EP0040883B1 - Imprimante par points avec ajustement magnétique de la tête d'impression - Google Patents

Imprimante par points avec ajustement magnétique de la tête d'impression Download PDF

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Publication number
EP0040883B1
EP0040883B1 EP81200546A EP81200546A EP0040883B1 EP 0040883 B1 EP0040883 B1 EP 0040883B1 EP 81200546 A EP81200546 A EP 81200546A EP 81200546 A EP81200546 A EP 81200546A EP 0040883 B1 EP0040883 B1 EP 0040883B1
Authority
EP
European Patent Office
Prior art keywords
carriage
printing head
print
rotation
changing member
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
Application number
EP81200546A
Other languages
German (de)
English (en)
Other versions
EP0040883A3 (en
EP0040883A2 (fr
Inventor
Lothar Haubrich
Wendelin Weber
Heinrich Dürr
Hermann Richter
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.)
Philips Intellectual Property and Standards GmbH
Koninklijke Philips NV
Original Assignee
Philips Patentverwaltung GmbH
Philips Gloeilampenfabrieken NV
Koninklijke Philips Electronics NV
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 Philips Patentverwaltung GmbH, Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Philips Patentverwaltung GmbH
Publication of EP0040883A2 publication Critical patent/EP0040883A2/fr
Publication of EP0040883A3 publication Critical patent/EP0040883A3/de
Application granted granted Critical
Publication of EP0040883B1 publication Critical patent/EP0040883B1/fr
Expired legal-status Critical Current

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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
    • B41J25/00—Actions or mechanisms not otherwise provided for
    • B41J25/001—Mechanisms for bodily moving print heads or carriages parallel to the paper surface

Definitions

  • the invention relates to a matrix printer with a carriage which can be moved back and forth along a paper guide and on which there is a print head which has a plurality of printing positions and can be rotated relative to the carriage about an axis which is perpendicular to the direction of the printing lines and also perpendicular to the plane to be printed of the paper is ventilated, the relative rotation of the print head against the carriage being effected by means of a magnetically activatable position changing element which is carried with the carriage and which exerts a torque on the print head caused by the line movement in its activated state.
  • the position change element consists of a lever which is fastened to the print head close to one end and has a button which can be displaced by means of an electromagnetic drive at its other end.
  • the electromagnetic drive can be done indirectly by means of an adjustable saw toothing which cannot be moved back and forth with the carriage and which engages the head near the turning point of the carriage, or directly by connecting the armature of an electromagnet attached to the carriage the button.
  • a disadvantage of the indirect drive is that when the saw teeth are approached relatively quickly, the button exerts a substantial impact force on the printhead through the saw teeth via the lever.
  • the invention has for its object to provide a matrix printer mentioned above, which greatly reduces the possibility of shock forces of an undesirable size with a relatively quick printhead setting.
  • This object is achieved with a matrix printer according to the invention in that the position change element can be adjusted by means of a braking effect by a magnetic field acting at a specific point on the printing line.
  • a special embodiment of a matrix printer according to the invention in which only a relatively small mass needs to be accelerated and decelerated, is characterized in that the magnetic field is generated by a fixed electromagnet which is connected to the carriage and to that stored in the carriage Position change member slidable parallel to the print line direction, strip-shaped slide from magnetically conductive material cooperates, wherein the position change member and the slide are coupled by means of a pin-slot connection for switching a rotation of the position change member about an axis which runs parallel to the axis of rotation of the print head.
  • a further special embodiment is characterized in that both the axis of rotation of the print head and the axis of rotation of the position change element are located below the print head and the position change element is provided with two pressure elements lying on both sides of the plane through the two axes of rotation, which alternate in pressure-slide contact with one stand flat part which is formed on the printhead.
  • the space above and to the side of the print head is not occupied by components that have to exert the moment on the print head. The space mentioned can therefore be used to arrange other parts of the printer, such as ribbon cassette, ribbon guides, etc.
  • Another embodiment of the matrix printer is characterized in that the carriage and the slide are connected by a dead center spring which has a first stable position corresponding to a first print position of the print head and a second stable position corresponding to a second print position of the print head.
  • the dead center spring ensures simple and inexpensive Way that the mutual positions of the position changing member and the slide corresponding to the first and second pressure positions are stable even when shaken.
  • the matrix printer shown in FIGS. 1, 2 and 3 has a push button 1 for so-called matrix printing.
  • the impression is made by means of electromagnetically driven pressure pens, the printing ends 3 and 5 of which are intended for writing and are located in two columns offset from one another. The distances between two consecutive print ends are the same in the two columns.
  • the two columns with the print ends are vertical.
  • the print ends 5 in the right column are offset from the print ends 3 in the left column by a distance which is equal to half the distance between two successive print ends in the same column.
  • the print head 1 is fastened to a carriage 9 with a wire bracket 7. It is known per se to hook a printhead with a wire bracket of this type onto a carriage.
  • the carriage 9 is moved back and forth in the printing line direction along a paper guide 11 (see FIG. 1) by displacement over a guide profile 13.
  • slide plates 15, 17, 19, 21, 23, 25 and 27 are used (see FIGS. 1 and 3).
  • the guide profile 13 is fastened to two side plates 29 and 31 which belong to the frame of the matrix printer (see FIG. 3).
  • the print head 1 is rotatable relative to the carriage 9 about an axis 33 which runs perpendicular to the line direction and also perpendicular to the plane to be printed.
  • the print head 1 is provided with two pins 35 and 37, which are mounted with their rounded ends in round bearing pans 39 and 41 in the carriage 9.
  • the axis of rotation 33 runs through the pins 35 and 37.
  • a strip-shaped guide 45 is mounted, which is fastened to the carriage 9 (not shown) and is therefore in the Print line direction (parallel to the rib 43) moved with the carriage 9. With the help of the approaches 47 and 49, a strip-shaped slide 51 is guided in the strip-shaped guide 45.
  • the lugs 47 and 49 grip around the top and bottom of the slide 51.
  • An axle stub 53 is mounted in the strip-shaped guide 45 and projects through a window 55 of the slide 51.
  • the stub axle 53 is provided with a head 57 (see FIG. 1). Between the head 57 and the strip-shaped slide 51, a position change member 59 is enclosed, which is rotatable about the stub shaft 53.
  • the center line of the stub shaft 53 is designated by the reference number 61 in FIG. 1 and thus effectively forms the axis of rotation of the position changing member 59.
  • In the slide 51 there is a slot 63 which serves as a slot for a pin 65.
  • the slot 63 lies in a vertical plane and forms an acute angle with a horizontal plane.
  • the pin 65 is part of the position changing member 59 (see Figure 2).
  • the horizontal component (as seen in the printing line direction) of the distance that the pin 65 can travel in the slot 63 is designated by a in FIG. 2.
  • the position change member 59 has two pressure members in the form of cams 67 and 69, which bear against the partially flat underside 70 of the print head 1 and are thus in contact with the pressure slide.
  • the cams 67 and 69 are symmetrical with respect to the axis 33, while the pin 65 lies at the top right in the slot 63.
  • the slide 51 has a widening in the form of an anchor plate 71 which, after the carriage has been moved over a certain distance to the right in the direction of the arrow 73, enters the field 75 of an excited electromagnet 77.
  • the slide 51 is made of magnetically conductive material.
  • the electromagnet 77 is arranged on a frame 79 which is fastened to the side plate 31 and contains a frame 81 in which there is an E-shaped yoke 83 with a core 85, around which an excitation coil 87 is arranged.
  • the center line 89 of the excitation coil 87 runs perpendicular to the plane of the armature plate 71.
  • In the side plate 31 there is an opening 91 through which the slide 51 projects.
  • the electromagnet 77 is excited by the supply of an electrical voltage U to the excitation coil 87. This is done via a switching transistor 93, the base of which is connected to a logic AND gate 94 with two inputs.
  • One input of the logic AND gate is connected to control electronics 95 of the matrix printer, which generates a signal with the value "1" when the carriage 9 is reversed while the other input of the logic AND gate is connected to an external signal transmitter, which generates a pulse 97 with the value "1" when the printhead 1 is to be rotated about the axis 33 after the movement reversal.
  • Rotation of the print head 1 about the axis 33 is effected as follows. At the time of braking the movement of the carriage 9 to the right in the direction of the arrow 73 to a speed of the carriage 9 equal to zero and when starting to accelerate the carriage to the left, the control electronics 95 generates a signal with the value "1" at one input of the logic AND gate 94. If printhead twist due to a desired high print speed, an external signal generator generates a pulse 95 with the value "1" at the other input of the logic AND gate 94. The output of the logic AND gate 94 now generates an electrical voltage at the base of the switching transistor 93 with such Value that the switching transistor 93 becomes conductive so that the excitation coil 87 carries the voltage U for the duration of the pulse 97.
  • the armature plate 71 is in the field 75 and is held in this field for a short time after the reversal of the movement of the carriage 9 and when the carriage 9 is accelerated to the left.
  • the duration of the pulse 97 is such that the pin 65 which moves with the carriage 9 experiences a displacement a in the horizontal direction relative to the slot 63 which is located in the slide 51 held in the magnetic field 75.
  • the field 75 exerts a braking effect on the slide 51, as it were.
  • the position change member 59 rotates about the stub shaft 53 or about the axis of rotation 61, so that a pressure force is exerted on the print head 1 at the location of the cam 69.
  • the print head 1 thereby rotates about the axis 33 through a certain angle, which is determined by the abutment of the pin 65 in the bottom left slot 63.
  • In the carriage 9 there is also a contact surface for the print head 1 which is not visible in the figures.
  • the pin 65 is attached to the bottom left by means of a wire spring 99 which is attached to the slide 51 at one end 101 and to the carriage 9 at its other end 103 held in slot 63.
  • the pin 65 Due to the wire spring 99 working as a dead center spring, the pin 65 is pretensioned at the left end of the slot 63.
  • the wire spring 99 is in a first stable position.
  • the wire spring 99 prevents unwanted relative movement between the pin 65 and the slot 63 from shocks.
  • the pulse 97 and therefore also the excitation of the electromagnet 77 are terminated at the time or shortly after the time at which the pin 65 contacts the left end of the slot 63.
  • the force exerted by the magnetic field 75 on the armature plate 71 of the slide 51 is never so great that an excessively long duration of the pulse 97 could damage the pin 65.
  • the field 75 acts like a slip clutch on the slide 51.
  • the distance between the axes of rotation 33 and 61 is equal to 20 mm.
  • the center-to-center distance between print ends 3 or 5 of the same column is 0.36 mm, while the center-to-center distance between the two columns with print ends is 2.117 mm.
  • the two columns with printing ends were in a mutually offset position (seen in the vertical direction).
  • This offset position characters with a maximum of ten printed dots can be printed in the vertical portion of a character.
  • the vertical distance between the printed dots is therefore relatively small, i. H. 0.18 mm.
  • the print head 1 was rotated through an angle of approximately 5 °.
  • the corresponding print ends 3 and 5 of the two columns are vertically on the same level.
  • the vertical distance between the printed dots is now 0.36 mm.
  • the invention is not limited to designs of matrix printers in which the print head can only be rotated when the movement is reversed on the right side.
  • the symmetrical design of the slide 51 with an anchor plate 71 at each end and the arrangement of an electromagnet on the left-hand side make it possible to rotate the print head each time the movement is reversed.
  • an electromagnet which moves with the carriage 9 in connection with a fixed strip of magnetically conductive material which extends along the entire distance of the carriage 9.
  • a permanent magnet can also be used instead of an electromagnet. He can both be firmly arranged as well as move with the carriage 9.
  • the magnetic braking effect can also be exerted directly on the position change member 59 without the intermediary of a slide 51.
  • the position change member 59 consists at least partially of magnetically conductive material.
  • the invention is also not limited to matrix printers with print heads, in which the printing elements are formed by electromagnetically driven printing pins.
  • any type of printhead suitable for matrix printing can be used, for example a printhead in which drops of ink are created which are applied to the paper through tubes. It is also worth mentioning that if a printhead with only one column of printing elements is used, the printing elements are printed on a first level in a first pass of the printhead and on a second level in a second pass after the printhead has been rotated through, for example, 10 ° Completion of the characters already partially printed during the first pass.

Landscapes

  • Character Spaces And Line Spaces In Printers (AREA)
  • Impact Printers (AREA)
  • Common Mechanisms (AREA)
  • Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)
  • Printers Characterized By Their Purpose (AREA)

Claims (5)

1. Imprimante matricielle comportant un chariot (9) pouvant se déplacer dans un sens et dans l'autre le long d'un guide (11) popur le papier, sur lequel se trouve une tête d'impression (1) qui présente plusieurs positions d'impression et qui peut à cet effet pivoter autour d'un axe par rapport au chariot (9), cet axe s'étendant perpendiculairement à la direction des lignes d'impression (73) et, en outre, perpendiculairement au plan du papier à imprimer, le pivotement relatif de la tête d'impression (1) par rapport au chariot (9) s'effectuant au moyen d'un organe de changement de position (59) accompagnant le chariot (9), qui peut être activé magnétiquement et qui impose à la tête d'impression (1) un moment de pivotement provoqué par le déplacement des lignes dans son état activé, caractérisée en ce que l'organe de changement de position (59) peut être réglé au moyen de l'effet de freinage produit par un champ magnétique (75) agissant en un endroit déterminé de la ligne d'impression.
2. Imprimante matricielle suivant la revendication 1, caractérisée en ce que le champ magnétique (75) est produit par un électroaimant fixe qui coopère avec un coulisseau en forme de bande (51) en matière magnètiquement conductrice qui peut coullisser par rapport au chariot (9) et à l'organe de changement de position (59) monté dans le chariot, parallèlement à la direction des lignes d'impression (73), l'organe de changement de position et le coulisseau étant couplés l'un à l'autre au moyen d'une liaison à ergot et boutonnière (65, 63) pour faire pivoter l'organe de changement de position autour d'un axe (61), qui s'étend parallèlement à l'axe de pivotement (33) de la tête d'impression (1 ).
3. Imprimante matricielle suivant la revendication 2, caractérisé en ce que l'axe de pivotement (33) de la tête d'impression (1), ainsi que l'axe de pivotement (61) de l'organe de changement de position (59) se trouvent tous deux en dessous de la tête d'impression et que l'organe de changement de position est pourvu de deux organes de pression (68, 69) disposés de part et d'autre du plan passant par les deux axes de pivotement, ces organes de pression étant en alternance en contact de glissement sous pression avec une partie plane qui est formée sur la tête d'impression.
4. Imprimante matricielle suivant la revendication 2, caractérisée en ce que le chariot (9) et le coulisseau (51) sont reliés l'un à l'autre par un ressort de point mort (99) qui présente une première position stable correspondant à une première position d'impression de la tête d'impression (1) et une deuxième position stable correspondant à une deuxième position d'impression de la tête d'impression.
5. Imprimante matricielle suivant la revendication 1, caractérisée en ce que la tête d'impression (1) contient deux colonnes d'éléments d'impression décalées l'une par rapport l'autre, dont les extrémités d'impression (3, 5) sont disposées à égale distance d'un plan perpendiculairement à la direction des lignes, le plan passant, dans une des positions d'impression de la tête d'impression, par l'axe de pivotement (61) de l'organe de changement de position (59).
EP81200546A 1980-05-23 1981-05-21 Imprimante par points avec ajustement magnétique de la tête d'impression Expired EP0040883B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3019773 1980-05-23
DE19803019773 DE3019773A1 (de) 1980-05-23 1980-05-23 Drucker zur herstellung eines rasterfoermig aufgebauten zeichens

Publications (3)

Publication Number Publication Date
EP0040883A2 EP0040883A2 (fr) 1981-12-02
EP0040883A3 EP0040883A3 (en) 1982-03-17
EP0040883B1 true EP0040883B1 (fr) 1985-01-02

Family

ID=6103174

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81200546A Expired EP0040883B1 (fr) 1980-05-23 1981-05-21 Imprimante par points avec ajustement magnétique de la tête d'impression

Country Status (9)

Country Link
US (1) US4475826A (fr)
EP (1) EP0040883B1 (fr)
JP (1) JPS5718271A (fr)
BR (1) BR8103130A (fr)
CA (1) CA1171317A (fr)
DE (2) DE3019773A1 (fr)
FI (1) FI69598C (fr)
IE (1) IE51401B1 (fr)
YU (1) YU130781A (fr)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3313205C1 (de) * 1983-04-12 1984-10-04 Siemens AG, 1000 Berlin und 8000 München Vorrichtung zur Fuehrung einer Druckwerkes
US4874264A (en) * 1983-05-12 1989-10-17 Ricoh Company, Ltd. Selective magnetic attachment of a print head to a drive belt
DE3832670A1 (de) * 1988-09-27 1990-03-29 Philips Patentverwaltung Druckkopf fuer einen matrixdrucker
JPH0720723B2 (ja) * 1988-12-09 1995-03-08 株式会社精工舎 印字ヘッドの取付構造
JP2522231B2 (ja) * 1991-11-15 1996-08-07 株式会社精工舎 印字モ―ドを切換え可能なワイヤドットプリンタ
US5368403A (en) * 1993-04-30 1994-11-29 Hewlett-Packard Company Carriage support system for computer driven printer

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4059182A (en) * 1973-12-20 1977-11-22 U.S. Philips Corporation Mosaic printer
SE378922B (fr) * 1973-12-20 1975-09-15 Philips Svenska Ab
FR2291035A1 (fr) * 1974-11-14 1976-06-11 Sagem Perfectionnements apportes aux dispositifs d'impression d'informations d'un premier et d'un second types qui comprennent au moins une tete d'impression
US4010835A (en) * 1975-08-01 1977-03-08 International Business Machines Corporation Matrix print head
DD128153A1 (de) * 1976-08-26 1977-11-02 Volker Flechtner Mosaikdruckkopf

Also Published As

Publication number Publication date
CA1171317A (fr) 1984-07-24
YU130781A (en) 1984-02-29
IE51401B1 (en) 1986-12-24
DE3168019D1 (en) 1985-02-14
IE811122L (en) 1981-11-23
US4475826A (en) 1984-10-09
FI811555L (fi) 1981-11-24
JPS5718271A (en) 1982-01-30
DE3019773A1 (de) 1981-12-03
EP0040883A3 (en) 1982-03-17
FI69598C (fi) 1986-03-10
JPH0251737B2 (fr) 1990-11-08
FI69598B (fi) 1985-11-29
BR8103130A (pt) 1982-02-09
EP0040883A2 (fr) 1981-12-02

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