CA1191390A - Selective density printing using dot matrix print heads in fixed spatial relation - Google Patents
Selective density printing using dot matrix print heads in fixed spatial relationInfo
- Publication number
- CA1191390A CA1191390A CA000417174A CA417174A CA1191390A CA 1191390 A CA1191390 A CA 1191390A CA 000417174 A CA000417174 A CA 000417174A CA 417174 A CA417174 A CA 417174A CA 1191390 A CA1191390 A CA 1191390A
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- CA
- Canada
- Prior art keywords
- head
- heads
- character
- line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/485—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by the process of building-up characters or image elements applicable to two or more kinds of printing or marking processes
- B41J2/505—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by the process of building-up characters or image elements applicable to two or more kinds of printing or marking processes from an assembly of identical printing elements
- B41J2/515—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by the process of building-up characters or image elements applicable to two or more kinds of printing or marking processes from an assembly of identical printing elements line printer type
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- Printers Characterized By Their Purpose (AREA)
Abstract
SELECTIVE DENSITY PRINTING USING
DOT MATRIX PRINT HEADS IN FIXED
SPATIAL RELATION
Abstract Alternate print heads are misaligned to invoke counterpart density printing by selected heads over-striking a character with misaligned dots falling between previously printed dots to increase print density.
DOT MATRIX PRINT HEADS IN FIXED
SPATIAL RELATION
Abstract Alternate print heads are misaligned to invoke counterpart density printing by selected heads over-striking a character with misaligned dots falling between previously printed dots to increase print density.
Description
~)C9--80~01G
3~
SEI.ECTlVE DENSII'Y PRINTING USING DOT
MATRIX PRINT ~-IEADS IN FIXED SPATIAL RELATION
Technical Field This invention relates to dot ma-trix printers and, more particularly, to selectively varying the dot density and print quality.
Background In order to achieve quality or "pretty" printed characters, one relies upon a relatively smooth character contour in addition to a hiyh contrast (black/white) ratio between character and the recording medium. Where a character is formed on a medium ~rom a matrix of dots produced by a wire matrix print head through a ribbon, the contrast ratio is a functi.on of the dot density. In this regard, character contour or smoothness is a function of the overlap relationship among the dots especially in the vertical direction.
Martin, et al., USP 4,010,835 issued 8 March 1977, describes a wire matrix print head arranged to provide two different printing arrays. In a first embodiment, the print wires are contained in two guides, one of which can be translationally displaced in a vertical direction from the other guide which is held in a fixed position. In a second embodiment, the wires are arranged in a single wire guide rotatable about an axis which is perpendicular to the document and parallel to the print wires. Further, in Martin the print head is translated horizontally from left to right to print across a line on BC9-80-0l6 a document. Printing i.s e:Efected by the impact of se1ectkd plura]ities of print wires, each of which is provided with a separate actuator arranged so that when the actuator is eneryiæed, -the associated print wi.re is driven forwared to impact the paper. An inlced rihbon is interposed between the document (recordinc~ medium) and the print wires. The impact oF the print wi.re on the ribbon causes a do-t to be printed at a selected point on the document. By energizing combinations of actuators, combinations of print wires can be imprinted corresponding to a selected character.
In the prior art, it has been customary to fabricate a single vertical wire column print head with wires bent along a portion of their extent. This bend creates a long wire path subjec-t to breakage and friction. Replacement of wires in such a head is not feasi~le. In contrast, a relatively never-fail print head may be fashioned from wires being laid in a diagonal rather than column array.
Reference should be made to Leontiades, USP
4,284,001, issued 18 August 1981 showing a wire matrix printer having a plurality of print heads in which the wires are positioned in slanted relationship. In this arrangement, it is possible for a slant head to be involved with two or more characters. The overlapping of the slant heads and dotted character matrices creates a complex mapping relationship between both the data points and the print wire matrix.
Choberka, et al., USP 4,284,363, issued 18 August 1981, describes a dot matrix tilting print head assembly in which the print head is rotatably mounted and framed. The dot matrix print head has its wires actuated to cause dots to be printed on the recordiny medium while the BC9-80-0~.6 print head is :Iaterally moved across the medium, the centers o~ the dots being separa-tecl by a given dlstance. In order to :i~prove print quality, there i.s involved the insertion of dots between previously printed dots by controlling the rotation.
The Invention The -technical problem solved by this invention is to vary the density within prin-ted dot matrix characters by selectively overstriking the same mediurn position with the same character or a portion thereof positionally offset in at least one direction without requiring that the medium be moved or complex rotational head motion be involved. The solution involves partitioning each print line extent into several zones and assigning print heads to the counterpart zones; positioning the heads in fixed verti.cal offset relation to each other, and selectively causing each head to imprint the mediurn wi-thin its zone for low density and to overstrike a designated position within ano-ther zone with a predetermined character or portion thereof for high density.
Significantly, the printer includes a plurality of print heads, each posltioned to print a portion of the line and each including a plurality of wires which print dots separated by a given distance.
Corresponding wires of one of the alterna-te print heads is horizontally aligned to print dots between printed dots of the other of the alternate print heads. A
vertical displacement or offset of one-half character dot between overstrik.ing pairs of heads yields aesthetically pleasing dot matrix characters. For low density, the half character dot displacement between the characters in the zones is not readily discernible to the eye. Advantageously, the sc9-80-016 ~ 3~
~1 only mechallical mot:i.on ls the horizonta]. di..spl.acement of the preferably ganged print heads.
Brie:E Summary of the Drawings FIG. 1 is a simplifled system diagram for a dot matrix printer system of the type within which the inven-tion is contained;
FIG. 2 illustrates the printer conso].e inclucling the recording medium propagation path in relation to the print head mechanism;
FIG. 3 is a frontal view of the printer unit in the console shown in FIG. 2;
FIG. 4 illustrates four heads of nine-wire per head printing bloc~;
FIG. 5 depicts the recording medium partiti~ned into prin-t zones;
FIGS. 6 and 7 show the dot distribution in low and high density printing.
Description of the Preferred Embodiment and Industrial Applicability The wire matrix printer is substantially of the type described in Leontiades, USP 4,284,001 issued August 18, 1981.
Referring now to FIG. 1, there is shown a represen~ative system configuration including a host system 1, and a printer system 2. The printer system includes a BC9-~30--Q I 6 3''~
con-trol uni-t 3 and an attachment logic 4. Command and da-ta signals are provldecl by the host system to printer control unit 3 by way of bus 5. Command and control signals are obtalned from printer control unit 3 over the printer adapter 4 by way of bus 6. Status signals are supplled by the printer control unit 3 to host system 1 over bus 5. Typically, the host system applies sequences of commands and data to the printer and monitors status in return. Control unit 3 receives the eommands, decodes them, checks for errors, and generates status information. Control unit 3 further regulates printing and spacing and includes local diagnostics. The adapter 4 executes decoded control unit commands, monitors all printer operations, actuates print wires, drives motors, senses printer emitters, and controls operator panel lights and switching circuitry. Also, the adapter controls the traetors, the ribbon drive, the print head carrier, the operator panel, and the printer sensors. It should be appreciated that the printer control unit 3 and adapter 4 incorporate one or more mieroprocessors for analyzing eommands and data and to regulate operations.
FIGS. 2 and 3 illustrate eomponents of the printer housed in console 10. Aecess panels or covers 11, 12, 13 keep a relatively clean industry environment. Top cover 11 has a window 14 enabling an operator to observe paper path movement during operation of the printer whenever the cover is closed. The recording medium is paper 15. It is obtained from a stored stack 16 and is fed into an upwardly or downwardly transversing paper path as seen in FIGSo 2 and 3 by way of a mechanical assembly 20 which includes one or more sets of tractors 90 and 91. A guide 28 moves the paper after printing to a takeup stack ~not shown) positioned below the printing mechanism and to the rear of the console. The printer incorporates a print assembly 30 which is positioned in a horizontal ~3~3~
relationslli~ with respect to the mecliuln ~5 at;a prillt station 32. The printer ribbon drive assembly 40 is located in closer proximity to the front of the printer.
The printer control unit 3 and its associated micro-processors are situated behind the side cover 13.
A ribbon ~1 is provided on one of the spools ~2 or43. Each ribbon box preferably contains a disposable ribbon shoe ~6 mounted on spring attachment members 130 and 13l between print assembly 30 and the medium 15 in order to maintain rib~on 41 in proper alignment and to minimize ink smudging on the medium. The ribbon moves on a path in front of the print head around posts 125, 126, 127, and 128. Two motors drive ribbon ~1 back an~ forth between spools 42 and 43. *he printer control unit 3 detects ribbon jams and end of ribbon condition. A ribbon jam turns on an error indicator and stops printing.
The printer includes an operator panel 26 that consists of several operator control keys, two indicator lights, a power on/off switch, an operator panel display, and a density display.
Referring now to FIC. 4, print block 50 includes four groups of nine print wires 52 and associated actuator (not shown). Print block 50, print wires 52, and the print actuators are described in detail in Canadian Patent Application No. 358,503, filed Augus-t 19, 1980, by W.W. Boynton et al entitled "PrinteriSubsystem Wi-th Microprocessor Control". Each group of nine print wires 52 is referred to as a print head and is respectively designated heads 1 through 4.
Each of the print wires 52 is, in turn, respectively numbered 1 through 9, vertically from top to bottom with wires 1 through 5 being on a first slanted path, such - that adjacent wires 52 are separated horizontally by l~C~ 1.t~
3 ~
0.40 inches allcl vertieally by 0.01~7 inches. Ally number of print heacis may be used, sucll as Eor-example two, four or seven.
As shown in EIG. 5, a verticcll or slallt matrix printer having two heads 54 in gang relatlollslli~) eaeh of whieh are normally assigned to a predetermined zone along a print line extent. In low density printing, the garlc3 heads 5~ would be positionecl to the left of the first: eharacter to be printed and inerementally movecl left to rigllt until the heads were positioned just to the rigllt of the last char-ac-ter to be ~rinted upon that line. I~t thls point, -the medium would be advanced so -that the gang heads eould be aetuated for printing purposes in a riyll-t to left direetion for the next print line. 'l`he use of multiple heads and zones increases print speed beeause the heads are driven in parallel over a shorter distanee.
Referring now to FIG. ~, thcre is shown the detail of -the normal low vertieal clensity priilting within the zonal boundaries. Typieally, a head will print dot matrix eharacters haviny .020 illC}l spacinCI t}lerebetWeell horizontally and .0167 inehes vertieall~. Tlle other head is vertically offset. The amount of vertlcal oEfset is .00833 inehes. This is a half a dot eharaeter spaeing.
FIG. 7 shows the detail of high c~uality printing in whieh the horizontal dot spaeing is .010 inehes and the vertieal dot spaeing in any vertieal row is .00833 inches.
Where it is desired to write a line of c3uality prlnting left to right, the ganged heacls are positionecl sueh that the right most head is to the left of the irst eharaeter. Assuming the riclht most heacl is vertically displaeed lower tllan the left head, a character as shown in the right most E in FIG. 7 would be first laid O~lt all along the print extent whilc? the second or left most head would overs-trike each eharaeter position with the same character in the same order but offset vertieally BC9~ ()16 ~ 3~
upwards to a~hleve tlle vert.ical anclllori~onLa:L print density shc)wll in ~'IG. 7. Tlle gancJecl print head movement would contillue ulltil. t:he .l.ef t IllOSt head was positioned to the rigtlt of the last character at thc right end of the line to be prlllted. The print rate for quality prilltillg is l~n of the draEt printing, wllere n i.s the number of ganged heads.
Si(.~nLficclntly, the ganged relationship arnong the heads is not malldatory, althoucJh it does obviate problems of maintaining synchronism of data and . ~.
position. It will be further understood by those skilled in the art that the alternate print heads are _ _ ~
horizontally aligned with respect to one another so that the dots of one of the two alternate print heads imprints dots between previously printed dots of the other of the alternate print heads. The heads are COIl trolled in the quality print mode to print over two portions of the line whereby quality printed dot matrix characters result. By controllably printing in the draft mode, -the print quality is of sparse density.
It will be further understood by those skilled in this art that various other changes in the form and details may be made therein without departing from -the spirit and scope of the invention.
3~
SEI.ECTlVE DENSII'Y PRINTING USING DOT
MATRIX PRINT ~-IEADS IN FIXED SPATIAL RELATION
Technical Field This invention relates to dot ma-trix printers and, more particularly, to selectively varying the dot density and print quality.
Background In order to achieve quality or "pretty" printed characters, one relies upon a relatively smooth character contour in addition to a hiyh contrast (black/white) ratio between character and the recording medium. Where a character is formed on a medium ~rom a matrix of dots produced by a wire matrix print head through a ribbon, the contrast ratio is a functi.on of the dot density. In this regard, character contour or smoothness is a function of the overlap relationship among the dots especially in the vertical direction.
Martin, et al., USP 4,010,835 issued 8 March 1977, describes a wire matrix print head arranged to provide two different printing arrays. In a first embodiment, the print wires are contained in two guides, one of which can be translationally displaced in a vertical direction from the other guide which is held in a fixed position. In a second embodiment, the wires are arranged in a single wire guide rotatable about an axis which is perpendicular to the document and parallel to the print wires. Further, in Martin the print head is translated horizontally from left to right to print across a line on BC9-80-0l6 a document. Printing i.s e:Efected by the impact of se1ectkd plura]ities of print wires, each of which is provided with a separate actuator arranged so that when the actuator is eneryiæed, -the associated print wi.re is driven forwared to impact the paper. An inlced rihbon is interposed between the document (recordinc~ medium) and the print wires. The impact oF the print wi.re on the ribbon causes a do-t to be printed at a selected point on the document. By energizing combinations of actuators, combinations of print wires can be imprinted corresponding to a selected character.
In the prior art, it has been customary to fabricate a single vertical wire column print head with wires bent along a portion of their extent. This bend creates a long wire path subjec-t to breakage and friction. Replacement of wires in such a head is not feasi~le. In contrast, a relatively never-fail print head may be fashioned from wires being laid in a diagonal rather than column array.
Reference should be made to Leontiades, USP
4,284,001, issued 18 August 1981 showing a wire matrix printer having a plurality of print heads in which the wires are positioned in slanted relationship. In this arrangement, it is possible for a slant head to be involved with two or more characters. The overlapping of the slant heads and dotted character matrices creates a complex mapping relationship between both the data points and the print wire matrix.
Choberka, et al., USP 4,284,363, issued 18 August 1981, describes a dot matrix tilting print head assembly in which the print head is rotatably mounted and framed. The dot matrix print head has its wires actuated to cause dots to be printed on the recordiny medium while the BC9-80-0~.6 print head is :Iaterally moved across the medium, the centers o~ the dots being separa-tecl by a given dlstance. In order to :i~prove print quality, there i.s involved the insertion of dots between previously printed dots by controlling the rotation.
The Invention The -technical problem solved by this invention is to vary the density within prin-ted dot matrix characters by selectively overstriking the same mediurn position with the same character or a portion thereof positionally offset in at least one direction without requiring that the medium be moved or complex rotational head motion be involved. The solution involves partitioning each print line extent into several zones and assigning print heads to the counterpart zones; positioning the heads in fixed verti.cal offset relation to each other, and selectively causing each head to imprint the mediurn wi-thin its zone for low density and to overstrike a designated position within ano-ther zone with a predetermined character or portion thereof for high density.
Significantly, the printer includes a plurality of print heads, each posltioned to print a portion of the line and each including a plurality of wires which print dots separated by a given distance.
Corresponding wires of one of the alterna-te print heads is horizontally aligned to print dots between printed dots of the other of the alternate print heads. A
vertical displacement or offset of one-half character dot between overstrik.ing pairs of heads yields aesthetically pleasing dot matrix characters. For low density, the half character dot displacement between the characters in the zones is not readily discernible to the eye. Advantageously, the sc9-80-016 ~ 3~
~1 only mechallical mot:i.on ls the horizonta]. di..spl.acement of the preferably ganged print heads.
Brie:E Summary of the Drawings FIG. 1 is a simplifled system diagram for a dot matrix printer system of the type within which the inven-tion is contained;
FIG. 2 illustrates the printer conso].e inclucling the recording medium propagation path in relation to the print head mechanism;
FIG. 3 is a frontal view of the printer unit in the console shown in FIG. 2;
FIG. 4 illustrates four heads of nine-wire per head printing bloc~;
FIG. 5 depicts the recording medium partiti~ned into prin-t zones;
FIGS. 6 and 7 show the dot distribution in low and high density printing.
Description of the Preferred Embodiment and Industrial Applicability The wire matrix printer is substantially of the type described in Leontiades, USP 4,284,001 issued August 18, 1981.
Referring now to FIG. 1, there is shown a represen~ative system configuration including a host system 1, and a printer system 2. The printer system includes a BC9-~30--Q I 6 3''~
con-trol uni-t 3 and an attachment logic 4. Command and da-ta signals are provldecl by the host system to printer control unit 3 by way of bus 5. Command and control signals are obtalned from printer control unit 3 over the printer adapter 4 by way of bus 6. Status signals are supplled by the printer control unit 3 to host system 1 over bus 5. Typically, the host system applies sequences of commands and data to the printer and monitors status in return. Control unit 3 receives the eommands, decodes them, checks for errors, and generates status information. Control unit 3 further regulates printing and spacing and includes local diagnostics. The adapter 4 executes decoded control unit commands, monitors all printer operations, actuates print wires, drives motors, senses printer emitters, and controls operator panel lights and switching circuitry. Also, the adapter controls the traetors, the ribbon drive, the print head carrier, the operator panel, and the printer sensors. It should be appreciated that the printer control unit 3 and adapter 4 incorporate one or more mieroprocessors for analyzing eommands and data and to regulate operations.
FIGS. 2 and 3 illustrate eomponents of the printer housed in console 10. Aecess panels or covers 11, 12, 13 keep a relatively clean industry environment. Top cover 11 has a window 14 enabling an operator to observe paper path movement during operation of the printer whenever the cover is closed. The recording medium is paper 15. It is obtained from a stored stack 16 and is fed into an upwardly or downwardly transversing paper path as seen in FIGSo 2 and 3 by way of a mechanical assembly 20 which includes one or more sets of tractors 90 and 91. A guide 28 moves the paper after printing to a takeup stack ~not shown) positioned below the printing mechanism and to the rear of the console. The printer incorporates a print assembly 30 which is positioned in a horizontal ~3~3~
relationslli~ with respect to the mecliuln ~5 at;a prillt station 32. The printer ribbon drive assembly 40 is located in closer proximity to the front of the printer.
The printer control unit 3 and its associated micro-processors are situated behind the side cover 13.
A ribbon ~1 is provided on one of the spools ~2 or43. Each ribbon box preferably contains a disposable ribbon shoe ~6 mounted on spring attachment members 130 and 13l between print assembly 30 and the medium 15 in order to maintain rib~on 41 in proper alignment and to minimize ink smudging on the medium. The ribbon moves on a path in front of the print head around posts 125, 126, 127, and 128. Two motors drive ribbon ~1 back an~ forth between spools 42 and 43. *he printer control unit 3 detects ribbon jams and end of ribbon condition. A ribbon jam turns on an error indicator and stops printing.
The printer includes an operator panel 26 that consists of several operator control keys, two indicator lights, a power on/off switch, an operator panel display, and a density display.
Referring now to FIC. 4, print block 50 includes four groups of nine print wires 52 and associated actuator (not shown). Print block 50, print wires 52, and the print actuators are described in detail in Canadian Patent Application No. 358,503, filed Augus-t 19, 1980, by W.W. Boynton et al entitled "PrinteriSubsystem Wi-th Microprocessor Control". Each group of nine print wires 52 is referred to as a print head and is respectively designated heads 1 through 4.
Each of the print wires 52 is, in turn, respectively numbered 1 through 9, vertically from top to bottom with wires 1 through 5 being on a first slanted path, such - that adjacent wires 52 are separated horizontally by l~C~ 1.t~
3 ~
0.40 inches allcl vertieally by 0.01~7 inches. Ally number of print heacis may be used, sucll as Eor-example two, four or seven.
As shown in EIG. 5, a verticcll or slallt matrix printer having two heads 54 in gang relatlollslli~) eaeh of whieh are normally assigned to a predetermined zone along a print line extent. In low density printing, the garlc3 heads 5~ would be positionecl to the left of the first: eharacter to be printed and inerementally movecl left to rigllt until the heads were positioned just to the rigllt of the last char-ac-ter to be ~rinted upon that line. I~t thls point, -the medium would be advanced so -that the gang heads eould be aetuated for printing purposes in a riyll-t to left direetion for the next print line. 'l`he use of multiple heads and zones increases print speed beeause the heads are driven in parallel over a shorter distanee.
Referring now to FIG. ~, thcre is shown the detail of -the normal low vertieal clensity priilting within the zonal boundaries. Typieally, a head will print dot matrix eharacters haviny .020 illC}l spacinCI t}lerebetWeell horizontally and .0167 inehes vertieall~. Tlle other head is vertically offset. The amount of vertlcal oEfset is .00833 inehes. This is a half a dot eharaeter spaeing.
FIG. 7 shows the detail of high c~uality printing in whieh the horizontal dot spaeing is .010 inehes and the vertieal dot spaeing in any vertieal row is .00833 inches.
Where it is desired to write a line of c3uality prlnting left to right, the ganged heacls are positionecl sueh that the right most head is to the left of the irst eharaeter. Assuming the riclht most heacl is vertically displaeed lower tllan the left head, a character as shown in the right most E in FIG. 7 would be first laid O~lt all along the print extent whilc? the second or left most head would overs-trike each eharaeter position with the same character in the same order but offset vertieally BC9~ ()16 ~ 3~
upwards to a~hleve tlle vert.ical anclllori~onLa:L print density shc)wll in ~'IG. 7. Tlle gancJecl print head movement would contillue ulltil. t:he .l.ef t IllOSt head was positioned to the rigtlt of the last character at thc right end of the line to be prlllted. The print rate for quality prilltillg is l~n of the draEt printing, wllere n i.s the number of ganged heads.
Si(.~nLficclntly, the ganged relationship arnong the heads is not malldatory, althoucJh it does obviate problems of maintaining synchronism of data and . ~.
position. It will be further understood by those skilled in the art that the alternate print heads are _ _ ~
horizontally aligned with respect to one another so that the dots of one of the two alternate print heads imprints dots between previously printed dots of the other of the alternate print heads. The heads are COIl trolled in the quality print mode to print over two portions of the line whereby quality printed dot matrix characters result. By controllably printing in the draft mode, -the print quality is of sparse density.
It will be further understood by those skilled in this art that various other changes in the form and details may be made therein without departing from -the spirit and scope of the invention.
Claims (3)
1. A method for varying the density within printed dot matrix characters by selectively overstriking the same print medium position with the same character or portion thereof positionally offset in at least one direction, characterized by the steps of:
partitioning each recording medium print line extent into n zones and assigning n print heads to counterpart zones;
positioning the n heads in vertical offset relation from each other;
ganging alternate heads;
selectively causing each head to imprint the medium within its zone for low density and to overstrike a designated position within another zone with a predetermined character for high density; and writing a line of characters from left to right by initially positioning the ganged heads such that the rightmost head is to the left of the first character, and then causing the rightmost head to strike a character on the medium while causing the second or leftmost head to overstrike each character position with the same character in the same order but offset vertically, the ganged print head movement continuing until the leftmost head is positioned to the right of the last character at the right end of the line to be printed.
partitioning each recording medium print line extent into n zones and assigning n print heads to counterpart zones;
positioning the n heads in vertical offset relation from each other;
ganging alternate heads;
selectively causing each head to imprint the medium within its zone for low density and to overstrike a designated position within another zone with a predetermined character for high density; and writing a line of characters from left to right by initially positioning the ganged heads such that the rightmost head is to the left of the first character, and then causing the rightmost head to strike a character on the medium while causing the second or leftmost head to overstrike each character position with the same character in the same order but offset vertically, the ganged print head movement continuing until the leftmost head is positioned to the right of the last character at the right end of the line to be printed.
2. A method according to claim 1 whereby the positioning step further includes the step of maintaining a vertical offset among selected pairs of heads to be within one-half dot character overlap relation.
3. In a wire matrix printer for printing a line of characters on a record medium, said printer having a plurality of print heads, each head positioned to a print portion of the line and each head including a plurality of wires which prints dots separated by a given distance, characterized by:
corresponding wires of ones of the alternate print heads being horizontally aligned so as to print dots between printed dots of the other of the alternate print heads;
means for ganging alternate print heads;
said printer including control means for selecting whether each print head is to print in either one or two portions of said line of characters; and means including the ganging and control means for causing the overstriking of a character dot pattern by a second and alternate print head.
corresponding wires of ones of the alternate print heads being horizontally aligned so as to print dots between printed dots of the other of the alternate print heads;
means for ganging alternate print heads;
said printer including control means for selecting whether each print head is to print in either one or two portions of said line of characters; and means including the ganging and control means for causing the overstriking of a character dot pattern by a second and alternate print head.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US33289881A | 1981-12-21 | 1981-12-21 | |
| US332,898 | 1981-12-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1191390A true CA1191390A (en) | 1985-08-06 |
Family
ID=23300340
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000417174A Expired CA1191390A (en) | 1981-12-21 | 1982-12-07 | Selective density printing using dot matrix print heads in fixed spatial relation |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0082336B1 (en) |
| JP (1) | JPS58110266A (en) |
| CA (1) | CA1191390A (en) |
| DE (1) | DE3278761D1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5611630A (en) * | 1995-12-27 | 1997-03-18 | Pitney Bowes Inc. | Method and apparatus for securely printing a postal indicia image having a different dot density in two dimensions thereof |
| US5769550A (en) * | 1995-12-27 | 1998-06-23 | Pitney Bowes Inc. | Method and apparatus for securely printing an indicia image in multiple passes including an enhancement pass |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0145025B1 (en) * | 1983-12-14 | 1990-07-25 | Oki Electric Industry Company, Limited | Multihead serial printer |
| DE3730844A1 (en) * | 1987-09-14 | 1989-03-23 | Siemens Ag | MATRIX WRITER |
| EP0331481B1 (en) * | 1988-03-02 | 1994-06-22 | Canon Kabushiki Kaisha | Recording apparatus in which a plurality of carriages can be connected and separated |
| JP2785031B2 (en) * | 1988-03-02 | 1998-08-13 | キヤノン株式会社 | Serial printer |
| CN102750264A (en) * | 2012-06-12 | 2012-10-24 | 华东师范大学 | True type font-bold data processing method |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL7613358A (en) * | 1976-12-01 | 1978-06-05 | Philips Nv | CONTROL DEVICE FOR A MATRIX PUSHER. |
| DE2633978C2 (en) * | 1976-07-28 | 1978-04-20 | Oki Electric Industry Co., Ltd., Tokio | Method and circuit arrangement for intermediate point printing in dot printers |
| IL56669A0 (en) * | 1978-02-15 | 1979-05-31 | Nori Sinoto | Matrix printer |
| JPS5527266A (en) * | 1978-08-17 | 1980-02-27 | Nec Corp | High speed dott matrix printer |
| JPS55111273A (en) * | 1979-02-15 | 1980-08-27 | Rogon Corp | Printer and its method |
| US4284001A (en) * | 1979-10-19 | 1981-08-18 | International Business Machines Corp. | Head image generator for a matrix printer |
| JPS5663677A (en) * | 1979-10-30 | 1981-05-30 | Oki Electric Ind Co Ltd | Printing control system of dot printer |
-
1982
- 1982-11-23 EP EP19820110825 patent/EP0082336B1/en not_active Expired
- 1982-11-23 DE DE8282110825T patent/DE3278761D1/en not_active Expired
- 1982-12-07 CA CA000417174A patent/CA1191390A/en not_active Expired
- 1982-12-09 JP JP21479282A patent/JPS58110266A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5611630A (en) * | 1995-12-27 | 1997-03-18 | Pitney Bowes Inc. | Method and apparatus for securely printing a postal indicia image having a different dot density in two dimensions thereof |
| US5769550A (en) * | 1995-12-27 | 1998-06-23 | Pitney Bowes Inc. | Method and apparatus for securely printing an indicia image in multiple passes including an enhancement pass |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0082336B1 (en) | 1988-07-13 |
| DE3278761D1 (en) | 1988-08-18 |
| EP0082336A2 (en) | 1983-06-29 |
| JPS6311153B2 (en) | 1988-03-11 |
| EP0082336A3 (en) | 1985-08-21 |
| JPS58110266A (en) | 1983-06-30 |
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| MKEC | Expiry (correction) | ||
| MKEX | Expiry |