FIELD OF THE INVENTION AND RELATED ART
[0001] The present invention relates to an ink container cartridge containing ink to be
supplied to the recording head and a manufacturing method therefor.
[0002] 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.
[0003] The ink jet 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 cartridge.
[0004] 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 capillary action of the ink
supply system such as tube.
[0005] 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 is removed from the main assembly for the purpose of maintenance operation, the
connecting portion between the 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 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.
[0006] 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.
[0007] If the ink in the ink supply system flows back into the ink container, and the air
is introduced, the quantity of ink is 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 is 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 container is vacuum, and
therefore, there is a liability of introducing the air into the ink container. If
the air is introduced into the air, 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.
[0008] In order to solve such 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 THE INVENTION
[0009] 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.
[0010] It is another object of the present invention to provide an ink container cartridge
wherein the back-flow of the ink is effectively prevented.
[0011] According to an aspect of the present invention, there is provided an ink container
cartridge, comprising: an ink containing portion; a plug for being pierced by a hollow
needle; 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 second passage disposed closer to said ink containing portion than said
first passage, and said valve is capable of closing the second passage.
[0012] 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.
[0013] 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.
[0014] 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 for being pierced by a hollow needle; 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 second 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 receiving the recording head; and
recovery means for recovering operation of said recording head.
[0015] The recovery means may introduced the air through the ink ejection outlets of the
recording head prior to the recovering operation.
[0016] 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 for the ejection recovery operation for refilling
the ink in the ink supply system or the recording head, can be reduced.
[0017] These and other objects, features and advantages of the present invention will become
more apparent upon a consideration of the following description of the preferred embodiments
of the present invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 is a perspective view of an ink jet recording apparatus to which the present
invention is applicable.
[0019] Figure 2 illustrates a recording head and a cap therefor in the apparatus of Figure
1.
[0020] Figure 3 is a perspective view of an ink cartridge mounting portion in the apparatus
of Figure 1.
[0021] Figure 4 is a sectional view of an ink communicating part of an ink cartridge according
to a first embodiment of the present invention.
[0022] Figures 5A and 5B are sectional views illustrating operation of the ink cartridge
of the first embodiment.
[0023] 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.
[0024] Figure 7 is a sectional view illustrating the recovery operation for the ink supply
system in the apparatus of the first embodiment.
[0025] Figure 8 is a sectional view illustrating the operation when the recording head is
dismounted in a conventional apparatus.
[0026] Figure 9 is a sectional view illustrating operation of the air introduction in the
conventional ink supply system.
[0027] Figure 10 illustrates manufacturing of the ink cartridge in accordance with a first
embodiment of the present invention.
[0028] Figure 11 is a sectional view of an ink communicating position of an ink cartridge
according to a second embodiment of the present invention.
[0029] Figure 12 is a sectional view illustrating the configuration of a projection in the
cartridge of Figure 11.
[0030] Figure 13 illustrates the manufacturing step of the ink cartridge according to a
second embodiment of the present invention.
[0031] 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
[0032] Referring 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.
[0033] 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 head 1 thereon and a covering member (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.
[0034] 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 is 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 for supplying electric power to the electrothermal transducer element 107.
To the common chamber 103, the ink is supplied through a supply tube 109.
[0035] The electrothermal transducer elements 107 and the electrode wiring are formed on
a silicone or the like substrate 111 through film formation process. By laminating
partition forming members 113 of resin or 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.
[0036] 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.
[0037] 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 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.
[0038] 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 provided 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 recording sheet. The bottom paper guide 7b extends to the position where the
sheet feeding roller 5 is disposed in parallel with the sheet confining plate 8.
[0039] The recording sheet 6 thus supplied is fed one 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 sheet 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. Member 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 sheet. 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.
[0040] 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 ejection outlets are disposed, absorbing material 25 for removing mainly by absorption
ink droplets or the like on the ejection side surface, 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.
[0041] The rotational driving force of the feed motor 21 is used 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.
[0042] 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 following 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 head. The position 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.
[0043] Figure 3 illustrates the interconnection between the ink cartridge 27 and the main
assembly. Designated by reference numerals 271 and 340 are cartridge casing and an
ink bladder for accommodating the ink to be supplied, which is accommodated in turn
in the casing 271. The bladder 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 of
the ejection recovery mechanism through a residual ink pipe 318 and is connected with
an ink absorbing material disposed below the ink bladder.
[0044] 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 the ink in the resistance of the wiring pattern, and then, the controller
of the main assembly is able to aware of the information.
[0045] A click 320 functions as a fastener for the ink cartridge 27, and is provided one
at each side of 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 is 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.
[0046] 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 353, 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 ball 361 functions as a valve and is made of polytetrafluoroethylene
resin and has a diameter D1 which is smaller than the diameter D3 of the passage portion
353 and which is larger than the diameter D2 of the passage portion 355. The plug
342 made of rubber or the like covers a projection 351A from the passage forming member
351 from which the passage portion 353 is formed, and is held on the ink bladder 340
by a confining member 344.
[0047] 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
linein the feeding direction by the force resulting 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 as indicated by
a reference 314A, the flow of the ink is not obstructed, and is supplied to the ink
supply system as indicated by an arrow.
[0048] 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.
[0049] 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.
[0050] The advantageous effects of the present invention will be described with respect
to the ejection recovery operation.
[0051] 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 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. A 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 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.
[0052] As shown in Figure 6, in the recovery operation, the valve 129 takes its closing
position, the air is charged into the ejection outlets by one or repeated abutment
action of the elastic cap 13 to the 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 result of air introduction
does not result.
[0053] 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 also 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.
[0054] In the case of the cartridge 27 without the check valve for preventing the reverse
flow of 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 charges the air into the
recording head, the pressure balance between the ink container and the ink supply
is disturbed with the 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.
[0055] 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
effectively 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 preferable. 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 preferably 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 influenced by the motion
of the ink resulting from the scanning movement, and therefore, the erroneous operation
of the valve hardly occurs.
[0056] Figure 10 illustrates an example of manufacturing of the cartridge 27. At step STP1,
the ink bladder 341 is filled with the ink. At step STP3, the ball 361 is set in the
passage 352, and thereafter the rubber plug 342 is set at step STP5. Then, the ink
bladder is accommodated in the cartridge 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.
[0057] 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.
[0058] 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 circular cross-section and a passage
portion 375 having a diameter smaller than that of the passage portion 373. It also
includes a portion communicating these passage portions. These 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 between 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 is 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.
[0059] In this embodiment, the improper air introduction by the reverse flow of the ink
can be 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 portion 375. The end position is,
however, is above 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 fall
in this embodiment.
[0060] 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
15).
[0061] Then, at step STP17, the proper hollow needle N is pierced into the plug 342 to supply
the ink and discharge the air. At this time, the flow of the ink and the air are through
the clearance between the 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 is processed to the next inspection and package 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.
[0062] 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.
[0063] Figure 14 illustrates an ink cartridge according to a third embodiment which is a
modification of the first embodiment. This embodiment is similar 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 portion 185, so that the ink supply is not
obstructed.
[0064] 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 142 is deteriorated in its
material with time, the pierce by the needle 114 is not completely closed when the
cartridge is removed from 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 161 toward the outlet
so as to close the passage 195. Therefore, the leakage of the ink can be prevented.
[0065] The passage of this embodiment can be formed through the similar steps as in Figure
10 but with an additional step between the step STP1 and the step STP5 a step of mounting
the member 181 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.
[0066] 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 is 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 elements and the high resolution
of the recording are possible.
[0067] The typical structure and the operational principle are preferably the ones disclosed
in U.S. Patent Nos. 4,721,129 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 boiling on the heating portion of the recording head, whereby a bubble
can be formed in the liquid (ink) corresponding to each of the driving signals. By
the production, development and contraction of the the bubble, the liquid (ink) is
ejected through an ejection outlet to produce at least one droplet. The driving signal
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 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.
[0068] The structure of the recording head may be as shown in U.S. Patent Nos. 4,558,333
and 4,459,600 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.
[0069] 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 to cover
the maximum width.
[0070] 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.
[0071] 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, preliminary heating means which may be
the electrothermal transducer, an additional heating element or a combination thereof.
Also, means for effecting preliminary ejection (not for the recording operation) can
stabilize the recording operation.
[0072] 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 plurality of ink materials
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 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.
[0073] Furthermore, in the foregoing 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 of the ink to provide the
stabilized ejection in usual recording apparatus of this type, the ink may be such
that it is liquid within the temperature range when the recording 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 left, to prevent the evaporation of the ink. In either of the cases, the
application of the recording signal 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 application of the thermal
energy. Such an ink material may be retained as a liquid or solid material in through
holes or recesses formed 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 is faced to the electrothermal transducers. The most effective one for the
ink materials described above is the film boiling system.
[0074] The ink jet 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.
[0075] 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 ejection 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.
[0076] While the invention has been described with reference to the structures disclosed
herein, it is not confined to the details set forth and this application is intended
to cover such modifications or changes as may come within the purposes of the improvements
or the scope of the following claims.
1. An ink container cartridge, comprising:
an ink containing portion;
a plug for being pierced by a hollow needle;
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 second passage disposed closer to said ink containing portion than said first passage,
and said valve is capable of closing the second passage.
2. A cartridge according to Claim 1, wherein the first passage has a length larger than
an insertion length of the needle to avoid influence to movement of the valve.
3. A cartridge according to Claim 1, wherein a diameter of the second passage is smaller
than that of the first passage.
4. A cartridge according to Claim 1, wherein said first passage is provided with an inward
projection.
5. A cartridge according to Claim 1, wherein the first passage is provided with smaller
diameter portion at a side away from said ink containing portion.
6. 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.
7. A method according to Claim 6, wherein said passage is provided with a projection
for preventing movement of the valve away from the containing portion but permits
passage of the ink.
8. A method according to Claim 6, wherein said passage further comprises a second projection,
and said valve is accommodated between the first and second projections.
9. A method according to Claim 8, wherein said valve is set between the projections before
said plugging step, and the valve is urged inwardly beyond the first projection.
10. A cartridge according to Claim 2, further comprising a third passage extending from
said second passage which can be closed by said valve.
11. An ink jet recording apparatus, comprising:
an ink container cartridge including an ink containing portion; a plug for being
pierced by a hollow needle;
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 second 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 receiving the recording head; and
recovery means for recovering operation of said recording head.
12. An ink jet recording apparatus according to Claim 11, wherein said recovery means
charges air into said recording head.
13. An apparatus according to Claim 11, wherein said recording head including means for
producing thermal energy for producing film boiling to eject the ink.