that overlaps the region to which the sealing
member 50 (the tubular portion 51) and the upstream passage member
30 apply pressure is rephrased as follows: when projection is
performed in the third direction Z on the region in which the
upstream passage member 30 and the tubular portion 51 of the
sealing member 50 abut each other and on the region supported by
the support portion 61 (the level difference 64) and the sealing
member 50 abutting each other, the positions of the regions overlap
each other. Since the tubular portion 51 pressed by the upstream
passage member 30 is supported by the support portion 61 on an axis
in the third direction Z in this manner, it is possible to suppress
occurrence of deformation of the tubular portion 51, such as
distortion in the first direction X or the second direction Y. If
the region in which the upstream passage member 30 presses the
tubular portion 51 and the region that the support portion 61
supports (the region that the level difference 64 abuts) are
positioned so as not to overlap each other when undergoing the
projection in the third direction Z, the tubular portion 51 may be
distorted and deformed in the first direction X and the second
direction Y and as a result, the ink (liquid) may leak from the
connection portion of the upstream passage 101 and the connection
passage 103 or the connection portion of the connection passage 103
and the downstream passage 102. In the present embodiment, the
region in which the upstream passage member 30 and the tubular
portion 51 of the sealing member 50 abut each other and the region
supported by the support portion 61 (the level difference 64) and
the tubular portion 51 of the sealing member 50 that abut each
other are positioned so as to overlap each other when undergoing
the projection in the third direction Z. Thus, it is possible to
suppress distortion and deformation of the tubular portion 51 and
suppress leakage of the ink in the connection portion of each
passage.
[0047] The downstream passage member 40 is fixed on the side of a
surface of the support member 60, which is opposite the upstream
passage member 30. The recording head 10 is fixed on the side of a
surface of the downstream passage member 40, which is opposite the
support member 60.
[0048] The downstream passage member 40 is provided with the
downstream passage 102 that communicates with the upstream passage
101 of the upstream passage member 30. The downstream passage 102
is provided so as to be opened at one end through the surface to
which the recording head 10 is fixed and be opened at the other end
through the top end surface of the projecting portion 41 that is
tubular and is provided so as to project on the side of the
upstream passage member 30.
[0049] As described above, the projecting portion 41 has an outer
diameter that is slightly smaller than the inner diameter of the
projecting portion insertion hole 63 of the support portion 61, and
is inserted in the projecting portion insertion hole 63 of the
support portion 61. The tubular portion 51 of the sealing member 50
inserted in the tubular portion insertion hole 62 is fitted around
the rim of the projecting portion 41 inserted in the projecting
portion insertion hole 63 and thus, the downstream passage 102 and
the connection passage 103 of the tubular portion 51 are connected.
Accordingly, the upstream passage 101 and the downstream passage
102 are connected (linked together) through the connection passage
103. The inner diameter of the connection passage 103 is slightly
smaller than the outer diameter of the projecting portion 41, and
when the sealing member 50 (the tubular portion 51) is elastically
deformed so as to widen the inner diameter, the inner surface of
the connection passage 103 comes into intimate contact with the
outer circumferential surface of the projecting portion 41 in a
state in which pressure is applied in the directions perpendicular
to the penetration direction of the connection passage 103 (the
third direction Z), that is, in the first direction X and the
second direction Y. In other words, the upstream passage 101 and
the connection passage 103 are hermetically sealed in a state in
which pressure is applied in the radial direction of the connection
portion (the connection passage 103). The radial direction of the
connection portion of the upstream passage 101 and the downstream
passage 102 (the radial direction of the connection passage 103) is
in the direction that crosses the direction in which the ink passes
(the penetration direction through the connection passage 103), and
is, in the present embodiment, in the plane direction including the
first direction X and the second direction Y. Although the upstream
passage 101 and the downstream passage 102 are provided so that the
ink flows along the third direction Z in the present embodiment,
the structure is not particularly limited to this but any one or
both of the upstream passage 101 and the downstream passage 102 may
be provided in the direction that crosses the third direction Z. In
this case, the radial direction of the upstream passage 101 and the
downstream passage 102 is in the direction that crosses the plane
direction including the first direction X and the second direction
Y.
[0050] In this manner, the sealing member 50 (the tubular portion
51) that hermetically seals the connection portion of the
downstream passage 102 of the downstream passage member 40 applies
pressure in the radial direction of the downstream passage 102,
that is, in the direction perpendicular to the third direction Z to
perform the hermetic sealing. As a result, the sealing member 50 is
elastically deformed in the direction perpendicular to the plane
direction of the liquid ejecting surface 12, that is, in the third
direction Z and the repulsion may suppress a press against the
recording head 10. Accordingly, it is possible to suppress
separation of the recording head 10 from the passage member 20,
separation of a layer member arranged in layers in the third
direction Z, which is not illustrated but is a constituent of the
recording head 10, and occurrence of warping on the liquid ejecting
surface 12 of the recording head 10, and it is possible to suppress
deviation from the positions at which the drops of ink are expected
to be supplied from the nozzles to an ejected medium, which may be
caused by the warping of the liquid ejecting surface 12.
[0051] As described above, the sealing member 50 that hermetically
seals the connection portion of the upstream passage 101 of the
upstream passage member 30 applies pressure in the direction in
which the ink flows through the upstream passage 101, that is, in
the third direction Z to perform the hermetic sealing. However,
since in the present embodiment, the support portion 61 is caused
to support the region in which the upstream passage member 30 of
the sealing member 50 presses the sealing member 50 in the third
direction Z, the pressure with which the upstream passage member 30
presses the sealing member 50 in the third direction Z is supported
by the support portion 61. The support member 60 that has the
support portion 61 is fixed in a region in which the support member
60 does not overlap the downstream passage member 40 or the nozzles
when undergoing projection. Thus, the pressure with which the
upstream passage member 30 presses the sealing member 50, which is
the repulsion caused by the elastic deformation, is supported by
the support portion 61 and dispersed to a fixing region in which
the support member 60 that has the support portion 61 and the
downstream passage member 40 are fixed. Accordingly, it is possible
to suppress application of the pressure against the sealing member
50 particularly to the periphery of the nozzles of the recording
head 10. As a result, it is possible to suppress separation of a
member that is a constituent of the recording head 10, separation
of the passage member 20 and the recording head 10, deviation from
the positions at which the drops of ink are expected to be
supplied, which is caused by the warping of the liquid ejecting
surface of the recording head 10, and the like.
[0052] Further, when the upstream passage member 30 and the sealing
member 50 are connected while applying pressure in the direction in
which the ink flows, that is, in the third direction Z, relative
positioning and connection of the upstream passage member 30 and
the sealing member 50 may be performed easily. If the upstream
passage 101 is provided in a projecting portion shaped like a
cylinder, similar to the downstream passage 102, and the tubular
portion 51 of the sealing member 50 is fitted around the rim of the
projecting portion so as to connect the upstream passage 101 and
the connection passage 103, the plurality of projecting portions
need to be inserted in the tubular portions 51 of the sealing
member 50 at the same time and workability decreases. Particularly,
it is difficult to visually check the connection portion of the
upstream passage member 30 and the sealing member 50 because the
support member 60 or the like hides the connection portion and
thus, it may be impossible to check the accuracy of the connection.
Besides, when an error occurs between the positions of the
plurality of projecting portions and the positions of the plurality
of tubular portions 51, the tubular portion 51 needs to be bent and
a malfunction, such as leakage of the ink, may be caused by the
poor sealing. Since in the present embodiment, the plane of the
upstream passage member 30 and the plane of the sealing member 50
are caused to abut each other in the third direction Z, pressure is
applied in the third direction Z, and the upstream passage 101 and
the connection passage 103 are allowed to communicate, the
positioning may be performed easily without any visual check. In
addition, even when an error occurs at the position of each of the
tubular portions 51 relative to the plurality of upstream passages
101, it is possible to reduce application of force in the direction
in which the tubular portion 51 is bent and suppress leakage of the
ink caused by the poor sealing.
[0053] In a method of manufacturing the head unit 1 described
above, the downstream passage member 40 and the support member 60
are fixed first, and then the tubular portion 51 of the sealing
member 50 is fitted around the projecting portion 41 provided with
the downstream passage 102. After that, the upstream passage member
30 is positioned so that the opening of the upstream passage 101
matches the tubular portion 51 of the sealing member 50 (the
opening of the connection passage 103), and the upstream passage
member 30 is fixed to the support member 60. Thus, poor sealing of
the upstream passage 101, the connection passage 103, and the
downstream passage 102 may be suppressed while performing
positioning and assembling easily. Although the connection passage
103 and the downstream passage 102 may be connected after the
upstream passage 101 and the connection passage 103 have been
connected, as described above, it is difficult and not preferable
to cause the tubular portions 51 to be fitted around the plurality
of projecting portions 41 without performing visual check.
[0054] In the present embodiment, further, a wiring substrate 70 is
provided between the downstream passage member and the support
member 60. The wiring substrate 70 is provided with wiring that is
not particularly illustrated but is connected to a pressure
generating portion provided to the recording head 10, or the like.
The wiring substrate 70 is further provided with a connector 71,
and external wiring into which a wiring connection hole 65 provided
to the support member 60 penetrates, which is not illustrated, is
connected to the connector 71. When the wiring substrate 70 is
provided in the passage member 20 in this manner, the wiring may
suffer a short circuit if the wiring substrate 70 comes into
contact with the ink. Thus, it is necessary to suppress
particularly the leakage of the ink (liquid) from the connection
portion of the upstream passage 101 and the downstream passage 102.
Since in the present embodiment, the connection portion of the
upstream passage 101 and the downstream passage 102 is sealed using
the sealing member 50 and the support portion 61 is provided, the
connection portion of the upstream passage 101 and the downstream
passage 102 may be hermetically sealed with high pressure while
suppressing the application of the pressure in the third direction
Z to the recording head 10. Accordingly, leakage of the ink may be
suppressed and occurrence of a malfunction, such as a short circuit
of the wiring, may be suppressed. Another Embodiment
[0055] Although one embodiment of the invention is described above,
the basic structure of the invention is not limited to the
above-described structures.
[0056] For example, although the first embodiment described above
exemplifies the sealing member 50 that is integrally provided with
the plurality of tubular portions 51, the structure is not
particularly limited to this but the tubular portion 51 may be an
independent tubular portion for each of the upstream passages
101.
[0057] Further, although in the first embodiment described above,
the upstream passage member 30 is made up of three members, which
are the first upstream passage member 31, the second upstream
passage member 32, and the third upstream passage member 33, the
upstream passage member 30 may be a single member or may be made up
of a plurality of members, the number of which is a number other
than three. Similarly, although in the above-described example, the
downstream passage member 40 is a single member, the structure is
not particularly limited to this but the downstream passage member
40 may be made up of two or more members.
[0058] Although the support portion 61 is provided to the support
member 60 in the first embodiment described above, the structure is
not particularly limited to this but the support portion 61 may be
provided as part of the downstream passage member 40 or the
upstream passage member 30. When, for example, the support portion
61 is integrally provided to the downstream passage member 40,
similar to the first embodiment described above, it is satisfactory
for the support portion 61, which includes the support portion 61
integrally formed and supported, to be fixed to the downstream
passage member 40 at a position that does not overlap the nozzles
of the recording head 10 when undergoing projection in the third
direction Z.
[0059] Moreover, although the first embodiment described above
exemplifies the support portion 61 that has a cylindrical shape,
the support portion 61 is not particularly limited to the structure
but may be provided to the tubular portion 51 non-continuously in
the circumferential direction because it is satisfactory for the
support portion 61 to abut an end surface of the tubular portion 51
so that a move of the tubular portion 51 in the third direction Z
is restricted. That is, the support portion 61 may be provided with
slits or the like at predetermined gaps in the circumferential
direction.
[0060] Further, although the first embodiment described above
exemplifies the passage member 20 that includes the upstream
passage member 30 provided with the upstream passage 101 and the
downstream passage member 40 provided with the downstream passage
102, when for example, the ink (liquid) is caused to circulate, the
upstream side and the downstream side may be reversed. That is, the
ink supplied to the recording head 10 may be caused to flow from
the downstream passage 102 to the upstream passage 101 to be
discharged (circulate) to the liquid retaining portion, a reservoir
in which the discharged ink is stored, or the like.
[0061] The head unit 1 according to the first embodiment described
above is mounted in an ink jet recording apparatus. FIG. 4 is a
schematic view that illustrates an example of the ink jet recording
apparatus.
[0062] In an ink jet recording apparatus I illustrated in FIG. 4,
an ink cartridge 2 that serves as the liquid retaining portion is
provided to the head unit 1 so as to be attachable/detachable. The
head unit 1 provided with the ink cartridge 2 is mounted on a
carriage 3. The carriage 3 is provided to a carriage axis 5
attached to an apparatus body 4 so as to be movable in the axis
direction.
[0063] When driving force of a drive motor 6 is transferred to the
carriage 3 through a plurality of gear wheels, which are not
illustrated, and a timing belt 7, the carriage 3 with the head unit
1 is moved along the carriage axis 5. The apparatus body 4 is
provided with a platen 8 along the carriage axis 5, and a recording
sheet S fed as a recording medium by a paper feeding roller not
illustrated, such as paper, is wound around the platen 8 to be
transported.
[0064] Although in the above-described ink jet recording apparatus
I exemplified, the head unit 1 is mounted on the carriage 3 and
moved in the main scanning direction, the structure is not
particularly limited to this but the invention may be applied to,
for example, a so-called line recording apparatus in which the head
unit 1 is fixed and printing is performed only by moving the
recording sheet S, such as paper, in the subscanning direction.
[0065] Although the above-described example exemplifies the ink
cartridge 2 as the liquid retaining portion, the liquid retaining
portion is not particularly limited to an ink cartridge but, for
example, an ink tank or the like may be fixed as the liquid
retaining portion to the apparatus body 4, and the liquid retaining
portion and the head unit 1 may be connected through a supply pipe,
such as a tube. That is, the head unit 1 is not limited to the
structure in which the liquid retaining portion is directly
connected to the connection portion 34 but the liquid retaining
portion may be connected to the connection portion 34 through a
supply pipe or the like. It is optional to mount the liquid
retaining portion in the ink jet recording apparatus I.
[0066] The invention is largely aimed at liquid ejecting heads in
general and may be applied to, for example, a recording head
included in various kinds of ink jet recording heads used in image
recording apparatuses, such as printers, a coloring material
ejecting head used to manufacture a color filter for a liquid
crystal display or the like, an electrode material ejecting head
used to form an electrode for an organic electroluminescent (EL)
display, a field emission display (FED), or the like, or a
bioorganic substance ejecting head used to manufacture a
biochip.
* * * * *