EP0481829A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
High definition thermal ink-jet printer
Assignee: HP Inc
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Filing: 1991-10-21
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Granted: —
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Expires: 2011-10-21
Abstract
Abstract A thermal ink-jet printer (10) including a paper advancing mechanism (14) and a pen traversing mechanism (18) and a pen (20) is disclosed. The pen (20) includes a nozzle plate portion (22) which includes irregularly spaced columns of nozzles (24) for staggering application of inks onto the print medium (16) such that a drying time is provided between applications of differing inks to adjacent areas. The printer (10) further includes a platen heater assembly (68) as a means of fixing and drying the ink on the print medium (16), and a vacuum fan (62) and an associated plurality of platen vacuum holes (74) as a means of holding the print medium (16) in close contact with the heater plate assembly (68), thus increasing efficiency of heat transfer. The printer (10) is characterized in that it is capable of producing, at relatively high speeds on ordinary untreated paper or other print medium, a highly defined image relatively free from the problems of color bleeding, feathering, ink coalescence, and paper cockle normally associated with ink-jet printers. The primary usage of the printer (10) is in computer generated data printout applications.
Inventors
- 👤 Michael Anh Nguyen
- 👤 Kent Douglas Vincent
- 👤 John Phillip Ertel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 06:16
CPC Classifications
B; B41; B41J; B41J11/00; B41J11/0085; B41J11/0015; B41J11/002; B41J11/0024; B41J11/00242; B41J11/00244; B41J2/00; B41J2/005; B41J2/01; B41J2/21; B41J2/2103; B41J29/00; B41J29/377
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
115 words
An ink-jet printer comprising in associative combination: (a) a paper traction means rigidly affixed to a printer body for moving a medium to be printed upon in a medium advancement direction; (b) a printhead for printing on said medium, mounted on a printhead carriage, said printhead carriage being rigidly affixed to said printer body and adapted for holding said printhead such that said printhead can be moved orthogonally relative to said medium advancement direction; and (c) a platen heater for heating said medium, said platen heater being rigidly affixed to said printer body adjacent to said printhead such that said medium is drawn between said printhead and said platen heater by said paper traction means.
Claim 2
Dependent Claim
34 words
The ink-jet printer of Claim 1, wherein: said platen heater is constructed from a low heat capacity metal alloy plate and includes a thin foil heating element rigidly affixed to said metal alloy plate.
Claim 3
Dependent Claim
15 words
The ink-jet printer of Claim 2, wherein: said platen heater includes a low emissivity surface.
Claim 4
Dependent Claim
32 words
The ink-jet printer of Claim 1, wherein: said heating element is adjustable so as to provide an adjustable temperature in said metal plate and to maintain the set temperature within set limits.
Claim 5
Dependent Claim
118 words
The ink-jet printer of Claim 1, wherein: said printhead includes a nozzle plate having a plurality of nozzles arranged into a plurality of nozzle groups such that each of said nozzle groups is provided with a different color of ink and further wherein each of said nozzle groups is separated by a group separation span, said group separation span being greater than a nozzle separation span, said nozzle separation span being the distance between the nozzles within each of said nozzle groups; such that as said printhead traverses across said medium, each of said nozzle groups can print a swath across said print medium, said swaths being separated by a distance substantially equal to said group separation span.
Claim 6
Dependent Claim
36 words
The ink-jet printer of Claim 5 having a data offset from one color to an adjacent color equivalent to the number of nozzles of a color band plus the nozzle equivalent of said group separation span.
Claim 7
Dependent Claim
132 words
An ink-jet printer comprising in associative combination: (a) a paper traction means rigidly affixed to a printer body for moving a medium to be printed upon in a medium advancement direction; (b) a printhead for printing on said medium, mounted on a printhead carriage, said printhead carriage being rigidly affixed to said printer body and adapted for holding said printhead such that said printhead can be moved orthogonally relative to said medium advancement direction; (c) a platen heater for heating said medium, said platen heater being rigidly affixed to said printer body adjacent to said printhead such that said medium is drawn between the said printhead and said platen heater by said paper traction means; and (d) a medium holding means for holding said print medium in contact with said platen heater.
Claim 8
Dependent Claim
84 words
The ink-jet printer of Claim 7, wherein said medium holding means includes: (a) a vacuum chamber located adjacent to said platen heater on a side opposite said print medium; (b) a vacuum-generating means mounted in a first panel of said vacuum chamber for creating a partial vacuum within said vacuum chamber; and (c) a plurality of holes in a second panel of said vacuum chamber adjacent to said platen heater for exposing said print medium to the partial vacuum created by said vacuum-generating means.
Claim 9
Dependent Claim
24 words
The ink-jet printer of Claim 8, wherein said medium holding means further includes: means to mechanically press said print medium against said platen heater.
Claim 10
Dependent Claim
34 words
The ink-jet printer of Claim 8, wherein: said platen heater is constructed from a low heat capacity metal alloy plate and includes a thin foil heating element rigidly affixed to said metal alloy plate.
Claim 11
Dependent Claim
33 words
The ink-jet printer of Claim 10, wherein: said platen heater is mounted in an opening in said vacuum chamber, and said holes are placed in said metal alloy plate of said platen heater.
Claim 12
Dependent Claim
15 words
The ink-jet printer of Claim 10, wherein: said platen heater includes a low emissivity surface.
Claim 13
Dependent Claim
32 words
The ink-jet printer of Claim 7, wherein: said heating element is adjustable so as to provide an adjustable temperature in said metal plate and to maintain the set temperature within set limits.
Claim 14
Dependent Claim
118 words
The ink-jet printer of Claim 7, wherein: said printhead includes a nozzle plate having a plurality of nozzles arranged into a plurality of nozzle groups such that each of said nozzle groups is provided with a different color of ink and further wherein each of said nozzle groups is separated by a group separation span, said group separation span being greater than a nozzle separation span, said nozzle separation span being the distance between the nozzles within each of said nozzle groups; such that as said printhead traverses across the medium, each of said nozzle groups can print a swath across said print medium, said swaths being separated by a distance substantially equal to said group separation span.
Claim 15
Dependent Claim
36 words
The ink-jet printer of Claim 14 having a data offset from one color to an adjacent color equivalent to the number of nozzles of a color band plus the nozzle equivalent of said group separation span.
Claim 16
Dependent Claim
118 words
An ink-jet printer for depositing ink upon a print medium, including: a printhead pen using more than one color of ink, said printhead being movably affixed to said printer such that it can be moved under computer control across a print medium, disbursing ink as required upon said medium, said printhead having a nozzle plate adapted for ejecting ink from said printhead onto said print medium, said nozzle plate including a plurality of nozzles arranged in a column with the nozzles which are to supply like colors separated into a plurality of groups of nozzles such that the nozzles for different color inks are physically separated by a greater distance than are nozzles for the same color ink.
Claim 17
Dependent Claim
33 words
The ink-jet printer of Claim 16, wherein: the spacings between adjacent nozzle centers for different ink colors is an integer multiple of the distance between adjacent nozzle centers for the same color ink.
Claim 18
Dependent Claim
21 words
The ink-jet printer of Claim 16, wherein the nozzles of a given color group are separated by an integer nozzle spacing.
Claim 19
Dependent Claim
36 words
The ink-jet printer of Claim 18, wherein the spacing between adjacent nozzle centers for ink colors within the same color group is an integer multiple of the distance between adjacent nozzle centers for that color group.
Claim 20
Dependent Claim
29 words
The ink-jet printer of Claim 16, wherein the column into which the nozzles is arranged is a staggered column with alternate of the nozzles aligned and consecutive nozzles non-aligned.
Claim 21
Dependent Claim
126 words
The ink-jet printer of Claim 16, and further including: means for advancing said print medium past said printhead after each swath of said printhead, said means adapted to advance said medium by a medium advance span which is the length of a portion of the column of nozzles which includes all of the nozzles associated with one color, and wherein data sent to the columns of nozzles associated with successive color bands is delayed relative to the data that is fed to the immediately preceding column of nozzles by a number of index lines equal to the number of nozzles in a column associated with one color ink plus a number of index lines equivalent to the space between columns of nozzles associated with different colors.
Claim 22
Dependent Claim
36 words
The ink-jet printer of Claim 16, and further including: a platen heater positioned adjacent to said print medium and opposing said printhead such that said print medium is drawn between said platen heater and said printhead.
Claim 23
Dependent Claim
100 words
The ink-jet printer of Claim 22, and further including: (a) a vacuum-creating means for producing a partial vacuum behind said platen heater, said vacuum-creating means being affixed to said ink-jet printer such that a partial vacuum is formed in a cavity behind said platen heater on a side of said platen heater opposite said print medium; and (b) a plurality of holes in said platen heater positioned to expose said print medium to the partial vacuum such that said print medium is held against said platen heater for efficient transfer of heat from said platen heater to said print medium.
Claim 24
Dependent Claim
34 words
The ink-jet printer of Claim 23, and further including: means to mechanically press said print medium against said platen heater to maximize the conduction of heat from said platen heater to said print medium.
Claim 25
Dependent Claim
50 words
The ink-jet printer of Claim 22, wherein: said platen heater further is extended into a preheating area, said preheating area being the area over which said print medium passes just prior to its being printed upon, such that said print medium is already heated prior to application of ink thereto.
Claim 26
Dependent Claim
53 words
The ink-jet printer of Claim 22, wherein: said platen heater further is extended into a post-heating area, said post-heating area being the area over which said print medium passes just after it is printed upon, such that said print medium continues to be heated by said platen heater even after it is printed-upon.
Claim 27
Dependent Claim
124 words
An ink-jet pen for use in an ink-jet printer for depositing ink upon a print medium, including: a printhead pen using more than one color of ink, said printhead being movably affixed to said printer such that it can be moved under computer control across said print medium, disbursing ink as required upon said medium, said printhead having a nozzle plate adapted for ejecting ink from said printhead onto said print medium, said nozzle plate including a plurality of nozzles arranged in a column, with the nozzles which are to supply like colors separated into a plurality of groups of nozzles such that the nozzles for different color inks are physically separated by a greater distance than are nozzles for the same color ink.
Claim 28
Dependent Claim
33 words
The ink-jet pen of Claim 27, wherein: the spacings between adjacent nozzle centers for different ink colors is an integer multiple of the distance between adjacent nozzle centers for the same color ink.
Claim 29
Dependent Claim
20 words
The ink-jet pen of Claim 27 wherein the nozzles ofa given color group are separated by an integer nozzle spacing.
Claim 30
Dependent Claim
36 words
The ink-jet pen of Claim 29 wherein the spacing between adjacent nozzle centers for ink colors within the same color group is an integer multiple of the distance between adjacent nozzle centers for that color group.
Claim 31
Dependent Claim
29 words
The ink-jet pen of Claim 27, wherein the column into which the nozzles is arranged is a staggered column with alternate of the nozzles aligned and consecutive nozzle misaligned.
Claim 32
Dependent Claim
186 words
In an ink-jet printer process for producing multi-color images wherein printing is accomplished by alternately first passing a printhead having a plurality of nozzles orthogonally across a print medium while causing an plurality of inks to be ejected from said printhead as directed by a controlling computer and then advancing said print medium past said printhead, the improvement to the process comprising the steps of: (a) heating said print medium before it is printed upon in order to preheat said medium such that a solvent component of the ink will volatilize upon contact with said medium; (b) heating said print medium while it is being printed upon in order to dry the ink as quickly as possible, so that the migration of ink on said print medium is minimized; and (c) continuing to heat said print medium after it is printed upon to ensure that the ink is completely dried onto said print medium; with the proviso that, the process described being a continuous process, all of the several above described improvement steps occur substantially simultaneously during the process on sequential sections of said print medium.
Claim 33
Dependent Claim
68 words
The improved process of Claim 32, and further including: (a) applying a partial vacuum to said print medium during said heating steps in order to improve efficiency of heat transfer between said print medium and a heat source; and (b) minimizing the distance between said print medium and said heat source in order to improve the efficiency of heat transfer between said print medium and said heat source.
Claim 34
Dependent Claim
110 words
The improved process of Claim 32, and further including the steps of alternately: (a) applying the inks in a plurality of color bands, each of said color bands being of a different color than a remainder of said color bands, such that each of said color bands is separated by a color band separation span, during each pass of said printhead across said medium; and then (b) advancing said print medium by a print medium advance span which is the width of one of said color bands; said steps being controlled by said controlling computer such that ink is ejected at all locations necessary to form a completed desired image.
Claim 35
Dependent Claim
18 words
The improved process of Claim 32, wherein: the inks are of a low viscosity and quick drying type.
Claim 36
Dependent Claim
25 words
The improved process of Claim 32, wherein: said print medium comprises ordinary paper which has not been specially treated for use with the inventive process.
Claim 37
Dependent Claim
65 words
The improved process of Claim 32, and further including the steps of alternately: (a) applying the inks in a plurality of bands such that each of said bands is separated by a band separation span, during each pass of said printhead across said medium; and (b) advancing said print medium by a print medium advance span which is the width of said band separation span.
References Cited (Backward Citations)
No citation records indexed.
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