Note: Descriptions are shown in the official language in which they were submitted.
2 0 ~ 7 3 1 ~
INIC CONTAINER CARTRIDGE
AND MANUFACTURING METHOD THEREFOR
FIELD_OF THE INVENTION AND RELATED ~RT
The present invention relates to an ink
container cartridge containing ink to be supplied to
the recording head and a manufacturing method therefor~
Various types of recording apparatus for
effecting recording on a sheet of paper or OHP sheet or
the like are used, and they use various types of
recording head. The types of the recording heads
include a wire dot type, a heat sensitive type~ a heat
transfer type or an ink jet type. Among them, the ink
jet type is recently particularly noted because of its
low running cost and lost noise, since the ink is
directly ejected to the recording sheet.
The ink iet recording apparatus of the ink jet
type uses a recording head cartridge which is
detachably mountable to the recording apparatus, the
recording head cartridge comprising the recording head
and an integral ink container. In order to make the
ink replenishing operation resulting from the use-up of
the ink, the ink container (ink supply source) is made
detachably mountable to the main assembly of the
recording apparatus, so as to permit the operator
replaces the used-up ink container with a flesh ink
container. Such a type of ink container is called ink
2~5~3~
cartridge.
The ink container cartridge may include an ink
bladder coated with aluminum laminate or the like in
consideration of prevention from the ink deterioration
by being exposed to light, the sealing of the ink and
against the air~and the pressure balance in the ink
supply system. In addition, in consideration of the
easy handing of the cartridge, the ink bladder may be
accommodated in a casing~ The ink bladder is provided
with a plug made of rubber or the like. The ink supply
is established by piercing the plug with a hollow
needle of an ink supply system of the ink jet recording
apparatus main assembly. The meniscus retaining force
at the ink ejection outlets and the static head
difference between the recording head and the ink
container cartridge are balanced, and the ink is
supplied into the recording head by the capillaxy
action of the ink supply system such as tube.
However, with the conventional structure, the
ink flows in the opposite direction in the ink
container with the result of trouble in the operation.
When the recording head i5 removed from ~he main
assembly for the purpose of maintenance operation, the
connecting portion between tha ink supply system and
the recording head is opened to the air, and therefore,
the balance between the meniscus of the recording head
and the static head difference is disturbed with the
2~5~
result of the reverse flow of the ink to the ink
container, and a great quantity of the air may be
introduced in the ink supply system, that is, the tube,
for example. This will be described in detail in
comparison with the embodiment of the present
invention.
During the ejection recovery process of the
recording head, the air is positively introduced
through the ejection outlets, and then, the air is
sucked out to remove at once the various foreign
matters such as air bubbles, dust and viscosity
increased ink stagnating in the neighborhood of a
common ink chamber, together with the introduced air.
In such a case, the balance between the meniscus and
the head difference is disturbed, with the result that
the ink in the ink supply tube returns into the ink
container, and the ink supply tube is filled with the
air .
If the ink in the ink supply system flows ~ack
into the ink container, and the air is introduced, the
quantity of ink i9 significantly large in order to
recover the ejection operation by the sucking of the
ink to restabilize the ink supply system, so that the
great amount of ink i5 consumed without recording. In
the case of the recording head cartridge having the
integral recording head and the ink container, is free
of such a problem. However, the pressure in the ink
2~3~ ~
container is vacuum, and therefore, there is a
liability of introducing the air into the ink
container. If the air is introduced into the alr, no
sufficient ink supply can not be achieved with the
result of interruption of the printing operation. If
the ambient condition change occurs, particularly from
the temperature change from low temperature to the high
temperature causes expansion of the air~ with the
result of pressurized ink container. If this occurs,
the ink may leak out.
In order to solve s~ch a problem, U.S. Patent
No. 4,931,812, proposes that an "L" shaped ink passage
connecting the recording head and the ink container is
utilized, and a ball is placed therein to prevent
introduction of the air. However, the structure is not
usable with the ink container cartridge because it is
directed to the recording head cartridge.
SUMMARY OF THh INVENTION
Accordingly, it is an object of the present
invention to provide an ink container cartridge wherein
the ink supply failure due to the air introduction is
effectively prevented.
It is another object of the present invention
to provîde an ink container cartridge wherein the back-
flow of the ink is effectively prevented.
According to an aspect of the present
2~31~
--5--
invention, there is provided an ink container
cartridge, comprising: an ink containing portion; a
plug for being pierced by a hollow needle; means for
prevent.ing reverse flow of the ink to said containing
S portion, said preventing means comprising a valve, a
~irst liquid passa~e in which said valve is movable and
a second passage disposed closer to said ink containing
portion than said first passage, and said valve is
capable of closing the second passageO
According to another aspect of the present
invention, there is provided a method of manufacturing
an ink cartridge, comprising: preparing an ink
container having an ink containing portion, a liquid
passage communicating with the ink containing portion
and a plug for plugging the liquid passage; filling the
containing portion with ink; mounting a valve into the
liquid passage; mounting the plug; effecting sucking
through the plug to discharge air from said containing
portion.
According to a further aspect of the present
invention, said valve is set between the projections
before said plugging step, and the valve is urged
inwardly beyond the first projection.
According to a yet further aspect of the
present invention~ there is provided an ink jet
recording apparatus, comprising: an ink container
cartridge including an ink containing portion; a plug
2~3~ ~
for being pierced by a hollow needlei means for
preventing reverse flow of the ink to said containing
portion, said preventing means comprising a valve, a
first liquid passage in which said valve is movable and
a seco~d passage disposed closer to said ink containing
portion than said first passage, and said valve is
capable of closing the second passage; a recording head
having a portion detachably mounting said ink container
cartridge; means for r~ceiving the recording head; and
recovery means for recovering operation of said
recording head.
The recovery means may introduced the air
through the ink ejection outlets of the recording head
prior to the recovering operation.
According to the present invention, the
reverse flow of the ink to the ink container is
effectively prevented, and therefore, the introduction
of the air into the ink supply system can be prevented
when the recording head is dismounted or in the
recovery operation in which the air is introduced
through the ejection outlets. Therefore, the quantity
of the ink consumed fox the ejection recovery oper~tion
for refilling the ink in the ink.supply system or the
recording head, can be reduced.
These and other ob~ects, features and
advantages of the present invention will become more
apparent upon a consideration of the fol~owing
2~573~3
description of the pre~erred embodiments of the present
invention taken in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure~1 is a perspective view of an ink jet
recording apparatus to which the present inYention i5
applicable~
Figure 2 illustrates a recording head and a
cap therefor in the apparatus of Figure 1.
Figure 3 is a perspective view of an ink
cartridge mounting portion in the apparatus of Figure
1.
Figure 4 is a sectional view of an ink
communicatiny part of an ink cartridge according to a
first embodiment of the pxesent invention.
Figures 5A and SB are sectional views
illustrating operation of the ink cartridge of the
first embodiment.
Figure 6 illustrates operation of the air
introduction prior to the recovery operation of the ink
supply system in the ink cartridge of the first
embodiment.
Figure 7 is a sectional view illustrating the
recovery operation for the ink supply system in the
apparatus of the first embodiment.
Figure 8 is a sectional view illustrating the
2 ~
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operation when the recording head is dismounted in a
conventional apparatus.
Figure 9 is a sectional view illustrating
operation of the air introduction in the conventional
ink supply system.
Figure~10 illustrates manufacturing of the ink
cartridge in accordance with a first embodiment of the
present invention.
Figure 11 i5 a sectional view of an ink
communicating position of an ink cartridge accordiny to
a second embodiment of the present i~vention.
Figure 12 is a sectional view illustrating the
configuration of a projection in the cartridge of
Figure 11.
Figure 13 illustrates the manufacturing step
of the ink cartridge according to a second embodiment
of the present invention.
Figure 14 is a -sectional view of an ink
communicating portion of an ink cartridge according to
a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
_.
Re~erring to Figure 1, there is shown an ink
jet recording apparatus according to an embodiment of
the present invention. In this Figure, a cover has
been removed. Figure 2 shows a recording head and a
cap member of this apparatus.
~ ~ 5 7 3 ~ 1~
g
The recording head 1 is in the form of a chip
and is mountable onto a carriage 2 which is
reciprocable. The carriage 2 is provided with a
supporting member for detachably mounting the recording
S head 1 thereon and a covering mem~er (chain lines) for
protecting a substrate which constitutes a part of the
recording head 1 and which has driving circuit or the
like printed thereon.
As shown in Figure 2, the recording head 1 is
provided with 64 ejection outlets 101 at its front
side, although only three ejection outlets are shown in
Figure 2. Each of the ejection outlets 101 i5
connected with an ink passage 103 communicating
therewith. Behind the ink passage 103, there is a
common ink chamber 105 for supplying the ink to the
liquid passages 103. Each of the ink passages is
provided with an electrothermal transducer element 107
for generating thermal energy to create film boiling to
eject droplets of the ink through the ejection outlet
and is also provided with electrode wiring ~or
supplying electric power to the electrothermal
transducer element 107. To the common chamber 1 a3 ~- the
ink is supplied through a supply tube 109,
The electrothermal transducer elements 107 and
the electrode wiring are formed on a silicone or the
like ~ubstrate 111 through film formation process. By
laminating partition forming members 113 of resin or
20~31~
- 1 0 -
glass material and a top plate 115 or the like, the
ejection outlets 101, the ink passages 103 and a common
liquid chamber 105 are formed. Behind them on the
recording head 1, the driving circuits are also printed
on the substrate to drive the electrothermal transducer
elements in accordance with the recording signal.
On the carriage 2, there is a connector base
plate 12 connected with a connector 9, behind the
recording head 1. The connector base plate 12 has
connectors 9 for electric connection with the recording
head 1 and connectors for connection with a flexible
cable connected with a control circuit of the main
assembly of the recording apparatus. The connector
base plate 12 is provided with capacitors and
resistors, which are effective to compensate voltage
drop of the voltage source through the flexible cable
and prevent introduction of noise. The connector base
plate 12 is supported on a sliding member which slides
in accordance with opening and closing of the cover
member to connect the connector 9 with the contacts of
the recording head 1.
An engaging portion 2a of the carriage 2 is
slidably and rotatably engage with a guide shaft 3
The guide shaft 3 is extended in a direction
perpendicular to the direction of recording material
feeding over a range larger than the width of the
recording material such as recording sheet. The
2 ~ 5
- 1 1 -
carriage 2 is engaged with a part of an unshown belt
stretched in parallel with the guiding shaft 3. The
belt is driven by a carriage motor not shown to move
the carriage 2 along the guide shaft 3, that is, in the
scanning direction. The carriage 2 and the recording
head 1 are rotatable about the guiding shaft 3 by its
weight to urge a sheet confining plate 8 through a
sliding member of the carriage 2. By doing so, a
predetermined interval is assured between the recording
sheet and the recording head 1 in accordance with the
thickness of the recording sheet.
The recording sheet 6 is fed from an unshown
sheet feeding cassette or is manually fed and is
supplied to the main assembly of the recording
apparatus through a sheet inlet pxovided by a top paper
guide 7a and a bottom paper guide 7b. The top paper
guide 7a is connected with the sheet confining plate 8
having a curvature. The sheet confining plate 8 is
urged to the sheet feeding roller 5, and the friction
between the recording sheet with the recording sheet by
the urging force is made smaller by selection of the
material than the friction force between the sheet
feeding roller and the recordlng sheet. The bottom
paper guide 7b extends to the position where the sheet
feeding roller 5 is dlsposed in parallel with the sheet
confining plate 8.
The recording sheet 6 thus supplied is fed one
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by one line upwardly by the rotation of the sheet
feeding roller. The recording sheet slides on a platen
7 in the form of a plate while keeping a predetermined
space from the recording head 1 by the sheet confining
plate and the platen 7. The recording head 1 ejects
the droplets of the ink for the recording region of the
recording sheet to effect one line recording, while it
is scanningly moved. Then, the recording shee~ is fed
by one line, and by repeating these operations, and the
character and/or images are recorded on the sheet
sequentially. The recording sheet 6 now having the
characters and/or the images is discharged onto a sheet
discharging tray by discharging rollers 4 and spurs 40a
and 40b disposed above the recording sheet passage.
Five pairs of spurs 40a and 40b are provided
corresponding to the discharging rollers 4 and is
provided with spur cleaners between them. Mem~er for
supporting the spurs and spur cleaners are omitted in
Figure 1. The spurs 40a urge the recording sheet to
the discharging rollers, and the spurs 40b limit the
conveying passage of the recording sheetO The sheet
discharging roller 4 is rotated to provide a peripheral
speed which is larger than that of the sheet feeding
roller 5, by which the recording sheet 6 is pulled
upwardly in the region constituting the recording
region so as to avoid the recording sheet 6 rising from
the platen 7.
20573~
-13-
Adjacent a home position of the recording head
1 continuing from the scanning region, -there is a set
of ejection recovery mechanisms, such as a blade 26 for
removing by wiping action ink droplets ~mist) dust or
the like on the ejection side surface where the
eiection outlets are disposed, absorbing material 25
for removing mainly by absorption ink droplets or the
like on the ejection side sur~ace, and a cap 13 for
hermetically capping the ejection side surface for
permitting idle ejections and ink sucking. They are
integrally supported on a supporting member 14 for
movement toward an away from the moving region of the
recording head 1. They are operated proper timings.
The ink is sucked from the capped space through a tube
131 and by a pump 24 connected with the tube 131~ Upon
the capping, the engagement is established between a
hole formed in a capping arm 17 mounted on a side of
the supporting member for the gap 13 and a projection
on the carriage 2 so as to prevent rearward rotation of
the recording head 1, thus assuring the capping of the
cap 13 to the ejection side surface. The cap 13 is
made of elastic member such as rubber, and using the
elasticity thereof, the air is urged into the recording
head through the ejection outlets, when it is engaged
with the recording head 1.
The rotational driving force of the fe~d motor
21 is used to rotate the sheet feeding roller 5 and the
sheet discharging roller 4 and to operate the ejection
recovery mechanism, that is, to move the cap 13, the
blade 26 and the absorbing material 25 toward and away
from the recording head and to carry out the sucking
operation with the pump 24. More particularly, the
rotational driving force of the feed motor mounted on a
part of the main assembly frame is transmitted to a
transmission gear train 19. The gear grain 19 is
effective to select proper gears for movement of the
carriage 2, the scanning movement of the recording head
1, movement of the recording head 1 to the home
position or to the ejection recovery position and for
stoppage at this position, by the selection gears (not
shown) in response to these operations. The rotation
of the gears in the gear train 19 is transmitted
.
through an intermediate gear 20 to the sheet feeding
roller 5 and the sheet discharging roller 4, and to an
integral cap 13 or the like through a cam 16, and is to
the pump 24 through a pump gear 22 and a pump cam 23
2~ As regards the ink supply to the recording
head 1, a hollow needle 314 pierces a plug of an ink
cartridge 27 mounted on the main assembly of the
recording apparatus, and a flexible tube capable of
followiny movement of the carriage 2 is used. As will
be understood from Figure 1 and other drawings, the
cartridge 27 is at a vertical level lower than the
ejection outlets of the recording headO The position
-15- 2 ~573~. a
of the carriage 2 is detected by counting number of
steps of the carriage motor on the basis of a reference
position where the home position sensor 11 of the
carriage 2 corresponds to a home position detecting
flag disposed adjacent an end of the moving region of
the carriage 2.
Figure 3 illustrates the interconnection
between the ink cartridge 27 and the main assembly.
Designated by reference numerals 271 and 340 are
1o cartridge casing and an ink bladder for accommodating
the ink to be supplied, which is accommodated in turn
in the casing 271. The bladdex has a rubber plug 342.
The needle 314 is inserted into the plug 342, and
further insertion permits communication with the ink.
An absorbing material 344 functions to accommodate
residual ink discharged by the operation o~ the
ejection recovery mechanism through a residual ink pipe
318 and is connected with an ink absorbing material
disposed below the ink bladder.
A wiring pattern 346 is provided on the top
surface of the ink cartridge 27, and the controller of
the main assembly is able to detect presence or absence
of the ink cartridge in accordance with connection or
disconnection between contact 306A and 306B through the
pattern 346. The pattern may be changed in accordance
with the color or density of ths ink in the resistance
of the wiring pattern, and then, th~ controller of the
3 ~ 3
~16-
main assembly is able to aware of the information.
A click 320 functions as a fastener for the
ink cartridge 27, and is provided one at each side o~
the cartridge receptor. The click 320 flexes by its
elasticity upon engagement with a side surface of the
cartridge 27 when it is inserted or removed, so that
the insertion or removal action of the cartridge 27 ls
permitted, while holding the cartridge 27 at a proper
position by restoring its original configuration when
it is received by a recess 332 of the cartridge 27.
Figure 4 shows an example of the ink
communicating portion of the ink cartridge. Designated
by a reference 351 is a passage forming member in the
ink bladder 340, which is effective to provide the
liquid passage 352. The passage 352 is in a circular
form having a diameter D3 at a portion 3S3, and a
diameter D2 which is smaller than the diameter D3 in
the portion 355. The large diameter and small diameter
portions are connected by a portion 357. A bal~ 361
functions as a valve and is made of polytetrafluoro-
ethylene resin and has a diametPr D1 which is smaller
than the diameter ~3 of the passage portion 353 and- :
which is larger than the dlameter D2 of the passage
portion 355. The plug 342 made of rubber or the like
co~ers a pro~ection 351A from the passage forming
member 351 from which the passage portion 353 is
formed, and is held on the lnk bladder 340 by a
3 ~ ~5
-17-
confining member 344.
During the ink supply in the normal recording
and in the ejection recovery operation, as shown in
Figure 5A, the ball 361 moves from the position
indicated by the chain line in the feeding direction by
the force resul~ing from the ink supply from the ink
bladder, for example, the flow of the ink. It abuts a
tip end of the needle 314, as indicated by the solid
lines, and therefore, the tip end is tapered a~
indicated by a reference 31 4Ar the flow of the ink is
not obstructed, and is supplied to the ink supply
system as indicated by an arrow.
When, on the other hand, the recording head 1
is removed from the main assembly or when the air is
charged with the aid of the cap 13, the ink once flows
back to the bladder, but as shown in Figure 5B, the
ball 361 moves in the opposite direction by the force
resulting from the reverse flow from the position
indicated by the chain line, until it closes the
passage portion 355 as shown by the solid line~ It is
retained thereby the force from the ink, so that the
backward flow of the ink toward the ink bladder 341 is
stopped.
The position of the tip end 314A of the needle
314 is so determined that it pushes the ball 361 but
does not close the passage. This is accomplished by
determining the dimension of the needle and the
mounting position thereof or the like so that the
positional relations as shown in Figure 5 is
established at the click position.
The advantageous effects of the present
invention will be described with respect to the
ejection recover,y operation.
Referring to Figures 6 and 7, there is
illustrated an ink supply system in the air charging
and sucking operation for the purpose of ejection
1~ recovery. An ink absorbing material 281 is disposed at
the bottom of the cartridge 27. A subordinate
container 121 is provided to trap the air in the ink
supply system and to prevent transmission of the
pressure change resulting from the carriage movement to
the recording head. A tube 123 functions to connect
the ink cartridge 27 and the subordinate container 121.
~ filter 125 functions to remove the dust or fine air
bubbles from the ink introduced into the common chamber
105 from the subordinate tank 121. A tube 127 provides
2~ communication between the subordinate tank 121 and the
pump 24. When the liquid level of the subordinate tank
is to be adjusted, the liquid is sucked through the
tube 127. The tube 127 is provided with a valve 129
As shown in Figure 6, in the recovery
operation, the va~lve 129 takes its closing position,
the air is charged into the eiection outlets by one or
repeated abutment action of the elastic cap 13 to the
2~3~
-1 9 -
recording head 1 with or without the aid of pressing
pump. The air reaches to the common chamber 105, but
in the ink cartridge 27, the ball 361 closes the
passage 352, and therefore, the air is not introduced
into the ink bladder 341. Therefore, the cartridge
failure as a re~ult of air introduction does not
result.
As shown in Figure 7, the valve 129 is then
closed, and the pump 24 is operated to effect the
sucking action. At this time, the ball 361 closes the
passage, and therefore, the ink is permitting to flow
out to the supply system. The charged air and the ink
are sucked into the cap 23 or to the pump 24, so that
the ink is refreshed. At this time, the sucking
operation is aIso effected to the subordinate container
121. In this embodiment, the air is not introduced
improperly in the bladder, and therefore, the air
bubble is prevented from entering the ink, and the
quantity of the ink consumed for the sucking operation
is small.
In the case of the cartridge 27 without the
check valve for preventing the reverse flow o~ the -ink
into the ink bladder 340' as shown in Figures 8 and 9,
when the recording head is dismounted or when the
ejection recovery operation chargss the air into the
recording head, the pressure balance between the ink
container and the ink supply is disturbed with the
3 ~ ~
-20-
result of improper air introduction, and therefore,
larger sucking force is required to suck the ink to the
recording head, and the quantity of the ink consumed in
the subsequent sucking operation is larger.
It would be considered to dispose the
structure for preventing the improper air
introduction in a position halfway of the ink supply
system. However, in order to smoothly and effactively
operate the valve, the preferable position is such that
the force provided by the ink is larger, that is, the
static head difference is larger. From this
standpoint, the position in the ink cartridge 27 is
preerable. In addition, in order to effectively
operate the valve, the non-existence of the air at the
position is preferable, and therefore, the position is
further pre~erably suck that the air is not introduced
along the pipe wall of the supply system or by the
charging of the air. The recording apparatus of this
embodiment is in the form of a serial scan type
printer, and therefore a part of the ink supply system
is made of flexible tube to follow the movement of the
recording head. The structure described above is
hardly influencea by the motion of the ink xesulting
from the scannlng movement, and therefore, the
erroneous operation of the valve hardly occurs~
Figure 10 iIlustrates an example of
manufacturing of the cartridge 27. At step STPl, the
-21- ~73~
ink bladder 341 is filled with the ink. At step STP3~
the ball 361 is set in the passage 352, and th~reafter
the rubber plug 342 is set at step STP5. Then, the ink
bladder is accommodated in the cartrldge casing, and
the cover is mounted, thus completing the assembling
(STP). At step STP9, a hollow needle is pierced to
effect sucking operation to remove the air bubbles from
the bladder. Then, the next step (inspection and
package~ is carried out. In this example, the
confining member 344 is integral with the casing and
the cover.
By the sucking operation at step STP9, the
slight vacuum is produced in the ink bladder, and
therefore, the ball 361 is closely contacted to the
passage wall 355, and therefore, the ink leakage is
effectively prevented when it is carried around.
Figure 11 shows an ink communicating portion
of the ink cartridge 27 according to another embodiment
of the present invention. The same reference numerals
as in Figure 4 are assigned to the corresponding
elements. In this Figure, designated by a reference
numeral 371 is a passage forming member for forming a
liquid passage 372. The liquid passage 372 includes a
passage portion 373 having a cirGular cross-section and
a passage portion 375 having a diameter smaller than
that of the passage portion 373. It also incIudes a
portion communicating these passage portionsO These
D ~ ~'
--22--
structures are similar as in the foregoing embodiment.
In this embodiment, however, there are projections 379A
and 379B projected inwardly at the passage portion 373.
During the manufacturing step, the ball 361 is
temporarily held betw~en the projections. To
accomplish this, the inside diameters D4 of the
projections 379A and 379B are smaller than the diameter
D1 of the ball 361. The projections 379A and 379B are
preferably of plural projections along the passage 373
wall as shown in Figure 12 rather than in the form of a
continuous annular projections, in consideration of the
temporary supporting of the ball 361, filling of the
bladder with the ink, setting of the ball 361 to the
shown position and the ink supply during recording
operation. Then, the ball ~s easily set beyond the
projections, and the ink passage is provided for
filling the bladder with the ink between the divided
projections. The intervals between the projections
379A and 379B are so selected that it is larger than
the diameter D1 of the ball 361. By mounting the
cartridge to the apparatus, the needle 314 pushes the
ball 361 beyond the projection 379B. To accomplish
this, the tip end 314A of the needle is preferably
reaches a position more than D1/2 away from the
projection 379B toward the ink bladder side.
In this embodiment, the improper air
introduction by the reverse flow of the ink can be
2~3~ ~
--23-
similarly prevented, and therefore proper ink supply
can be maintained. Similarly to the foregoing
embodiment, the tip end position of the needle 314 is
so determined that it does not urge the ball 361 to
the passage portlon 375. The end position is,
however, is abo~e the projection 379B so as to prevent
the contact between the ball 361 and the tip end, and
therefore, the damage of the ball 361 or the needle
314 by the contact can be avoided. The distance t
between the inside bottom of the plug 342 and the top
surface of the projection 371A of the passage forming
member 371 covered by the plug 342 is not particularly
considered, because the ball 361 does not all in this
embodiment.
Figure 13 illustrates the manufacturing step
of the cartridge 27. At step STP11, the ball 361 is
pressed to between the upper and lower projections 379A
and 379B of the passage forming member 371 of the ink
bladder 340. At step STP13, the rubber plug 342 is
set. Thereafter, the ink bladder 340 is accommodated
in the cartridge casing, and the cover is mounted, thus
completing the assembling of the cartridge 27 (step-
1 5 ) ,.
Then, at step STP17, the proper hollow needle
25 N is pierced into the plug 342 to supply the ink anddischarge the air. At this time, the ~low of the ink
and the air are through the clearance between the
7~3
-24-
segments of projections 379A and 379B. After the
filling operation is completed, a proper pushing rod B
(the needle N may be usable for this purpose) is used
to push the ball 361 to below the projection 379B, at
step 19. Then, the package i5 processed to the next
inspection and ~ackage.steps. The upper projections
379A is not always necessary from the standpoint of the
function of the ink cartridge. However, in order to
prevent falling of the ball 361 between the step STP11
and the step STP13, and in order to prevent vibration
or movement of the ball 361 when the ink is injected at
step STP11, thus avoiding damage by the contact between
the needle N and the ball 361, it is preferable to
provide the upper projections 379A.
The ink cartridge may be put on sale with the
ball 361 placed between the projections 379A and 379B.
In this case, by mounting the cartridge in the
apparatus, the ink supply needle urges the ball 361.
Figure 14 illustrates an ink cartridge
according to a third embodiment which is a modification
of the first embodiment. This embodiment is similax to
Figure 4 embodiment with the exception that the passage
forming member 381 having a passage portion 385 with an
inside diameter which is smaller than the ball 361 is
mounted to the outlet side of the passage forming
member 351. During the normal ink supply, the end of
the needle 341 is placed outside the passage porti.on
~73~
-25-
385, so that the ink supply is not obstructed.
The ink reverse preventing effect is the same
as in the foregoing embodiments. In this embodiment,
the ink leakage from the ink cartridge 27 after it is
removed after use-up of the cartridge can be
accomplished. If the pLug 342 is deteriorated in its
material with time, the pierce by the needle 314 is not
completely closed when the cartridge is removed fxom
the main assembly of the recording apparatus. If this
is the case, the remaining ink may leak out. According
to this embodiment, however, the leaking motion of the
ink is effective to displace the ball 361 toward the
outlet so as to close the passage 395. Therefore, the
leakage of the ink can be prevented.
15The passage of this embodiment can be formed
through the similar steps as in Figure 10 but with an
additional step between the step STP3 and the step STP5
a step of mounting the member 381 by bonding or the
like. In this embodiment, the clearance t is not
particularly considered. This is similar to the case
of the second embodiment.
The present invention is particularly suitably
usable in an ink jet recording head and recording
- apparatus wherein thermal energy by an electrothermal
transducer, laser beam or the like ls used to cause a
change of state of the ink to eject or discharge the
ink. This is because the high density of the picture
2~3~
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elements and the high resolution of the recording are
possible.
The typical structure and the operational
principle are preferably the ones disclosed in U.S.
Pa~ent Nos. 4,723,129 and 4,740,796. The principle and
structure are applicable to a so-called on-demand type
recording system and a continuous type recording
system. Particularly, however, it is-suitable for the
on-demand type because the principle is such that at
least one driving signal is applied to an
electrothermal transducer disposed on a liquid ~ink)
retaining sheet or liquid passage, the driving signal
being enough to provide such a quick temperature rise
beyond a departure from nucleation boiling point, by
which the thermal energy is provided by the
electrothermal transducer to produce film boillng on
the heating portion of the recording head, whereby a
bubble can be formed in the liquid tink) corresponding
to each of the driving signals. By the production,
dPvelopment and contraction of the the bubble, the
liquid (ink) is ejected through an ejection outlet to
produce at least one droplet. The driving signal is
preferably in the form of a pulse, because the
development and contraction of the bubble can be
effected instantaneously, and therefore/ the liquid
(ink) is ejected with quick response. The driving
signal in the form of the pulse is preferably such as
2 ~
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disclosed in U.S. Patents Nos. 4,463,359 and 4,345,262.
In addition, the temperature increasing rate of the
heating surface is preferably such as disclosed in U.S.
Patent No. 4,313,124.
The structure of the recording head may be as
shown in U.S. Patent Nos. 4,558,333 and 4,45g,600
wherein the heating portion is disposed at a bent
portion, as well as the structure of the combination of
the ejection outlet, liquid passage and the
electrothermal transducer as disclosed in the above-
mentioned patents. In addition, the present invention
is applicable to the structure disclosed in Japanese
Laid-Open Patent Application No. 123670/1984 wherein a
common slit is used as the ejection outlet for plural
electrothermal transducers, and to the structure
disclosed in Japanese Laid-Open Patent Application No.
138461/1984 wherein an opening for absorbing pressure
wave of the thermal energy is formed corresponding to
the ejecting portion. This is because the present
invention is effective to perform the recording
operation with certainty and at high efficiency
irrespective of the type of the recording head.
The present invention is effectively
applicable to a so-called full-line type recording head
having a length corresponding to the maximum recording
width. Such a recording head may comprise a single
recording head and plural recording head combined tv
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-28-
cover the maximum width.
In addition, the present invention is
applicable to a serial type recording head wherein the
recording head is fixed on the main assembly, to a
replaceable chip type recording head which is connected
electrically with the main apparatus and can be
supplied with the ink when it is mounted in the main
assembly, or to a cartridge type recording head having
an integral ink container.
The provisions of the recovery means and/or
the auxiliary means for the preliminary operation are
preferable, because they can further stabilize the
effects of the present invention. As for such means,
there are capping means for the recording head,
cleaning means therefor, pressing or sucking means r
preliminary heating means which may be the
electrothermal transducer, an additional heating
element or a combination thereof. Also, means ~or
effecting preliminary ejection ~not for the recording
operation) can stabilize the recording operation.
As regards the variation of the recording head
mountable, it may be a single corresponding to a single
color ink, or may be plural corresponding to the
pluxality of ink materialæ having different recording
color or density~ The present invention is effectively
applicable to an apparatus having at least one of a
monochromatic mode mainly with black, a multi-color
2~73.~
-29-
mode with different color ink materials and/or a full-
color mode using the mixture of the colors, which may
be an integrally formed recording unit or a combination
of plural recording heads.
Furthermore, in the foregoin~ embodiment, the
ink has been liquid. It may be, however, an ink
material which is solidified below the room
temperature but liquefied at the room temperature.
Since the ink is controlled within the temperature not
lower than 30 C and not higher than 70 C to
stabilize the viscosity o the ink to provide the
stabiliæed ejection in usual recording apparatus of
this type, the ink may be such that it is liquid
within the temperature range when the recordiny signal
is the present invention is applicable to other types
of ink. In one of them, the temperature rise due to
the thermal energy is positively prevented by
consuming it for the state change of the ink from the
solid state to the liquid state. Another ink material
is solidified when it is le~t, to pxevent the
evaporation of the ink. In aither of the cases, the
application of the recording sLgnal producing thermal
energy, the ink is liquefied, and the liquefied ink
may be ejected. Another ink material may start to be
solidified at the time when it reaches the recording
material. The present invention is also applicable to
such an ink material as is liquefied by the
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-30-
application of the thermal energy. Such an ink
material may be retained as a liquid or solid material
in through holes or recesses ormed in a porous sheet
as disclosed in Japanese Laid-Open Patent Application
No. 56847/1979 and Japanese Laid-Open Patent
Application No. 71260/1985. The sheet i5 faced to the
electrothermal transducers~ The most effective one
for the ink materials described above is the film
boiling system.
The ink jat recording apparatus may be used as
an output terminal of an information processing
apparatus such as computer or the like, as a copying
apparatus combined with an image reader or the like, or
as a facsimile machine having information sending and
receiving functions.
As described in the foregoing, according to
the present invention, the reverse flow of the ink to
the ink container is effectively prevented. Therefore,
the introduction of the air into the ink supply system
during the ejection recovery operation including the
air charging through the e;ection outlets and when the
recording head is dismounted. Thus, the consumption of
the ink in the recovery operation or the ink refilling
operation can be reduced.
While the invention has been described with
reference to the structures disclosed herein, lt is not
confined to the details set forth and this application
2 ~
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is intended to cover such modifications or changes as
may come within the purposes of the improvemenks or the
scope of the following claims.
1 0
