US3802546A - Web clamping apparatus - Google Patents

Web clamping apparatus Download PDF

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Publication number
US3802546A
US3802546A US00154573A US15457371A US3802546A US 3802546 A US3802546 A US 3802546A US 00154573 A US00154573 A US 00154573A US 15457371 A US15457371 A US 15457371A US 3802546 A US3802546 A US 3802546A
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US
United States
Prior art keywords
coil
coil structure
pressure plate
conductor
plane
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 - Lifetime
Application number
US00154573A
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English (en)
Inventor
C Helms
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Printing Systems America Inc
Original Assignee
Dataproducts Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Dataproducts Corp filed Critical Dataproducts Corp
Priority to US00154573A priority Critical patent/US3802546A/en
Priority to CA143,475A priority patent/CA959705A/en
Priority to GB2660072A priority patent/GB1396156A/en
Priority to NLAANVRAGE7207707,A priority patent/NL170469C/xx
Priority to FR7220403A priority patent/FR2142366A5/fr
Priority to DE2229474A priority patent/DE2229474C3/de
Priority to IT25861/72A priority patent/IT956682B/it
Application granted granted Critical
Publication of US3802546A publication Critical patent/US3802546A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K33/00—Motors with reciprocating, oscillating or vibrating magnet, armature or coil system
    • H02K33/18—Motors with reciprocating, oscillating or vibrating magnet, armature or coil system with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets
    • 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
    • B41J15/00—Devices or arrangements of selective printing mechanisms, e.g. ink-jet printers or thermal printers, specially adapted for supporting or handling copy material in continuous form, e.g. webs
    • B41J15/16—Means for tensioning or winding the web

Definitions

  • ABSTRACT An electrically actuable clamping device useful in a web feed apparatus such as 'a high speed impact printer for preventing movement of the paper during printing.
  • the clamping device comprises a large flat coil structure supported by a plurality of flexure members such as leaf springs, and oriented in a plane extending substantially perpendicular to the plane of the paper.
  • a permanent magnet field isdeveloped perpendicular to the plane of the coil so that when current is driven through the coil, a force is produced which acts to move the coil structure forward to clamp the paper against a pressure plate.
  • the coil current is developed by a closed loop circuit in which a coil structure velocity signal is fed back to enable the coil structure to be moved rapidly, quietly, and without impact or marking between clamp" and release positions.
  • the velocity signal is developed by a transducer including a small coil carried by the large coil structure.
  • Impact printers are well known in the data processing field for providing hard copy computer output.
  • such printers comprise a type surface, such as a character drum or chain, which continually moves past a printing station comprised of a bank of aligned individually actuatable hammers.
  • a paper web and an ink web are disposed between the hammer bank and type surface.
  • the paper is normally stepped one line at a time with a full line being printed between successive paper movements. Printing is accomplished by actuating each hammer at the appropriate time to propel it against the type surface when the character to be printed moves into alignment with the hammer striking face.
  • Print quality in terms of registration between characters in a single line, is also affected by how rigidly the paper drive system holds the paper under impact. That is, even if a settling time duration is selected which assures that the paper movement has been completely damped prior to printing, as a practical matter, there is always some degree of compliance and backlash within the elements (e.g. belts, etc.) of the paper drive system. As a consequence of this complicance and backlash, the initial hammer impact against the character drum, after paper settling, may move the paper as the paper is dragged by the continually rotating drum. More particularly, consider the drum surface moving downwardly past the hammer faces.
  • an object of the present invention is to provide an improved means for controllably clamping a web.
  • a web clamping means in accordance with the present invention comprised of a large coil structure supported for linear movement within a permanent magnet field. More particularly, the coil structure is supported by flexure members such as leaf springs.
  • the coil structure is preferably oriented in a plane extending perpendicular to the plane of the web so that a force developed in response to a current driven through the coil will project the coil structure forwardly to thus clamp the web against an opposed pressure plate.
  • the front edge surface of the coil structure is shaped to conform to the opposed pressure plate surface to hold the web fixed and flat.
  • the coil structure is linearly displaced in a controlled manner by employing a closed loop circuit to develop the coil drive current. Moree particularly, a command signal is generated which is summed with a feed back signal representative of coil structure velocity to develop an error signal for producing the coil current.
  • the command signal is shaped so as to controllably reduce the coil structure velocity to substantially zero upon reaching the forward clamp position or the rearward quiescent release" position.
  • the transducer provided to produce a velocity feedback signal is comprised of a small coil carried by the large coil structure and movable in a permanent magnet field.
  • the transducer coil is preferably oriented transverse to the coil structure to minimize inductive coupling therebetween.
  • means are provided for selectively applying oppositely directed bias currents to said coil to hold said coil structure in either said clamp or release positions.
  • FIG. 1 is a side view illustrating a portion of a high speed impact printer incorporating a clamping device in accordance with the present invention
  • FIG. 2 is a sectional view taken substantially along the plane 2-2 of FIG. 1;
  • FIG. 3 is a sectional view taken substantially along the plane 3-3 of FIG. 1;
  • FIG. 4 is a block diagram of a closed loop control circuit for developing the coil drive current.
  • FIG. 5 is a wave form diagram illustrating various signals occurring within the circuit of FIG. 4.
  • FIG. 1 of the drawing schematically illustrates a portion of a high speed impact printer frequently used as a data processing output device.
  • the printer 10 usually consists of a movable type surface in the form of a drum 12 mounted for rotation about an axis 14.
  • the drum 12 normally has raised alphanumeric characters (not shown) formed in circumferential tracks extending around the drum surface Typically, a drum 12 may have 132 tracks which enables a line of 132 characters to be printed.
  • a different hammer 16 in a hammer bank 18 Positioned opposite to each of the drum tracks is a different hammer 16 in a hammer bank 18.
  • a paper web 20 threads the space between the hammer striking faces 22 and the surface of the drum l2.
  • the printing ribbon 24 is disposed between the paper web 20 and the drum surface.
  • the paper web 20 is normally provided with edge perforations (not shown) adapted to be engaged with fingers 26 formed on a tractor chain 28.
  • the tractor chain 28 is driven by a gear 29 which in turn may be belt driven by a motor responsive to signals provided by paper control circuitry (not shown).
  • Suitable paper drive systems are disclosed in greater detail in U. S. Pat. Nos. 3,423,658 and 3,452,853.
  • the paper web 20 is stepped one line at a time in the direction of the arrow 32 at rates up to about 2,000 lines per minute.
  • a full line can be printed, normally in one full rotation of the drum 12. That is, in one full rotation of the drum 12, a full set of characters will move past the striking face 22 of each of the hammers 16.
  • a hammer 16 against the drum 12 By impacting a hammer 16 against the drum 12 when the desired character is in alignment therewith, that character will be printed on the surface of the paper web 20 adjacent to the ink ribbon 24.
  • a particuarly suitable hammer structure is disclosed in U. S. Pat. No. 3,279,362.
  • a clamping device 40 in accordance with the present invention is preferably mounted downstream (and/or upstream) from a printing station in the printer 10, of FIG. 1.
  • the clamping device 40 is comprised of a flat coil structure 42 which includes a rigid elongated frame 44.
  • the frame 44 has long front and rear edge surfaces 46 and 48 and relatively short end surfaces 50 and 52.
  • a multiturn conductor coil 54 is housed within the coil structure 42 between top and bottom plates 56 and 58.
  • the coil structure 42 preferably includes a central cutout area 60 to reduce the coil structure mass.
  • a pressure bar 62 is securely fixed to the coil structure front edge surface 46.
  • the coil structure 42 is supported by front and rear flexure members 64 and 66 depending from magnetic structural members 68.
  • the flexure members 64 and 66 preferably comprise leaf springs and, as shown, support the coil structure 42 in an essentially horizontal plane extending substantially perpendicular to the plane of the paper web 20.
  • a pressure plate 70 is mounted in alignment with the pressure bar 62 but on the opposite side of the path of paper web 20. By moving the coil structure 42 forwardly toward the pressure plate 70, the paper web 20 will be clamped and held therebetween.
  • the coil structure 42 is mounted in a magnetic field produced by permanent magnets.
  • the permanent magnets can comprise unitary U-shaped structures or can be formed, as shown in FIG. 1, by bar magnets 74 and 76 mounted on a magnetic support member 68. Similarly,
  • magnets 78 and 80 are mounted on a second magnetic support member 82.
  • the magnet configuration produces a magnetic flux path generally represented by the dash line 84 which extends across the gaps between magnets 74 and 78 and between magnets 76 and 80.
  • dash line 84 which extends across the gaps between magnets 74 and 78 and between magnets 76 and 80.
  • FIGS. 4 and 5 of the drawing illustrate a suitable control circuit 90 for developing a drive current for application to the coil 54.
  • the circuit 90 comprises a closed loop circuit which enables the coil structure 42 to be controllably linearly displaced from the' quiescent release position shown in FIG. 1 to a clamp position in which the pressure bar 62 clamps the paper web against the pressure plate 70.
  • Line (a) of FIG. 5 represents a command signal provided to the paper feed motor in order to step the paper web 20 one line.
  • the paper web 20 is moved in a manner represented by the velocity waveform of line (b). Note that the paper velocity is linearly increased from rest, represented by base line 100 to some maximum velocity represented by level 102. Once the paper web 20 approaches its destination position, the paper velocity is linearly reduced, shown by sloped line 104, so that the paper velocity reaches zero, represented by base line 106, concurrent with the arrival of the paper web 20 at its destination position.
  • the leading edge 110 of the paper feed input signal (FIG. 5, line (a) initiates paper movement and in addition, in accordance with the present invention, is utilized by the circuit 90 of FIGQ4 to move the pressure bar 62 on the clamping device 40 from the clamp to the release position. More particularly, in response to the leading edge 110 of the paper feed input signal, a release command pulse 114 (FIG. 5, line (c) is developed on the control logic output terminal 116. Tenninal l 16 is connected to the input of a command generator circuit 118. As shown in line (e) of FIG. 5, in response to the leading edge 120 of the release command pulse 114, the command generator 118 produces an output signal of increasing amplitude as represented at 122.
  • the command generator output decreases toward zero represented by line 126.
  • the positive and negative going excursions 122 and 126 of the command generator output act respectively to accelerate the coil structure 42 rearwardly and to then decelerate the coil structure 42 so that its velocity is reduced to substantially zero coincident with its arrival at the quiescent release position illustrated in FIG. 1.
  • a hold command pulse 130 (FIG. 5, line (d) is developed by the control logic 108 on output terminal 131.
  • the leading and trailing edges 132 and 136 of the pulse 130 produce negative and positive going excursions 134, 138 respectively in the command generator output signal (FIG. 5, line (e)
  • the effect of the negative and positive going excursions 134 and 138 in the command generator output signal is to initially accelerate the coil structure 42 in a forward direction toward the pressure plate 70 and to then reduce the forward velocity to zero substantially coincident with the engagement of the pressure bar 62 against the pressure plate 70.
  • the output of the command generator 118 is applied through a resistor 140 to a summing junction 142 at the input of an error amplifier 144.
  • the output of the error amplifier 144 is supplied to a power amplifier 146 which develops a current for application to the conductor coil 54 of the coil structure 42.
  • a velocity transducer 150 is provided to develop a velocity signal which is then fed back to the summing junction 142 of the error amplifier 144.
  • the signal produced by the velocity transducer 150 is coupled through a switch 152 and a resistor 154 to the summing junction 142.
  • the switch 152 is controlled by an output terminal 156 of the control logic means 108 so that it is enabled (FIG. 5, line (i) during the entire paper feed sequence illustrated in FIG. 5.
  • the velocity of the coil structure 42 will indeed correspond to that represented by the generator output signal of FIG. 5, line (e). It should be appreciated from the waveform that the velocity of the coil structure 42, both for forward movement to the clamp position and for rearward movement to the release position, will be reduced to zero substantially coincident with the arrival of the coil structure 42 at the respective positions thereby assuring quiet operation of the clamping device 40. More significantly, however, the clamping device 40 will operate quite rapidly since the coil structure 42 will settle immediately upon arrival at its destination position.
  • a bias current (FIG. 5, line (h) is supplied to the coil 54 by the control logic means 108. More particularly, the hold bias current 170 is supplied at all times except during the paper feed sequence which is initiated coincident with the leading edge 110 of the paper feed input signal and terminated coincident with the forward velocity of the coil structure 42 being reduced to zero. Thus, at all times other than when the paper web 20 is being moved, the coil structure 42 will be clamped against the pressure plate 70 as a consequence of the hold bias current 170 supplied to the summing junction 142 via the resistor 172.
  • a release bias current 176 (FIG.
  • line (g) opposite in polarity to the hold bias current 170 is applied to the coil 54 during the paper feed sequence of FIG. via resistor 178 coupled to the summing junction 142.
  • Line (f) of FIG. 5 illustrates the current through the coil 54 produced as a consequence of the sum of the various signal components supplied to the summing junction 142.
  • FIGS. 1-3 illustrate a particularly useful velocity transducer embodiment for developing the coil structure velocity signal fed back through switch 152 to the summing junction 142.
  • the velocity transducer 150 comprises a coil 180 physically secured to the coil structure 42. As the coil structure 42 moves, the coil 180 correspondingly moves within a gap defined by an upper pair of permanent magents 182 and 184 and a lower pair of permanent magnets 186 and 188.
  • the permanent magnets 182, 184, 186, and 188 produce flux along a path represented by the dash line 190 shown in FIG. 3.
  • coil 180 cuts the flux lines produced by the permanent magnets 182, 184, 186, 188, it will develop an output signal related to the rate of change of flux. Consequently, the coil 180 will produce a signal at its output terminals representative of the velocity of coil 180 which, of course, is also the velocity of the coil structure 42. It is pointed out that the coil 180 is preferably mounted transverse to the coil 54, as illustrated in FIGS. 1-3, in order to minimize any inductive coupling therebetween.
  • a web clamping device 40 has been disclosed herein which can operate rapidly and quietly to selectively clamp the web in a web feed type apparatus, such as a high speed printer 10.
  • a web feed type apparatus such as a high speed printer 10.
  • a particular embodiment of the invention has been shown herein, it is recognized that variations and modifications within the scope of the invention may readily occur to those skilled in the art.
  • a single clamping device 40 has been illustrated in the drawing downstream from the print station, it may be preferable in some embodiments to employ clamping devices 40 both upstream and downstream from the print station.
  • a flat fixed pressure plate 70 has been shown, the invention is also useful in embodiments where, for example, the pressure plate surface is other than flat and where the pressure plate 70 may be movable toward the coil structure 42.
  • clamping device 40 has been disclosed for use in conjunction with a velocity servo loop, it should be recognized that alternatlvely, or additionally, coil structure position information can be fed back to thereby enable the. position of the coil structure 42 to be precisely controlled for establishing a desired force on the web 20.
  • Apparatus suitable for clamping web material to prevent movement of said material comprising:
  • a planar coil structure having a clamping surface extending substantially the full length thereof, said coil structure including a conductor coil defining an axis extending perpendicular to the plane of said coil structure;
  • said means producing a magnetic field includes permanent magnets supported on at least one side of the plane of said coil structure.
  • transducer means responsive to said coil structure velocity for developing a feedback signal
  • said means for driving a current through said conductor coil includes means responsive to said feedback signal.
  • said means supporting said coil structure includes a plurality of flexure members secured between said coil structure and a fixedly mounted base member.
  • the apparatus of claim 1 including:
  • Apparatus suitable for clamping web material to prevent movement of said material comprising:
  • a planar coil structure having a clamping surface extending substantially the full length thereof, said coil structure including a conductor coil defining an axis extending perpendicular to the plane of said coil structure;
  • said means for driving a current through said conductor coil including (1) means for generating a command signal (2) transducer means responsive to said coil structure for developing a feedback signal and (3) means responsive to said command and feedback signals for producing a drive signal for application to said conductor coil;
  • said transducer means for developing said feedback signal including a relatively small planar flat coil having terminals and mounted on said coil structure for movement therewith;
  • clamping means for clamping said paper web to prevent movement thereof, said clamping means comprising:
  • a fiat rigid coil structure having a clamping surface extending substantially the full length thereof and including a conductor coil defining an axis extending perpendicular to the plane of said coil structure;
  • the printer of claim 8 including a fixedly mounted base member; and wherein said means supporting said coil structure includes a plurality of flexure members secured between said base member and said coil structure.
  • the printer of claim 8 including a transducer means responsive to the velocity of said coil structure for developing a feedback signal
  • the printer of claim 8 including:
  • clamping means for clamping said paper web to prevent movement thereof, said clamping means comprising:
  • said means for driving a current through said conductor coil including 1) means for generating a command signal, (2) transducer means responsive to said coil structure for developing a feedback signal and (3) means responsive to said command and feedback signals for producing a drive signal for application to said conductor coil; said transducer means for developing said feedback signal including planar coil means having terminals and mounted on said coil structure for movement therewith for developing a velocity feedback signal; means for producing a magnetic field across said coil means extending substantially perpendicular to the plane of said coil means; and means for obtaining said velocity feedback signal from across the terminals of said coil means.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Registering, Tensioning, Guiding Webs, And Rollers Therefor (AREA)
  • Replacement Of Web Rolls (AREA)
US00154573A 1971-06-18 1971-06-18 Web clamping apparatus Expired - Lifetime US3802546A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US00154573A US3802546A (en) 1971-06-18 1971-06-18 Web clamping apparatus
CA143,475A CA959705A (en) 1971-06-18 1972-05-30 Web clamping apparatus
GB2660072A GB1396156A (en) 1971-06-18 1972-06-07 Web clamping apparatus
NLAANVRAGE7207707,A NL170469C (nl) 1971-06-18 1972-06-07 Papiertransportinrichting van een drukinrichting, waarbij het papier stap voor stap verplaatst wordt.
FR7220403A FR2142366A5 (enExample) 1971-06-18 1972-06-07
DE2229474A DE2229474C3 (de) 1971-06-18 1972-06-16 Vorrichtung zum Bremsen und Festklemmen von Bahnmaterial, insbesondere für einen Drucker
IT25861/72A IT956682B (it) 1971-06-18 1972-06-17 Apparecchiatura per serraggio del nastro in stampatrice a battuta

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00154573A US3802546A (en) 1971-06-18 1971-06-18 Web clamping apparatus

Publications (1)

Publication Number Publication Date
US3802546A true US3802546A (en) 1974-04-09

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Application Number Title Priority Date Filing Date
US00154573A Expired - Lifetime US3802546A (en) 1971-06-18 1971-06-18 Web clamping apparatus

Country Status (7)

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US (1) US3802546A (enExample)
CA (1) CA959705A (enExample)
DE (1) DE2229474C3 (enExample)
FR (1) FR2142366A5 (enExample)
GB (1) GB1396156A (enExample)
IT (1) IT956682B (enExample)
NL (1) NL170469C (enExample)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4098389A (en) * 1976-08-20 1978-07-04 Bunker Ramo Corporation Three position platen control mechanism
US4167346A (en) * 1976-08-19 1979-09-11 Nixdorf Computer Ag Apparatus for the timed transporting of forms
US4400106A (en) * 1974-11-29 1983-08-23 Patology Press, Ltd. Typesetting apparatus
EP0091685A1 (en) * 1982-04-12 1983-10-19 Polaroid Corporation Electromagnetic actuators
US4673306A (en) * 1984-07-11 1987-06-16 Dataproducts Corporation Magnetic paper clamp
US4896980A (en) * 1988-08-10 1990-01-30 Royden C. Sanders, Jr. Paper advancing system for high speed printers
US5040911A (en) * 1988-08-10 1991-08-20 Royden C. Sanders, Jr. Paper advancing system for high speed printers
US20040046863A1 (en) * 2002-06-26 2004-03-11 Creo Inc. Method and apparatus for clamping a printing media
US8292421B2 (en) * 2009-02-19 2012-10-23 Xerox Corporation Media hold-down device using tensioned thin guides
US11305563B1 (en) 2020-12-08 2022-04-19 Electronics For Imaging, Inc. Apparatus to flatten a substrate along a print path of a printer

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3135221A1 (de) * 1981-09-05 1983-03-17 Weitmann & Konrad GmbH & Co KG, 7022 Leinfelden-Echterdingen Bogenbremse
US4462528A (en) * 1982-06-18 1984-07-31 Polaroid Corporation Electrostatic web clamp
EP0961393A1 (de) 1998-05-28 1999-12-01 Sulzer Rüti Ag Linearmotor für eine Textilmaschine sowie Vorrichtung mit einem Linearmotor und Webmaschine mit dieser Vorrichtung

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3172353A (en) * 1963-06-17 1965-03-09 Data Products Corp Variable force hammer high speed printer
US3172352A (en) * 1963-05-13 1965-03-09 Data Products Corp Printing hammer assembly
US3279362A (en) * 1965-06-11 1966-10-18 Data Products Corp Printing hammer
US3282203A (en) * 1964-04-16 1966-11-01 Burroughs Corp Magnetically operated print hammers in high speed printers
US3285166A (en) * 1964-12-18 1966-11-15 Data Products Corp High speed print hammer and bar magnet means
US3323700A (en) * 1965-06-22 1967-06-06 Borg Warner Web driving system with driving, braking and motion sensing units adjacent each margin of the web
US3452853A (en) * 1966-10-10 1969-07-01 Data Products Corp Paper drive system
US3550745A (en) * 1967-02-08 1970-12-29 Gen Electric Information Syste Paper arresting device for high speed printers

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3172352A (en) * 1963-05-13 1965-03-09 Data Products Corp Printing hammer assembly
US3172353A (en) * 1963-06-17 1965-03-09 Data Products Corp Variable force hammer high speed printer
US3282203A (en) * 1964-04-16 1966-11-01 Burroughs Corp Magnetically operated print hammers in high speed printers
US3285166A (en) * 1964-12-18 1966-11-15 Data Products Corp High speed print hammer and bar magnet means
US3279362A (en) * 1965-06-11 1966-10-18 Data Products Corp Printing hammer
US3323700A (en) * 1965-06-22 1967-06-06 Borg Warner Web driving system with driving, braking and motion sensing units adjacent each margin of the web
US3452853A (en) * 1966-10-10 1969-07-01 Data Products Corp Paper drive system
US3550745A (en) * 1967-02-08 1970-12-29 Gen Electric Information Syste Paper arresting device for high speed printers

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4400106A (en) * 1974-11-29 1983-08-23 Patology Press, Ltd. Typesetting apparatus
US4167346A (en) * 1976-08-19 1979-09-11 Nixdorf Computer Ag Apparatus for the timed transporting of forms
US4098389A (en) * 1976-08-20 1978-07-04 Bunker Ramo Corporation Three position platen control mechanism
EP0091685A1 (en) * 1982-04-12 1983-10-19 Polaroid Corporation Electromagnetic actuators
US4673306A (en) * 1984-07-11 1987-06-16 Dataproducts Corporation Magnetic paper clamp
US4896980A (en) * 1988-08-10 1990-01-30 Royden C. Sanders, Jr. Paper advancing system for high speed printers
WO1990001416A1 (en) * 1988-08-10 1990-02-22 Sanders Royden C Jun Paper advancing system for high speed printers
US5040911A (en) * 1988-08-10 1991-08-20 Royden C. Sanders, Jr. Paper advancing system for high speed printers
US20040046863A1 (en) * 2002-06-26 2004-03-11 Creo Inc. Method and apparatus for clamping a printing media
US6837160B2 (en) * 2002-06-26 2005-01-04 Creo, Inc. Method and apparatus for clamping a printing media
US8292421B2 (en) * 2009-02-19 2012-10-23 Xerox Corporation Media hold-down device using tensioned thin guides
US11305563B1 (en) 2020-12-08 2022-04-19 Electronics For Imaging, Inc. Apparatus to flatten a substrate along a print path of a printer

Also Published As

Publication number Publication date
NL7207707A (enExample) 1972-12-20
GB1396156A (en) 1975-06-04
DE2229474A1 (de) 1972-12-21
CA959705A (en) 1974-12-24
NL170469C (nl) 1982-11-01
DE2229474B2 (de) 1975-03-06
DE2229474C3 (de) 1975-10-23
IT956682B (it) 1973-10-10
FR2142366A5 (enExample) 1973-01-26
NL170469B (nl) 1982-06-01

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