Information
-
Patent Grant
-
6554391
-
Patent Number
6,554,391
-
Date Filed
Thursday, July 20, 200024 years ago
-
Date Issued
Tuesday, April 29, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Barlow; John
- Liang; Leonard
Agents
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
A self-cleaning printer system (400) with cleaning liquid (300) and cleaning mechanism (140) with a rotating disk cleaning assembly (32) can be used to remove contaminants from a print head (16) in the self-cleaning ink jet printer system (400). A rotating disk cleaning assembly (32) is disposed relative to the surface (15) of a print head (16) for directing a flow of cleaning liquid (300) along the surface (15) and to direct sliding contact of a disk (190) to clean the contaminants from the surface (15). The rotating disk cleaning assembly (32) is configured to introduce cleaning liquid (300) to the print head surface (15) to facilitate and augment cleaning by the disk (190). Flow of the cleaning liquid (300) is facilitated by vacuum pump (36) which directs cleaning liquid (300) from a cleaning liquid reservoir (270) to the rotating disk cleaning assembly (32).
Description
FIELD OF THE INVENTION
This invention generally relates to a self-cleaning ink jet printer and methods for cleaning the same, and more particularly to a rotating disk cleaning assembly for an ink jet printer having a fixed canopy-type gutter.
BACKGROUND OF THE INVENTION
An ink jet printer produces images by ejecting ink droplets onto a receiver medium in an image-wise fashion. The advantages of non-impact, low-noise, low energy use, and low cost operation in addition to the capability of the printer to print on plain paper mediums are largely responsible for the wide acceptance of ink jet printers in the marketplace.
“On demand” ink jet printers utilize a pressurization actuator to produce the ink jet droplet at orifices of a print head. In this regard, either one of two types of actuators may be used including heat actuators and piezoelectric actuators. With heat actuators, a heater placed at a convenient location heats the ink and a quantity of the ink will phase change into a gaseous steam bubble and raise the internal ink pressure sufficiently for an ink droplet to be expelled onto the recording medium. With respect to piezoelectric actuators, a piezoelectric material possessing properties such that an electric field is produced when a mechanical stress is applied. The converse also holds true; that is, an applied electric field will produce a mechanical stress in the material. Some naturally occurring materials possessing these characteristics are quartz and tourmaline. The most commonly produced piezoelectric ceramics are lead zirconate titanate, barium titanate, lead titanate, and lead metaniobate.
In the case of “continuous” ink jet printers, electrostatic charging tunnels are placed close to the point where ink droplets are being ejected in the form of a stream. Selected droplets are electrically charged by the charging tunnels. The charged droplets are deflected downstream by the presence of deflector plates that have a predetermined electric potential difference between them. A gutter may be used to intercept the charged droplets, while the uncharged droplets are free to strike the recording medium.
Recently a new type of continuous ink jet printer has been disclosed. U.S. Pat. Nos. 6,079,821 and 6,234,620 issued to Chwalek et al. and Faisst, Jr. et al., respectively, describe a continuous ink jet printer in which on demand asymmetric heating of an ink jet causes selected drops to deflect. In one mode of operation, selected drops are deflected toward an image-recording medium while the other drops are intercepted in a canopy-type gutter that is placed in close proximity (for example, 3 mm) to the ink jet nozzle plate.
Inks for high-speed ink jet printers, whether of the “continuous” or “piezoelectric” type, must have a number of special characteristics. For example, the ink should incorporate a nondrying characteristic, so that drying of ink in the ink ejection chamber is hindered or slowed to such a state that by occasional spitting of ink droplets, the cavities and corresponding nozzles are kept open. The addition of glycol facilitates free flow of ink through the ink jet chamber. Of course, the ink jet print head is exposed to the environment where the ink jet printing occurs. Thus, the previously mentioned nozzles are exposed to many kinds of air born particulates. Particulate debris may accumulate on surfaces formed around the nozzles and may accumulate in the nozzles and chambers themselves. That is, the ink may combine with such particulate debris to form an interference burr that blocks the nozzle or that alters surface wetting to inhibit proper formation of the ink droplet. The particulate debris should be cleaned from the surface and nozzle to restore proper droplet formation. In the prior art, this cleaning is commonly accomplished by brushing, wiping, spraying, vacuum suction, and/or spitting of ink through the nozzle.
Thus, ink jet printers can be said to have the following problems: the inks tend to dry-out in and around the nozzles resulting in clogging of the nozzles; and the wiping of the nozzle plate causes wear on plate and wiper, the wiper itself producing particles that clog the nozzle. In addition, cleaning an ink jet nozzle plate that has limited accessibility due to the placement of a fixed gutter poses extra demands on the design of cleaning members and on methods used.
Ink jet print head cleaners are known. For example, a print head wiping system for ink jet print heads is disclosed in U.S. Pat. No. 5,614,930, entitled “Orthogonal Rotary Wiping System For Ink jet Printheads” issued Mar. 25, 1997 in the name of William S. Osborne et al. The Osborne et al. patent discloses a rotary service station, which incorporates a wiper-supporting tumbler. The tumbler rotates to wipe the print head along a length of a linearly aligned nozzle. In addition, a wiper scraping system scrapes the wipers to clean the wipers. However, Osborne et al. do not disclose use of an external solvent to assist cleaning and also does not disclose complete removal of the external solvent. In addition, a wiper scraping system is limited by the size constraints imposed by the print head itself. This is particularly true for fixed gutter ink jet print head systems, which partially encloses the print head surfaces. Fixed gutter systems require a mechanism that can work within small tolerances imposed by the integrated gutter in order to clean the print head. The Osborne et al. cannot tolerate the stresses demanded by the tight spacing and limited size of current ink jet print heads.
Therefore, there is a need to provide a suitable ink jet printer with a cleaning mechanism, and method of assembling the same, wherein the cleaning mechanism is capable of cleaning the print head surface within the confines of small tolerances and limited spacing. There is also a need to supply cleaning liquid to lubricate and aid cleaning in a manner that does not cause wear of the print head nozzle plate. Furthermore, there is a need for a cleaning mechanism that can operate within the limited spacing imposed by an fixed canopy-type gutter.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a self-cleaning ink jet printer with a cleaning mechanism and method of assembling the same, wherein a surface of a print head belonging to the printer is effectively cleaned.
It is another object of the present invention to provide an ink jet print head assembly that includes a cleaning mechanism and method of assembling the same that can be utilized in fixed gutter continuous ink jet printers.
With the above objects in view, disclosed is a cleaning mechanism composed of a rotating disk cleaning assembly for use in a self-cleaning printer. The self-cleaning printer includes a print head having a print head surface and an ink channel therein, and a structural member that functions as a gutter for collecting ink disposed opposite to the print head surface. The cleaning mechanism is adapted to clean contaminant from the print head surface.
According to an exemplary embodiment of the present invention, a self-cleaning printer is disclosed, wherein the self-cleaning printer includes a print head defining a plurality of ink channels therein, each ink channel terminating in a nozzle. The print head also has a surface thereon surrounding all the nozzles. The print head is capable of jetting ink through the nozzles, such that ink jets are subsequently heated to cause ink drops to form and to selectively deviate for printing. Ink drops are intercepted by either a receiver or a gutter. In one method of operation, ink is selectively deflected onto a receiver (e.g., paper or transparency) supported by a platen disposed adjacent the print head, while the non-deflected ink drops are intercepted by the gutter.
Ink intercepted by the gutter may be recycled. Contaminant such as an oily film-like deposit or particulate matter may reside on the surface and may completely or partially obstruct the nozzle. The oily film may be, for example, grease and the particulate matter may be particles of dirt, dust, metal and/or encrustations of dried ink. Presence of the contaminant interferes with proper ejection of the ink droplets from their respective nozzles and therefore may give rise to undesirable image artifacts, such as banding. It is therefore desirable to clean the contaminant from the surface and the nozzles.
Therefore, a cleaning mechanism is disposed relative to the surface and/or the nozzle, such that a flow of cleaning liquid may be directed along the surface and/or across the nozzle. The cleaning mechanism is disposed relative to the surface and/or the nozzle so as to direct a rotating disk cleaning assembly to clean the contaminant from the surface and/or nozzle via contact with the rotating disk cleaning assembly. As described in detail herein, ink delivered by the print head may be used as cleaning liquid. Ink squirted onto to the rotating disk is used to facilitate and augment cleaning by the rotating disk cleaning assembly. The rotating disk rotates by the rotating action of the internal rotating member, which in turn is connected to a driver that is driven by a motor. The rotating disk is surrounded by a soft and preferably porous covering. The rotating disk and soft covering upon sliding and rotating contact with a print head surface work together to remove contaminants from the print head surface. The soft covering surrounding the rotating disk also serves to hold contaminants and cleaning liquid during cleaning.
In another embodiment, cleaning liquid may be supplied to the print head surface through channels provided in the gutter. In yet another embodiment, the rotating disk cleaning assembly may be combined with an ultrasonic transducer.
A feature of the present invention is the provision of a rotating disk cleaning assembly with channels for liquid that fit in the restricted space between the print head surface and the gutter and is capable removing contaminant from the surface and/or nozzle.
Another feature of the present invention is the provision of a piping circuit to deliver and remove cleaning liquid from the print head surface.
Yet, another feature of the present invention is the provision of a mechanism to align and transport the rotating disk during cleaning operation.
Yet, another feature of the present invention is the provision of an ultrasonic transducer to energize the cleaning action by the rotating disk and the cleaning liquid.
An advantage of the present invention is that the cleaning assembly belonging to the invention cleans the contaminant from the surface and/or nozzle in the confined space between the print head surface and the fixed gutter.
These and other objects, features and advantages of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description taken in conjunction with the appended drawings which show and describe illustrative embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter of the present invention, it is believed the invention will be better understood from the following detailed description taken in junction with the accompanying drawings wherein:
FIG. 1A
is a simplified block schematic diagram of a first embodiment printer system equipped with a page width print head with fixed gutter and cleaning mechanism disposed adjacent to the print head;
FIG. 1B
is a simplified block schematic diagram of a first embodiment printer, the printer equipped with a reciprocating print head with fixed gutter and cleaning mechanism disposed adjacent to the print head;
FIG. 2
is an isotropic view of the print head with fixed gutter, the print head defining a plurality of channels therein, each channel terminating in a nozzle;
FIG. 3
is a side view of a print head according to the invention, showing deflected ink drops directed toward a receiving medium and non-deflected ink drops intercepted by the fixed gutter;
FIG. 4
is a fragmented view in cross-section of the print head shown in
FIG. 3
;
FIG. 5
is a fragmented view in cross-section of a contaminated print head with schematic representation of misaligned ink drops due to contamination;
FIG. 6
is a perspective view of a rotating disk cleaning assembly having a rotating disk and shaft for removing contaminant from a print head surface, in accordance with a preferred embodiment of the present invention;
FIG. 7
is a simplified block schematic diagram of a second embodiment printer system equipped with a page width print head with fixed gutter and rotating disk cleaning assembly disposed adjacent to the print head;
FIG. 8
is a simplified block schematic diagram of a third embodiment printer equipped with a reciprocating print head with fixed gutter and cleaning mechanism disposed on the same block as print head;
FIG. 9
shows an isometric view of print head with a rotating disk cleaning assembly aligned for widthwise translation;
FIG. 10
is a simplified block schematic diagram of a fourth embodiment printer system equipped with a modified gutter for facilitating the flow of a cleaning liquid onto the rotating disk; and
FIG. 11
is a side view of a print head with a modified gutter according to the fourth embodiment printer system shown in FIG.
10
.
Numerals and parts in the detailed description correspond to like references in the figures unless otherwise indicated.
DETAILED DESCRIPTION OF THE INVENTION
The present description will be directed in particular to elements forming part of, or cooperating more directly with, apparatus in accordance with the present invention. It is to be understood that elements not specifically shown or described may take various forms well known to those skilled in the art.
Therefore, referring to
FIGS. 1A and 1B
, therein are shown first and second examples of a first embodiment self-cleaning printer system denoted generally as
400
and
410
, respectively, according to the invention. The self-cleaning printer systems
400
and
410
utilize an image source
10
, such as a scanner or a computer, that provides the raster image data, outline image data in the form of a page description language, or other forms of digital image data. The image source
10
is converted to half-toned bitmap image data by an image-processing unit
12
, which stores the image data in memory. A plurality of heater control circuits
14
read the data from memory within the image-processing unit
12
and apply time-varying electrical pulses to a set of nozzle heaters
50
that are part of a print head
16
. The action of the nozzle heaters
50
(shown in
FIGS. 4 and 5
) and print head
16
during printing is shown in
FIG. 3
wherein the electrical pulses are applied at an appropriate time, and to the appropriate nozzle, so that drops
23
form a continuous ink jet stream to create spots on a recording medium
18
, typically paper, in an appropriate position designated by the data in the memory of the image processing unit
12
. Non-deflected ink drops
21
formed in the non-printing area are intercepted by a gutter
17
, which is fixed in relation to the print head
16
.
Referring to
FIGS. 1A and 1B
, recording medium
18
is moved relative to the print head
16
by a recording medium transport system
20
, which is electronically controlled by a paper transport control system
22
, and which, in turn, is controlled by a micro-controller
24
. The paper medium transport system
22
shown in
FIGS. 1A and 1B
is shown in schematic form only, and many different mechanical configurations are possible, as is known to those of skill in the art. For example, a transfer roller could be used as a paper medium transport system
22
to facilitate transfer of the ink drops
23
to recording medium
18
. Such transfer roller technology is well known in the art. In the case of page width print heads, it is most convenient to move the recording medium
18
past a stationary print head. However, in the case of a scanning print system (as shown schematically in FIG.
1
B), it is usually most convenient to move the print head along one axis (the sub-scanning direction) and the recording medium
18
along an orthogonal axis (the main scanning direction) in a relative raster motion.
Referring to
FIGS. 1A
,
1
B,
3
and
4
, ink is contained in an ink reservoir
28
under pressure. In the non printing state, continuous ink jet drop streams are unable to reach the recording medium
18
due to the position of gutter
17
that blocks the stream to allow a portion of the ink to be recycled by an ink recycling unit
19
. The ink-recycling unit
19
reconditions the ink and feeds it back to ink reservoir
28
. Such ink recycling units are well known in the art. The ink pressure suitable for optimal operation will depend on a number of factors, including geometry and thermal properties of the nozzles and thermal properties of the ink. A constant ink pressure can be achieved by applying pressure to ink reservoir
28
under the control of ink pressure regulator
26
.
The ink is distributed to the back surface of the print head
16
by an ink channel device
30
and through ink channel
31
, as shown in FIG.
4
. The ink preferably flows through slots and/or holes etched through silicon substrate of print head
16
to its print head surface
15
, where a plurality of nozzles
25
and heaters
50
are situated.
FIG. 2
is an isotropic view of the print head
16
and gutter
17
. With print head
16
fabricated from silicon, it is possible to integrate heater control circuits
14
with the print head
16
. In operation, non-deflected ink drops
21
are intercepted by gutter
17
, while deflected ink drops
23
land on the recording medium
18
. Deflection may be caused by a variety of methods including the asymmetric heating method discussed in U.S. Pat. No. 6,079,821 issued to Chwalek et al.
Turning now to
FIG. 5
, it has been observed that the print head surface
15
may become fouled by contaminant
55
. Contaminant
55
may be, for example, an oily film or particulate matter residing on the surface of print head surface
15
. Contaminant
55
also may partially or completely obstructs one or more of the plurality of nozzles
25
. The particulate matter may be, for example, particles of dirt, dust, metal and/or encrustations of dried ink. The oily film may be, for example, grease or the like. Presence of contaminant
55
is undesirable because when contaminant
55
completely obstructs one or more of the plurality of nozzles
25
, ink is prevented from being ejected from nozzle
25
. In this regard, the terms “nozzle” and “nozzles” are used interchangeably throughout either in the singular or plural as may be appropriate.
In addition, when contaminant
55
partially obstructs nozzle
25
, flight of ink droplets
60
may be diverted from first axis
63
to travel along a second axis
65
(as shown). If ink droplets
60
travels along second axis
65
, ink droplets
60
will land on recording medium
18
in an unintended location. In this manner, such complete or partial obstruction of nozzle
25
leads to printing artifacts such as “banding”, a highly undesirable result. A similar printing artifact results if non-selected drops
21
travel on third axis
66
. Also, the presence of contaminant
55
may alter surface wetting and inhibit proper formation of droplets
60
. Therefore, it is desirable to clean (i.e., remove) contaminant
55
to avoid these and other printing artifacts.
Therefore, the self-cleaning printer systems
400
and
410
are equipped with a cleaning mechanism
140
that can be used for simultaneously removing contaminant
55
from the print head surface
15
of the print head
16
and the nozzles
25
, according to the invention. In particular, the self-cleaning printer system
400
of
FIG. 1A
is of the page width print head variety, while self-cleaning printer system
410
of
FIG. 1B
illustrates a scanning type print head. The differences between a page width print head and a scanning type print head are well understood by those of ordinary skill. The cleaning mechanism
140
includes a rotating disk cleaning assembly
32
, disposed for directing cleaning liquid
300
carried in or on a soft absorbent covering
195
on disk
190
to surface
15
and nozzles
25
. Disk
190
moves along the print head surface
15
and across nozzles
25
to clean contaminant
55
therefrom. Disk
190
may be constructed of a soft absorbent material such as felt, polyurethane sponge or expanded polytetrafluroethylene so that cleaning liquid supplied to it is absorbed by the soft absorbent covering. During cleaning, cleaning liquid
300
in or on soft absorbent covering
195
provides chemical cleaning and lubrication between disk
190
and print head surface
15
. Alternatively, disk
190
may be constructed of a stiff material such as plastic or metal coated with soft absorbent material
195
. The stiff material
193
is perforated to allow cleaning liquid
300
supplied to it to wick through and get absorbed by soft absorbent covering
195
. The cleaning liquid
300
mentioned hereinabove may be any suitable liquid solvent composition, such as ink, water, isopropanol, diethylene glycol, diethylene glycol monobutyl ether, octane, acids and bases, surfactant solutions and any combination thereof. Complex liquid compositions may also be used, such as microemulsions, micellar surfactant solutions, vesicles and solid particles dispersed in the cleaning liquid
300
.
To better understand the implementation of print head cleaning assembly
32
and, in particular, the disk
190
, reference is made to FIG.
6
.
FIG. 6
is a perspective view of a section of rotating disk cleaning assembly
32
having a disk
190
and a shaft
191
for removing contaminant from a print head surface
15
, in accordance with a preferred embodiment of the present invention. The disk
190
can be constructed by laminating a perforated metal or plastic disk
193
with a soft absorbent material
195
. Arrow
604
indicates the motion of disk
190
when driven by a motor (not shown) coupled to shaft
191
. In first embodiment self-cleaning printer systems
400
and
410
, cleaning liquid is supplied to the absorbent covering
195
through channels (not shown) in cleaning assembly block
180
prior to engagement of disk
190
with print head surface
15
.
In operation, upon receiving an electronic signal from micro-controller
24
via cleaning assembly control
40
, pump
36
is activated causing cleaning liquid
300
to be moved from cleaning liquid reservoir
270
through filter
280
and sprayed onto surface of disk
190
. Cleaning assembly control
40
also activates disk motor (not shown) causing the disk
190
to rotate. Micro-controller
24
also sends as electronic signal to print head transport control
42
, which causes print head
16
to assume a “maintenance” position by translating toward disk
190
following the direction of arrow
44
a
. Preferably, disk
190
is pre-aligned with print head surface
15
of print head
16
so that when print head
16
reaches disk
190
, print head surface
15
and nozzles
25
are in contact with soft absorbent material
195
of disk
190
. Thus, as print head
16
continues to travel along direction of arrow
44
a
, contaminant
55
on print head surface
15
and in nozzles
25
is removed by the disk
190
. After cleaning, print head
16
is translated back along direction of arrow
44
b
to its normal printing position.
As can be appreciated by those of ordinary skill, the process of engaging disk
190
with print head surface
15
described above is one of many methods of using cleaning assembly
32
to clean print head surface
15
and nozzles
25
. For example rather than having print head surface
15
moved towards disk
190
, cleaning assembly
32
may be optionally equipped with its own translation capability wherein the cleaning assembly
32
moves from a “home” position to a cleaning position that enables the disk
190
to come into contact with the print head surface
15
.
Referring to
FIG. 7
, therein is shown an example of self cleaning ink jet printer system, denoted generally as
420
in which cleaning assembly
32
may be translated for the purpose of cleaning print head surface
15
and nozzles
25
of print head
16
. By way of example only, print head cleaning assembly
32
may be supported on an elevator (not shown) and lifted in direction of arrow
46
b
to appropriate location in order to engage the disk
190
with print head surface
15
of print head
16
. This corresponds to the cleaning position of the cleaning assembly
32
. Similarly, translation of cleaning assembly
32
along arrows
70
a
and 70
b
may also be utilized to aid optimal engagement of disk
190
with print head surface
15
of print head
16
. After print head surface
15
and nozzles
25
have been cleaned, print head
16
is translated back to its printing position, and print head cleaning assembly
32
is lowered to its rest or home position along arrow
46
a.
When required, disk
190
may be replaced or cleaned. Disk
190
may be cleaned using cleaning liquid supply to cleaning assembly block
180
. For example, cleaning liquid
300
may be suctioned from the cleaning liquid reservoir
270
and directed through piping segment
38
a
and squirted onto disk
190
during cleaning. Used cleaning liquid can be returned to cleaning liquid reservoir
270
via piping segment
38
b
. Alternatively, a mechanism (not shown) may be provided to lower disk
190
so that it is in contact with vacuum slots (not shown) provided in cleaning assembly block
180
. Cleaning liquid
300
supplied to disk
190
by pump
36
may now be sucked away by vacuum pump
34
.
Referring to
FIGS. 8 and 9
therein is shown an example of a third embodiment self cleaning ink jet printer system, denoted generally as
430
, in which a print head cleaning assembly
33
is provided on the same block as print head
16
. In order to clean print head surface
15
and nozzles
25
, disk
190
translates back and forth on guide rail
77
following arrows
75
a
and
75
b
. According to the third embodiment of printer system
430
, rotating disk cleaning assembly
33
is mounted on print head
16
and pre-aligned with surface
15
and gutter
17
. Upon receiving an appropriate electrical signal from cleaning assembly controller
40
and micro-controller
24
, rotating disk cleaning assembly
33
is activated to translate along the direction of seventh arrow
75
a
using guide rail
77
, as shown in FIG.
9
. The motor driving the rotating disk cleaning assembly
33
is not shown.
As before, disk
190
is covered with a soft absorbent material
195
and may be cleaned on pad
90
. Cleaning liquid
300
is supplied via duct
500
and recycled through duct
510
. Further more, a separate duct (not shown) may be provided to supply vacuum suction to disk
190
during cleaning.
Referring to
FIGS. 10 and 11
therein is shown an example of a fourth embodiment self cleaning ink jet printer system
440
capable of removing contaminant
55
from surface
15
and nozzles
25
. In particular, ink jet printer system
440
has a disk
190
that is supplied with cleaning liquid
300
through modified gutter
17
a
. Cleaning liquid
300
is pumped to modified gutter
17
a
through valve
520
and piping segment
530
by pump
36
. To facilitate the flow of cleaning liquid, modified gutter
17
a
has an internal duct
85
, which delivers cleaning liquid
300
onto a soft absorbent covering
195
on the disk
190
. Delivery of cleaning liquid through modified gutter
17
a
is compatible with previously discussed self cleaning printer systems, i.e., modified gutter
17
a
, valve
520
and piping segment
530
may readily be added to self cleaning printer systems
400
,
410
,
420
and
430
.
While the invention has been described with particular reference to its preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements of the preferred embodiments without departing from the invention. For example, it will be appreciated that
FIGS. 7
,
8
,
9
, and
11
depict a page width print head by way of example only. Scanning type print heads that are smaller than page width size can also be cleaned using a variation of the method described above. In yet another variation, rather that use a cleaning liquid
300
for cleaning print head surface
15
and nozzles
25
of print head
16
, ink
29
may be squirted out of nozzles
25
on to soft absorbent covering
195
on disk
190
during cleaning. At the end of the cleaning cycle, disk
190
and soft absorbent covering
195
may be cleaned with cleaning liquid
300
by the methods described above. In yet another variation, cleaning assemblies
32
and
33
may be coupled to an ultrasonic transducer to enhance cleaning of print head print head surface
15
and nozzles
25
. In addition, many modifications may be made to adapt a particular situation and material to a teaching of the present invention without departing from the essential teachings of the invention.
|
PARTS LIST
|
|
|
10
image source
|
12
image processing unit
|
14
heater control circuits
|
15
front surface
|
16
print head
|
17
gutter
|
17a
modified gutter
|
18
recording medium
|
19
ink recycling unit
|
20
recording medium transport system
|
21
non-deflected ink drop
|
22
recording medium transport control system
|
23
deflected ink drop
|
24
micro-controller
|
25
nozzle
|
26
ink pressure regulator
|
28
ink reservoir
|
29
ink
|
30
ink channel device
|
31
ink channel
|
32
rotating disk cleaning assembly
|
33
rotating disk cleaning assembly on print head
|
34
vacuum pump
|
36
circulation pump
|
38a
piping segment
|
38b
piping segment
|
40
cleaning assembly motion control
|
42
cleaning assembly motion control
|
44a
first arrow
|
44b
second arrow
|
6a
third arrow
|
46b
fourth arrow
|
50
nozzle heaters
|
55
contaminant
|
60
ink droplet
|
63
first axis
|
65
second axis
|
70a
fifth arrow
|
70b
sixth arrow
|
75a
seventh arrow
|
75b
eighth arrow
|
77
guide rail
|
79a
ninth arrow
|
79b
tenth arrow
|
90
pad
|
180
cleaning assembly block
|
190
rotating disk
|
191
rotating shaft
|
193
perforated metal or plastic disk
|
195
soft absorbent covering
|
300
cleaning liquid
|
400
first embodiment printer system
|
410
second example of first embodiment printer system
|
420
third example of first embodiment printer system
|
430
third embodiment printer system
|
440
fourth embodiment printer system
|
500
supply duct
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510
return duct
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520
control valve
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530
piping segment
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604
arrows
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Claims
- 1. A self-cleaning ink jet printer system, comprising:a print head having a surface thereon; an ink reservoir containing ink; a gutter integrally connected to said print head for intercepting said ink in a non-printing mode; and a rotating disk cleaning assembly for cleaning said print head surface, said rotating disk cleaning assembly including a disk having a planar surface that interacts with said print head surface, said planar surface being flat such that the interaction of said, planar surface with said print head surface remains constant during cleaning.
- 2. The ink jet printer system of claim 1, wherein said rotating disk cleaning assembly comprises:a shaft having an internal rotating member, said internal rotating member of said shaft connected to said disk for coming into direct rotating sliding contact with said print head surface to thereby remove contaminants from said print head surface; and a motor for driving said shaft.
- 3. The ink jet printer system of claim 2, further comprising an absorbent covering surrounding said disk.
- 4. The ink jet printer system of claim 3 further comprising a means for translating said rotating disk cleaning assembly towards said print head surface so that said soft covering touches said print head surface during rotation of said disk thereby permitting contaminants to be removed from said print head surface.
- 5. The ink jet printer system of claim 2, further comprising a cleaning assembly control configured to cause said rotating disk cleaning assembly to assume a cleaning position.
- 6. The ink jet printer system of claim 5, wherein said cleaning assembly control is further configured to cause said rotating disk cleaning assembly to assume a normal printing position after cleaning of said printer head surface.
- 7. The ink jet printer system of claim 2, further comprising a micro-controller configured to send an electronic signal that causes said print head to assume a maintenance position wherein said print head surface is translated towards said rotating disk cleaning assembly.
- 8. The ink jet printer system of claim 2, further comprising a block supporting said print head and wherein said rotating disk cleaning assembly is mounted on said block adjacent said print head.
- 9. The ink jet printer system of claim 8, further comprising a guide rail configured to permit said disk to translate along an areas spanned by said print head surface.
- 10. The ink jet printer system of claim 2, wherein said rotating disk cleaning assembly is mounted on said print head and pre-aligned with said print head surface.
- 11. The ink jet printer system of claim 1, further comprising a mounting block for supporting said rotating disk cleaning assembly.
- 12. The ink jet printer system of claim 1, further comprising:a reservoir for storing a cleaning liquid; a first piping segment providing a flow channel in a first direction between said reservoir and said rotating disk cleaning assembly; and a pump for directing a cleaning liquid from said reservoir to said rotating disk cleaning assembly via said first piping segment.
- 13. The ink jet printed system of claim 12, further comprising a second piping segment providing a flow channel in a second direction between said reservoir and said rotating disk cleaning assembly so that used cleaning liquid is returned to said cleaning reservoir.
- 14. The ink jet printer system of claim 1, wherein said disk surface is located on a radial surface of said disk.
- 15. A self-cleaning ink jet printer system comprising:a print head having a surface thereon; an ink reservoir containing ink; a gutter integrally connected to said print head for intercepting said ink in a non-printing mode; a rotating disk cleaning assembly for cleaning said print head surface, said rotating disk cleaning assembly including a disk; and an absorbent covering surrounding said disk, wherein said gutter further comprises an internal duct adapted to deliver a cleaning liquid to said absorbent covering.
- 16. A cleaning mechanism for a self-cleaning ink jet printer with a print head having a print head surface containing a plurality of orifices therein, said printer having a gutter integrally connected to said print head for intercepting ink in a non-printing mode, said cleaning assembly comprising:a rotating disk cleaning assembly for cleaning said print head surface, said rotating disk cleaning assembly including a disk having a planar surface that interacts with said printhead surface, said planar surface being flat such that the interaction of said planar surface with said printhead surface remains constant during cleaning; a means for moving, positioning, and aligning said rotating disk cleaning assembly; a means for delivery of a cleaning liquid to said rotating disk cleaning assembly; a vacuum pump to provide suctioning of said cleaning liquid; and a cleaning liquid reservoir, wherein said cleaning liquid is delivered to said rotating disk cleaning assembly by said means for delivery and suctioned back by said vacuum pump so that contaminants are removed from said print head surface through the suctioning action of said vacuum pump before being discharged into said cleaning liquid reservoir.
- 17. The cleaning mechanism of claim 16, wherein said rotating disk cleaning assembly further comprises:a shaft connected to said disk for coming into direct contact with said print head to thereby remove contaminants from said print head surface; and a motor for driving said shaft.
- 18. The cleaning mechanism of claim 17, wherein said disk is surrounded by an absorbent covering that upon contact with said print head surface permits contaminants to be removed.
- 19. The cleaning mechanism of claim 16, further comprising a pump configured to assist in delivering cleaning liquid from said cleaning liquid reservoir to said rotating disk cleaning assembly.
- 20. The cleaning mechanism of claim 16, further comprising an ultrasonic transducer configured to assist in delivering cleaning liquid from said cleaning liquid reservoir to said rotating disk cleaning assembly.
- 21. The cleaning mechanism of claim 16 wherein said rotating disk cleaning assembly is mounted to said print head.
- 22. A cleaning mechanism for a self-cleaning ink jet printer with a print head having a print head surface containing a plurality of orifices therein, said printer having a gutter integrally connected to said print head for intercepting ink in a non-printing mode, said cleaning assembly comprising:a rotating disk cleaning assembly for cleaning said print head surface; a means for moving, positioning, and aligning said rotating disk cleaning assembly; a means for delivery of a cleaning liquid to said rotating disk cleaning assembly; a vacuum pump to provide suctioning of said cleaning liquid; and a cleaning liquid reservoir, wherein said cleaning liquid is delivered to said rotating disk cleaning assembly by said means for delivery and suctioned back by said vacuum pump so that contaminants are removed from said print head surface through the suctioning action of said vacuum pump before being discharged into said cleaning liquid reservoir and said means for delivery comprises an internal duct in said gutter.
- 23. In a self-cleaning ink jet printer, a method for cleaning an ink jet printer head having a print head surface thereon, said ink jet printer including a fixed gutter assembly, a rotating disk cleaning assembly for removing contaminants from said print head surface and a controller, said method comprising the steps of:(a) translating said rotating disk cleaning assembly from a pre-defined home position to a cleaning position; (b) causing said rotating disk cleaning assembly to come in contact with said print head surface and remove contaminants therefrom, said rotating disk cleaning assembly including a disk having a planar surface that interacts with said printhead surface, said planar surface being flat such that the interaction of said planar surface with said printhead surface remains constant during cleaning; and (c) translating said rotating disk cleaning assembly from said cleaning position to said defined home position.
- 24. The method of claim 23 further comprising the step of translating said print head to pre-defined maintenance position prior to said step of translating said rotating disk cleaning assembly to said cleaning position.
- 25. The method of claim 24 further comprising the step of translating said print head to a pre-defined printing position following said step of translating said rotating disk cleaning assembly from said cleaning position to said defined home position.
- 26. In a self-cleaning ink jet printer, a method for cleaning an ink jet printer head having a print head surface thereon, said ink jet printer including a fixed gutter assembly, a rotating disk cleaning assembly for removing contaminants from said print head surface and a controller, said method comprising the steps of:translating said rotating disk cleaning assembly from a pre-defined home position to a cleaning position; causing said rotating disk cleaning assembly to come in contact with said print head surface and moving said rotating disk cleaning assembly at a pre-determined speed and for a pre-determined distance in order to avoid colliding with said fixed gutter assembly; and translating said rotating disk cleaning assembly from said cleaning position to said defined home position.
US Referenced Citations (9)
Foreign Referenced Citations (6)
Number |
Date |
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Jul 1982 |
DE |
3042998 |
Jan 1982 |
DK |
0988978 |
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EP |
988978 |
Mar 2000 |
EP |
63022656 |
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JP |
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Jan 1994 |
JP |