US3892175A - Printing needle drive - Google Patents

Printing needle drive Download PDF

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Publication number
US3892175A
US3892175A US370059A US37005973A US3892175A US 3892175 A US3892175 A US 3892175A US 370059 A US370059 A US 370059A US 37005973 A US37005973 A US 37005973A US 3892175 A US3892175 A US 3892175A
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US
United States
Prior art keywords
armature
needle
printing
lever
stroke
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
US370059A
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English (en)
Inventor
Armin Heindke
Gerhard Mutz
Albert Hirt
Werner Winkler
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.)
Digital Kienzle Computersysteme GmbH and Co KG
Original Assignee
Kienzle Apparate GmbH
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
Priority claimed from DE19722230810 external-priority patent/DE2230810C3/de
Application filed by Kienzle Apparate GmbH filed Critical Kienzle Apparate GmbH
Application granted granted Critical
Publication of US3892175A publication Critical patent/US3892175A/en
Anticipated expiration legal-status Critical
Expired - Lifetime 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
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
    • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
    • B41J2/235—Print head assemblies
    • B41J2/25—Print wires
    • B41J2/26—Connection of print wire and actuator
    • 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
    • B41J2/22—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material
    • B41J2/23—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of impact or pressure on a printing material or impression-transfer material using print wires
    • B41J2/27—Actuators for print wires
    • B41J2/285—Actuators for print wires of plunger type

Definitions

  • the lever is preferably resilient, and the mass of the needle is selected so that upon actuation of the armature, the lever is at first slowed down by the mass of the printing needle and then recoils to move at a higher speed than the armature, and to continue in a free stroke when the armature is stopped at the end of the armature stroke.
  • the attaching end portion of the wire which forms the printing needle is wound in a coil around the lever to permit resilient yielding of the printing needle when abutting a printing surface at the end of the needle stroke.
  • the present invention relates to a wire printer or needle printer in which the characters to be printed are formed by a plurality of points printed by printing wires or needles.
  • Matrix printers are known in which, for example, 5 times 7 needles are arranged in lines and columns in the printing head, and selectively operated to form and print the desired character. After a tabulating step, the next character is printed in the same manner.
  • Another wire printer is known in which only seven needles are mounted in the printing head, which are arranged in a column at right angles to the line direction.
  • a character to be printed is formed in several steps of the printing head, the selected printing needles of the columns being operated after each step so that after for example, five steps, a character is completed. After corresponding spacing steps by which the normal spacing between characters is obtained, the printing of the next following character is carried out in the same manner.
  • Modern wire printers of this type use an electromagnet for actuating each printing needle or wire.
  • the electromagnet When the electromagnet is energized, the respective needle is rapidly advanced out of an initial position of rest to a printing position abutting the ink ribbon, and producing imprints on a paper sheet, and if desired on carbon copies, as disclosed, for example, in the German OS 1,943,675.
  • the printing needles or wires are substantially straight, or slightly bent toward the respective electromagnets, and partly guided in guide tubes, so that a rigid connection is formed between the printing surface and the armature of the electromagnet when the printing operation is carried out.
  • This requires an extremely precise adjustment of the printing needle stroke, since otherwise, if the stroke is too long, the ink ribbon and even the paper sheet is perforated, or if the needle stroke is too short, only a weak impression or no impression at all is made. If the needle stroke is far too great, excessive bending and buckling forces are produced, which may cause breakage of the needle. Particularly, at high printing frequencies, the danger of breakage of the needles due to oscillations is great.
  • German AS 1,270,858 discloses a printer of this type in which the printing needle is connected with the armature by a hook and eye connection providing some lost motion. However, this arrangement has not been fully successful.
  • German Pat. No. 1,270,859 discloses an arrangement in which the armature of the electromagnet is tiltable and provided with an elastic arm on which the rear end of the printing needle abuts. Since the arm is elastic, the connection between the armature and the printing needle is not rigid, but the frequency of the needle actuations is substantially reduced because a tiltable armature has a very low efficiency due to the inherently large stray field, as compared with a plunger armature. To compensate this disadvantage a slot and pin connection between the printing needle and the armature is used.
  • Another object of the invention is to combine the high efficiency of an electromagnet with a plunger armature, with transmission of motion from the armature to the printing needle by resilient means.
  • Another object of the invention is to connect the armature with the respective printing needles by a lever in such a manner that the armature stroke is shorter than the printing needle stroke.
  • Another object of the invention is to mount the printing needle on resilient means, so that breakage due to a rigid connection between the armature and the printing needle is avoided.
  • Another object of the invention is to connect an armature by means of a resilient lever with the printing needle to obtain free movement of the printing needle due to elastic recoil when the armature is stopped at the end of its stroke.
  • Another object of the invention is to provide a formlocking connection between the printing wire and the respective armature.
  • an embodiment of the invention comprises lever means having a fulcrum; a printing needle means secured to a first portion of the lever means; electromagnetic means including a movable armature connected with a second portion of the lever means spaced from the fulcrum a smaller distance than the first portion so that when the armature is moved in an armature stroke of predetermined length, the needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than the armature.
  • pivot means are provided at one end of the lever means, the first portion is an end portion located at the other end of the lever means and the armature is connected with the second portion intermediate the ends of the second lever means.
  • the armature is a plunger armature movable in an annular winding and having a portion projecting from the winding and secured to the second portion of the lever means.
  • the lever means is resilient, and the mass of the needle means has such a predetermined magnitude to momentarily prevent movement of the first portion during the first part of the armature stroke by the resilient lever means resiliently deforms and is tensioned so that the lever means recoils during the second part of the armature stroke and accelerates the needle means faster than the armature is accelerated.
  • a stop means is provided for stopping the armature at the end of the armature stroke so that the recoiling resilient lever means continues to move the needle means in a free needle stroke after the stop means has stopped the armature.
  • the printing needle means preferably includes a wire having a projecting printing end portion, and a resilient attaching end portion wound in a coil surrounding the end portion of the lever means.
  • a wire including an intermediate portion between the printing end portion and the coil.
  • the printing end portion is located in an imaginary line passing through the axis of the coil, and the intermediate portion is cranked out of the imaginary line and extends tangentially to the first turn of the coil so that the same spreads when the printing end portion abuts a printing surface.
  • FIG. I is an axial sectional view illustrating an embodiment of a printing needle drive according to the invention.
  • FIG. 2 is a side view illustrating one printing needle
  • FIG. 3 is a plan view illustrating the printing needle of FIG. 2;
  • FIGS. 4a, 4b and 4c are fragmentary sectional views illustrating successive positions of the armature and needle means during a printing operation.
  • an electromagnet 1 includes an annular or tubular winding Ia surrounding a plunger armature 2 and a fixed core I forming a stop a for the axially movable armature 2.
  • a return spring 9 is mounted on a supporting frame 40 and passes through a bore in the end portion 3 of armature 2 so that armature 2 is biased to a position abutting an adjustable screw 4 threaded into the supporting frame 40 and secured by a nut 5.
  • winding la When winding la is energized, the plunger armature is pulled against the action of spring 9 until abutting the stop portion 10a of the fixed core 10.
  • the end portion 3 of armature 2 has a bore 3a through which the portion 6b of the elastic lever 6 passes.
  • a member 7a is secured to one end of lever 6 and carries a pivot pin 7b mounted on a bracket 41 of the supporting means so that lever 6 is turnable about the fulcrum formed by the pivot 7b.
  • the other end of lever 6 has an end portion 6a to which a printing needle 8 is attached by a form-locking connection.
  • the printing needle portion 8b is only partly shown in FIG. 1, and it will be understood that the printing end portions 8b of a plurality of printing needles are combined in a printing head for printing points which together form a character.
  • the printing head has bores for guiding the printing end portions 8b, respectively, during the printing stroke.
  • the armature 2 When the winding la is energized, the armature 2 is drawn into the electromagnet l, tensioning the return spring 9 and moving the lever 6.
  • the downward arma' ture stroke of armature 2 as viewed in the drawing, is limited by the stop portion 10a of the fixed iron core 10, and is preferably 0.4 mm. Since the center portion 6b of lever 6 moves the same distance as the armature 2, its end portion 6a moves a distance of 0.8 mm. taking along the printing needle 8, so that the needle stroke is twice as great than the armature stroke due to the fact that the distance between the armature 3 and the pivot 7b is only half the distance between the lever end portion 6a and the pivot means 7b. In this manner a small armature stroke results in a larger printing stroke of the printing needle 8, and in a high speed of the needle movement. As a result, the armature stroke can be very small, which permits a very high frequency of the armature strokes.
  • the printing needle 8 has a resilient attaching portion which is constituted by a coil 8a formed of the wire which ends in the printing needle 8.
  • the wire of the printing needle 8 is preferably formed as shown in FIGS. 2 and 3, whereupon the coil 8a is pushed onto the free end portion 6a of lever 6, so that the needle 8 is connected with the lever 6 for performing the printing stroke, although removal of the printing needle wire 8 from the end portion 6a is possible in axial direction.
  • the resilient pressure of the coil 8a on the lever end portion 6a secures the printing needle to lever 6.
  • the printing needle 8 preferably has a straight printing needle portion 8b located on an imaginary line 8d passing through the axis of the coil 8a.
  • the intermediate portion 8c is cranked out of the imaginary line 8d, and tangentially connected with the first turn of the coil 8a, as best seen in FIG. 3. Consequently, the first turn of the coil 8a resiliently yields when the leading end of the printing needle 8 impinges the printing surface or the ink ribbon.
  • the resilient mounting of the printing needle 8 on the lever 6 permits the impingement of the printing needle portions 8b on a steel plate, without any damage to the printing needle 8.
  • the lever 6 is a rod consisting of spring steel so that the clasticity of the connection between the driving armature 2, 3 and the printing needle end portion 8 is increased.
  • FIGS. 40, 4b and 4c show the positions of the above described parts during an operation.
  • FIG. 4a shows an initial position of rest in which the end portion 3 of the armature 2 abuts the adjusting screw 4, resilient lever 6 is not deformed, and the jacket ll abuts the damping member I2 which is secured to the supporting frame 3, as also shown in FIG. 1.
  • the inner end of the armature 2 is spaced from the stop portion 104 of core 10.
  • the printing needle 8 with the coil spring 80 and the end portion 6a of the resilient lever 6 move due to inertia in a free movement toward the end of the printing stroke independently of, and beyond the armature strokes. In this manner, a further increase of the needle stroke of the printing stroke of the needle 8 from 0.8 mm. to 1 mm. is obtained.
  • FIGv 4c schematically shows the positions of the parts in the moment of impact of the printing needle on the printing surface.
  • lever 6 Due to the free flight of the printing needle 8 at the end of the printing stroke, lever 6 is tensioned when the printing end portion 8b has impinged on the printing surface, but this time in the opposite direction than before described with reference to FIG. 4b. Due to the elastic tension in lever 6 in the position shown in FIG. 40, after the impinging of the printing needle 8 on the printing surface, the return force of resilient lever 6 is added to the force applied by the return spring 9 on the armature 2, 3 so that the printing needle 8 is further accelerated during the return stroke.
  • a damping member I2 is secured to the supporting means 40 adjacent the end portion 6a of lever 6 and cooperating with the jacket 1] which envelops the coil 80.
  • the stationary damping member 12 which preferably consists of a foam plastic material, or similar damping material.
  • the damping member must be designed and selected to prevent recoil of the armature 2 when its end portion 3 impinges the adjusting screw 4.
  • the printing needle drive of the invention can be advantageously applied to all kinds of modifications of matrix printers, point printers, and other wire printers in which a printing head, guiding a plurality of printing needles, is used for forming characters of printed dots.
  • Printing needle drive comprising supporting means; elongated lever means having a fulcrum mounted on said supporting means and being formed over the whole length thereof from resilient material; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said resilient lever means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said needle means faster than said armature is accelerated when said electromagnet means is energized.
  • said supporting means include pivot means at one end of said lever means for mounting said fulcrum of said lever means; wherein said first portion is an end portion, located at the other end of said lever means; and wherein said armature is connected with said second portion intermediate said ends.
  • said electromagnetic means includes an annular winding; wherein said armature is axially movable in said annular winding and has an armature end portion projecting from said winding and directly secured to said second portion of said lever means.
  • Printing needle drive comprising support means; lever means having a fulcrum mounted on said supporting means and an end portion opposite said fulcrum; printing needle means including a wire having a printing end portion projecting transversely from said end portion of said lever means and a resilient attaching end portion forming a coil tightly surrounding said end portion of said lever means so that printing end portion is resiliently secured to said lever means; an oscillation supressing jacket consisting of synthetic material and enveloping said coil, said end portion in said coil, and a portion of said wire adjacent said coil; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said end portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said arma' ture.
  • said coil has an axis; wherein said wire includes an intermediate portion between said printing end portion and said coil, said printing end portion being straight and being located in an imaginary line passing through said axis of said coil, and said intermediate portion being cranked out of said line and extending tangentially to the first turn of said coil.
  • Printing needle drive comprising supporting means
  • resilient lever means having a fulcrum mounted on said supporting means; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said lever means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said lever means faster than said armature is accelerated when said electromagnet means is energized; and an elongated return spring extending in the general direction of said lever means, abutting in the region of opposite ends thereof against said supporting means,
  • Printing needle drive comprising supporting means; resilient lever means having a fulcrum mounted on said supporting means; printing needle means so cured to a first portion of said lever means and projecting therefrom transversely to said lever means; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said resilient means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said needle means faster than said armature is accelerated when said electromagnet means is energized, said supporting means including stop means for stopping said armature at the end of said armature stroke so that

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US370059A 1972-06-23 1973-06-14 Printing needle drive Expired - Lifetime US3892175A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19722230810 DE2230810C3 (de) 1972-06-23 Antriebsvorrichtung für die Drucknadeln eines Nadeldruckers

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US3892175A true US3892175A (en) 1975-07-01

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US370059A Expired - Lifetime US3892175A (en) 1972-06-23 1973-06-14 Printing needle drive

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US (1) US3892175A (enrdf_load_stackoverflow)
JP (1) JPS5222564B2 (enrdf_load_stackoverflow)
FR (1) FR2190055A5 (enrdf_load_stackoverflow)
GB (1) GB1386530A (enrdf_load_stackoverflow)
IT (1) IT985740B (enrdf_load_stackoverflow)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4000801A (en) * 1973-12-17 1977-01-04 International Business Machines Corporation Print wire attachment
US4242004A (en) * 1979-03-21 1980-12-30 Extel Corporation Dot matrix printhead driver
US4284363A (en) * 1979-07-30 1981-08-18 International Business Machines Corp. Data matrix print head
US4403874A (en) * 1980-03-25 1983-09-13 Ramtek Corporation Color printer and multi-ribbon cartridge therefor
US4569605A (en) * 1984-02-02 1986-02-11 International Business Machines Corporation Wire driving armature for dot printer
US5454649A (en) * 1993-04-28 1995-10-03 Bull Hn Information Systems Italia S.P.A. Wire printhead with armature biasing mechanism
WO1998040642A1 (fr) 1997-03-11 1998-09-17 A.P.S. Engineering S.A.R.L. Ressort de maintien en compression et son application dans un dispositif d'impression compacte

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5190614A (en) * 1975-02-06 1976-08-09 Waiyapurinta nadono waiyakudosochi
JPS586628B2 (ja) * 1975-02-06 1983-02-05 株式会社精工舎 ワイヤプリンタ ナドノ ワイヤクドウソウチ
JPS5262520A (en) * 1975-11-17 1977-05-24 Omron Tateisi Electronics Co Wire dot printer
JPS5270015U (enrdf_load_stackoverflow) * 1975-11-17 1977-05-25
JPS52134511A (en) * 1976-04-30 1977-11-10 Omron Tateisi Electronics Co Dot printer head
JPS579073Y2 (enrdf_load_stackoverflow) * 1976-09-10 1982-02-22
JPS53141719A (en) * 1977-05-13 1978-12-09 Suwa Seikosha Kk Dot printer head
JPS53145726A (en) * 1977-05-25 1978-12-19 Omron Tateisi Electronics Co Wire dot printer

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3099711A (en) * 1961-06-02 1963-07-30 Data Presentations Inc Printing device
US3217640A (en) * 1963-04-30 1965-11-16 Burroughs Corp Electromagnetic actuating means for wire printers
US3266418A (en) * 1963-12-02 1966-08-16 Anelex Corp Print hammer assembly for high speed printers
US3333667A (en) * 1965-12-09 1967-08-01 Teletype Corp Flexible wire guide cable
US3561355A (en) * 1968-03-02 1971-02-09 Telefunken Patent Printing member selector and drive means
US3672482A (en) * 1970-08-31 1972-06-27 Ibm Wire matrix print head
US3770092A (en) * 1972-02-14 1973-11-06 Autotronics Inc Wire print head
US3775714A (en) * 1970-07-06 1973-11-27 Anker Werke Ag Electromagnetic drive for data indication

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3099711A (en) * 1961-06-02 1963-07-30 Data Presentations Inc Printing device
US3217640A (en) * 1963-04-30 1965-11-16 Burroughs Corp Electromagnetic actuating means for wire printers
US3266418A (en) * 1963-12-02 1966-08-16 Anelex Corp Print hammer assembly for high speed printers
US3333667A (en) * 1965-12-09 1967-08-01 Teletype Corp Flexible wire guide cable
US3561355A (en) * 1968-03-02 1971-02-09 Telefunken Patent Printing member selector and drive means
US3775714A (en) * 1970-07-06 1973-11-27 Anker Werke Ag Electromagnetic drive for data indication
US3672482A (en) * 1970-08-31 1972-06-27 Ibm Wire matrix print head
US3770092A (en) * 1972-02-14 1973-11-06 Autotronics Inc Wire print head

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4000801A (en) * 1973-12-17 1977-01-04 International Business Machines Corporation Print wire attachment
US4242004A (en) * 1979-03-21 1980-12-30 Extel Corporation Dot matrix printhead driver
US4284363A (en) * 1979-07-30 1981-08-18 International Business Machines Corp. Data matrix print head
US4403874A (en) * 1980-03-25 1983-09-13 Ramtek Corporation Color printer and multi-ribbon cartridge therefor
US4569605A (en) * 1984-02-02 1986-02-11 International Business Machines Corporation Wire driving armature for dot printer
US5454649A (en) * 1993-04-28 1995-10-03 Bull Hn Information Systems Italia S.P.A. Wire printhead with armature biasing mechanism
WO1998040642A1 (fr) 1997-03-11 1998-09-17 A.P.S. Engineering S.A.R.L. Ressort de maintien en compression et son application dans un dispositif d'impression compacte
FR2760685A1 (fr) * 1997-03-11 1998-09-18 Aps Engineering Ressort de maintien et compression et son application dans un dispositif d'impression compact

Also Published As

Publication number Publication date
FR2190055A5 (enrdf_load_stackoverflow) 1974-01-25
GB1386530A (en) 1975-03-05
DE2230810B2 (de) 1976-11-04
IT985740B (it) 1974-12-20
JPS5222564B2 (enrdf_load_stackoverflow) 1977-06-18
JPS4952534A (enrdf_load_stackoverflow) 1974-05-22
DE2230810A1 (de) 1974-01-10

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