EP0000413B1 - Drive mechanism for printers, either for progressing or reversing an ink ribbon, or for retracting the printing head - Google Patents

Drive mechanism for printers, either for progressing or reversing an ink ribbon, or for retracting the printing head Download PDF

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Publication number
EP0000413B1
EP0000413B1 EP78200075A EP78200075A EP0000413B1 EP 0000413 B1 EP0000413 B1 EP 0000413B1 EP 78200075 A EP78200075 A EP 78200075A EP 78200075 A EP78200075 A EP 78200075A EP 0000413 B1 EP0000413 B1 EP 0000413B1
Authority
EP
European Patent Office
Prior art keywords
lever
gearwheels
ribbon
gear
control
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
EP78200075A
Other languages
German (de)
French (fr)
Other versions
EP0000413A1 (en
Inventor
Manfred Adamek
Horst Würscher
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
Priority claimed from DE19772731593 external-priority patent/DE2731593C3/en
Priority claimed from DE19772731607 external-priority patent/DE2731607C3/en
Application filed by Philips Patentverwaltung GmbH, Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Philips Patentverwaltung GmbH
Publication of EP0000413A1 publication Critical patent/EP0000413A1/en
Application granted granted Critical
Publication of EP0000413B1 publication Critical patent/EP0000413B1/en
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
    • B41J23/00—Power drives for actions or mechanisms
    • B41J23/02—Mechanical power drives
    • B41J23/025—Mechanical power drives using a single or common power source for two or more functions
    • 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
    • B41J33/00—Apparatus or arrangements for feeding ink ribbons or like character-size impression-transfer material
    • B41J33/14—Ribbon-feed devices or mechanisms
    • B41J33/40—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction
    • B41J33/44—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction automatically
    • B41J33/51—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction automatically and characterised by the use of particular reversing control means
    • B41J33/518—Ribbon-feed devices or mechanisms with arrangements for reversing the feed direction automatically and characterised by the use of particular reversing control means the reversing-feeler engaging buttons or the like secured to the ribbon near its ends

Definitions

  • the invention relates to a drive device for the transport or switching of an ink ribbon as required and for pivoting the print head from the print abutment in printing devices of a typewriter or booking machine, in which the ink ribbon is switched and transported by gears which are firmly connected to one another via a control shaft and which are moved longitudinally the switching shaft alternately come into engagement in the associated sprockets of the bobbin arranged on the side of the printing device, and in which the swiveling of the printhead takes place by tensioning a pulling rope which is guided on one side of the printing device and on the other * deflection rollers past the printhead.
  • each spool is assigned a gear, in particular worm gear. These two gears are connected to each other via a selector shaft, which is slidably mounted.
  • the selector shaft actuated by a motor via a gear transmission is moved further in the previous direction, so that a force is exerted in the longitudinal direction of the selector shaft via the driving worm wheel. This force causes a displacement of the shaft as soon as it is greater than the force of a dead center switching device which prevents this displacement.
  • the electric motor required for this drive device always rotates in the same direction.
  • a pivoting device in which a traction cable is used, which is fastened on one side of the printing device, while it is connected to a pivoting lever on the other side.
  • the traction cable is deflected by at least three rollers, two of which are on the side of the printhead on the carriage and one in the direction of the platen on the printhead are stored. If the swivel lever is actuated, the rope is tightened and the roller located on the print head is pulled in the direction of the plane formed by the two rollers of the carriage.
  • an electric motor is provided which is switched as required.
  • the invention has for its object to provide a device that can be used both for driving a transport and switching device for the ribbon and for pulling the printing unit, so that only one electric motor is provided for both types of drive and in which the Conversion required ribbon tension forces are as low as possible and the structure is simple. It is assumed that both types of drive do not take effect at the same time, because in typewriters and booking machines, a write process is never carried out with the print head swung down.
  • one of the gearwheels interacting with the sprockets of the coil carrier is constantly in operative connection via a directional lock with a common drive axis in that the pivoting lever holding the pull rope at its free end rolls on an eccentric cam disk of a half-speed clutch, which A further directional lock is in operative connection with the common drive axle, that both directional locks lock in opposite directions and that the common drive axle can be driven reversibly by a single electric motor.
  • the drive axis is expediently reversed by electrical switching of the electric motor. But it can also be done via a change gear, so that the electric motor is constantly rotating in the same direction.
  • the electrical control of the electric motor is technically simpler and can easily be derived from the half-speed clutch via switching devices. Since the half-speed clutch is freely supported on the common drive axle during transport and a changeover of the ink ribbon, it is advisable to provide the half-speed clutch with a second cam disc with two approximately diametrically opposed recesses, in which a fixing lever for locking the two end positions of the pivoting lever can be locked .
  • the interconnected gears and the coil carriers assigned to them are expediently provided with conical projections, the conical surfaces of which are each directed towards one another and rub against one another in the opposite direction of rotation, as long as the Gears and the associated sprockets are disengaged. If the two assigned gears are disengaged after switching the transport direction of the ribbon, the sprockets of the gears connected to one another are freely movable in grooves, which are each arranged between the sprocket and the conical shoulder of the bobbin. Since these non-intermeshing sprockets are driven in opposite directions on the one hand by the drive device and on the other hand by the ink ribbon, both conical projections grind against one another. As a result, the drawn bobbin is braked and the unwinding ribbon is kept taut.
  • a gear lever is assigned to each gear on the selector shaft, which is pivoted by the ribbon against the end face of the assigned gear, that at least one of these shift levers is assigned a roller lever that can be moved against a spring force, and that the rolling plane is in the area of action of this roller lever of the shift lever has a roof-shaped cross section.
  • Both shift levers are expediently rigidly connected to one another.
  • the length of the run-up slope of the roof-shaped rolling plane is somewhat smaller than the distances between the shift levers and the associated gear wheels.
  • the shift levers are provided with lugs.
  • the printing device shown in the drawings consists of the housing walls 36 and 361, which are connected to one another by the spacer rails 27 and 28.
  • the pressure abutment 53 and the sliding blocks for the transport carriage 56 of the print head 49 are fastened.
  • the hollow shaft 10 is also fixed, in which the control shaft 8 is rotatably and slidably mounted.
  • Gears 7 and 9 are fixedly arranged on the ends of the selector shaft 8 projecting beyond the housing walls. These gear wheels 7 and 9 alternately engage with gear rings 141 and 131 assigned to them by shifting the selector shaft 8.
  • These sprockets are part of assigned spool supports 13 and 14, on the mandrels 16 and 29 of which the ribbon spools 11 and 12 are attached.
  • the ribbon spools 11 and 12, which mostly consist of sheet metal, are held by permanent magnets 15 (shown only on one side).
  • the ink ribbon 17 is guided over the rear deflection rollers 55 and 551 and over the front deflection rollers 54 and 541 on the front side of the print head 49. All pulleys are stored on the removable print head.
  • Both gear wheels 7 and 9 and both coil carriers 13 and 14 have conical projections 71, 91 or 132 and 142, the conical surfaces of which are directed towards one another.
  • the tapered surfaces 71 and 142 of the gear 7 and the associated ring gear 141 come into contact with each other when the gear and ring gear are out of engagement after the switching process.
  • the gear 9 and ring gear 131 are in engagement with one another, and the conical surfaces 91 and 132 are not in contact with one another.
  • the gear 7 and the ring gear 141 are disengaged, while the conical surfaces 71 and 142 touch. If the control shaft 8 is driven via the gear 7, the spool 13 and thus the ribbon reel 11 are driven via the gear 9.
  • the ink ribbon 17 is thereby rewound from the ink ribbon spool 12 to the ink ribbon spool 11.
  • the gear 7 and the coil carrier 14 make opposite rotational movements, so that the surfaces of the cones 71 and 142 rub against each other.
  • This frictional force exerts a force on the ribbon spool 12 against the unwinding direction, which causes the ribbon 17 to be tightened continuously.
  • this tightening is achieved by the frictional forces between the bevel gears 91 and 132.
  • the shift of the control shaft 8 and thus the switching of the transport direction of the ink ribbon 17 is described in more detail below with reference to FIG. 4.
  • a Gear consisting of the gears 3, 4 and 5 is mounted on the housing side wall 36.
  • This gear is driven by the gear 2 of an electric motor 1, which is attached to the housing wall 36.
  • the gear wheel 5 is fastened on a drive shaft 37 which is mounted in the housing wall 36 and the angular support 35.
  • This axis 37 is the common drive axis for the ribbon transport and the pivoting of the print head.
  • a gear 6 is arranged on the axis 37, which is driven by a directional lock 65 from the shaft 37 and which is constantly in operative connection with the gear 7.
  • the locking direction of the directional lock 65 is selected so that when the common axis 37 is driven by the electric motor 1 in one direction the driving force is transmitted to the gear 7, but not when the axis 37 is rotating in the opposite direction.
  • the drive shaft 37 which is rotatably arranged in the housing wall 36 in the bearing 39, is extended beyond the bearing point 38 in the angle bracket 35 and bears the curved part of a half-speed clutch on this extension.
  • This curve piece is mounted on a directional lock 44 on this common drive shaft 37, the locking direction of which is opposite to the locking direction of the locking mechanism 65. This means that when the directional lock 65 is locked, the directional lock 44 is not locked. If, however, the directional lock 65 is free-running, the directional lock 44 locks and thus transmits the driving force emanating from the electric motor 1 to the half-speed clutch.
  • the half-speed clutch has two cams 40 and 59. With both cams, two levers 43 and 58 are controlled, which are mounted on a common axis of rotation 57.
  • the lever 43 is connected at one end to the housing wall 36 via a spring 66 and, as a result of this spring force, engages with its support roller 61 in recesses in the cam plate 59. These recesses are approximately diametrically opposite and cause the half-speed clutch to be locked in the two end positions of the pivoting lever 58, which is pivoted back and forth with the support roller on the cam disk 40 about the pivot point 57.
  • This pivoting lever 58 has a shoulder 52 to which the pull cable 46 is fastened at one end.
  • the cable is deflected to the print head 49 via a deflection roller 51 and fastened to a leaf spring 45 on the other side of the printing device, which in turn is firmly connected to the housing wall 361. With the aid of the adjusting screw 63, length tolerances of the rope 46 can be compensated for.
  • the rope 46 is steered via three deflection rollers 47, 48 and 50.
  • the rollers 47 and 48 are mounted on the carriage 56, while the roller 50 is attached to the front part of the print head 49.
  • the electric motor 1 is excited again and the half-speed clutch is rotated a further half turn via the directional lock 44.
  • the microswitch 42 is actuated, which now initiates a reversal of the electric motor.
  • the pivot lever 58 will again assume its position shown in FIG. 3 and loosen the cable 46. Due to a spring force, not shown, the print head 49 is moved in the direction of the platen 53.
  • the directional ratchet 65 After reversing the electric motor 1, the directional ratchet 65 now becomes effective by reversing the direction of the drive axis 37 and thus also the ribbon transport or, if necessary, the ribbon switch.
  • the ribbon 17 has, as shown in Fig. 4, at both ends of the eyelets 18 through which the respective associated shift levers 19 and 20 are pivoted.
  • the shift levers 19 and 20 are pivotally mounted in bearings 21 and 22 on the housing walls 36 and 361. At one end they are rigidly coupled to one another by a connecting rod 23. I.e. they always make the same movements. At their other ends, the shift levers 19 and 20 are provided with fork-shaped projections 30 and 31 through which the ribbon 17 slides.
  • a roller lever is additionally arranged displaceably on the housing wall 36.
  • the displacement of the roller lever is directed perpendicular to the control shaft 8 within the plane of the drawing.
  • the roller lever 24 In its drawn rest position, the roller lever 24 is held by the force of a tension spring 25.
  • the side edge of the lever 19 is roof-shaped.
  • the rolling plane 34 for the roller lever 24 thus consists of one Run-up slope 341 and a run-off slope 342.
  • the shift lever 20 is also formed with these slopes in the present exemplary embodiment. This is only for manufacturing reasons, since in this way both shift levers 19 and 20 are the same stamped parts.
  • the shift levers 19 and 20 have lugs 26 and 33, which rest in the operative position of the shift levers 19 and 20 on the gears 7 and 9 and are lifted from the latter in the rest position.
  • the position of the shift lever 20 shown on the right in FIG. 4 thus represents the active position, while the position of the shift lever 19 shown on the left in FIG. 4 is the rest position.
  • the restraining eye 18 strikes the shoulder 31 of the shift lever 19 and takes it along in the direction of the arrow.
  • the roller lever 24 is pushed upward against the force of the spring 25 until the roller lever has exceeded the upper tip of the roof-shaped rolling plane 34.
  • the approach 33 comes to rest on the gear 7 after covering the path 32.
  • a force is exerted on the gear 7 by the attachment 33, which acts axially to the shift shaft 8 and shifts it.
  • the toothed wheel 7 is now in engagement with the toothed ring 141.
  • the ink ribbon 17 is thereby moved in the opposite direction of the arrow.
  • the shift lever 19 remains in its working position, in which the roller lever 24 is located on the run-off slope 342 of the rolling plane 34. If the ink ribbon 17 is unwound in the opposite direction of the arrow, the locking eyelet located at the right end of the ink ribbon, shown in FIG. 1, appears in the region of the fork 30 of the lever 20. As a result, the lever 20 is now pivoted in the manner previously described until the shoulder 26 rests on the gear 9.
  • the shift lever 19 has also been pivoted by the same amount and the roller lever 24 has been raised against the force of the spring 25 over the top of the roof-shaped rolling plane 34.
  • the spring force of the spring 25 acts on the lever 19 and via the connecting rod 23 on the shift lever 20, which now shifts the shift shaft 8 to the left.
  • the ramp slope 341 seen from the roof top must be slightly smaller than the distance 32 between the shoulder 33 of the shift lever 19 and the gear 7 and that the length of the ramp slope 342 seen from the roof tip must be somewhat smaller than the distance of the extension 26 of the shift lever 20 to the gear wheel 9.
  • the distance from the roof top of the rolling plane 34 to the support point of the roller lever 23 is to be understood in the two positions.

Landscapes

  • Impression-Transfer Materials And Handling Thereof (AREA)
  • Character Spaces And Line Spaces In Printers (AREA)

Description

Antriebsvorrichtung zum bedarfsweisen Transport bzw. Umschalten eines Farbbandes und zum Abschwenken des Druckkopfes in Druckeinrichtungen
Die Erfindung betrifft eine Antriebsvorrichtung zum bedarfsweisen Transport bzw. Umschalten eines Farbbandes und zum Abschwenken des Druckkopfes vom Druckwiderlager in Druckeinrichtungen einer Schreib- oder Buchungsmaschine, bei der die Umschaltung und der Transport des Farbbandes durch fest über eine Schaltwelle miteinander verbundenen Zahnrädern erfolgt, die durch Längsverschiebung der Schaltwelle wechselweise in zugeordnete Zahnkränze der seitlich der Druckeinrichtung angeordneten Spulenträger in Eingriff kommen, und bei der die Abschwenkung des Druckkopfes durch Straffung eines Zugseiles erfolgt, das auf der einen Seite der Druckeinrichtung und auf der anderen*Umlenkrollen am Druckkopf vorbeigeführt ist.Drive device for transporting or switching an ink ribbon as required and for pivoting the print head in printing devices
The invention relates to a drive device for the transport or switching of an ink ribbon as required and for pivoting the print head from the print abutment in printing devices of a typewriter or booking machine, in which the ink ribbon is switched and transported by gears which are firmly connected to one another via a control shaft and which are moved longitudinally the switching shaft alternately come into engagement in the associated sprockets of the bobbin arranged on the side of the printing device, and in which the swiveling of the printhead takes place by tensioning a pulling rope which is guided on one side of the printing device and on the other * deflection rollers past the printhead.

* Seite an einem Schwenkhebel befestigt und über * Side attached to a swivel lever and over

Aus der DE-OS 19 23 498 ist eine Vorrichtung zum Transport bzw. Umschalten eines Farbbandes bekannt, bei der jedem Spulenträger ein Zahnrad, insbesondere Schneckenrad zugeordnet ist. Diese beiden Zahnräder sind über eine Schaltwelle miteinander verbunden, die verschiebbar gelagert ist. Ist das Farbband abgespult, so wird eine weitere Bewegung des Farbbandes durch die leere Spule gestoppt. Die über ein Zahnradgetriebe von einem Motor betätigte Schaltwelle wird in der bisherigen Richtung weiterbewegt, so daß über das antreibende Schneckenrad eine Kraft in Längsrichtung der Schaltwelle ausgeübt wird. Diese Kraft bewirkt eine Verschiebung der Welle, sobald sie größer ist als die diese Verschiebung an sich verhindernde Kraft einer Totpunktschaltvorrichtung. Der für diese Antriebsvorrichtung benötigte Elektromotor dreht dabei stets in ein und derselben Richtung.From DE-OS 19 23 498 a device for transporting or switching an ink ribbon is known, in which each spool is assigned a gear, in particular worm gear. These two gears are connected to each other via a selector shaft, which is slidably mounted. Once the ribbon has been unwound, further movement of the ribbon through the empty spool is stopped. The selector shaft actuated by a motor via a gear transmission is moved further in the previous direction, so that a force is exerted in the longitudinal direction of the selector shaft via the driving worm wheel. This force causes a displacement of the shaft as soon as it is greater than the force of a dead center switching device which prevents this displacement. The electric motor required for this drive device always rotates in the same direction.

Bei Schreib- und Buchungsmaschinen ist es weiterhin bekannt, den Druckkopf vom Druckwiderlager abzuziehen, um dadurch ein leichteres Einführen der zu beschreibenden Aufzeichnungsträger zu ermöglichen. So ist eine Abschwenkvorrichtung bekannt, bei der ein Zugseil verwendet wird, das auf der einen Seite der Druckeinrichtung befestigt ist, während es auf der anderen Seite mit einem Schwenkhebel verbunden ist. Im Bereich des Druckkopfes, der auf einem längs des Druckwiderlagers bewegbaren Wagen senkrecht zum Druckwiderlager verschiebbar gelagert ist, wird das Zugseil von mindestens drei Rollen umgelenkt, von denen zwei seitlich des Druckkopfes auf dem Wagen und eine in Richtung auf das Druckwiderlager versetzt dazu auf dem Druckkopf gelagert sind. Wird der Schwenkhebel betätigt, so wird das Seil gestrafft und dadurch die auf dem Druckkopf befindliche Rolle in Richtung auf die von den beiden Rollen des Wagens gebildete Ebene gezogen.In the case of typewriters and booking machines, it is also known to pull the printhead away from the printing abutment in order thereby to make it easier to insert the record carriers to be written on. A pivoting device is known in which a traction cable is used, which is fastened on one side of the printing device, while it is connected to a pivoting lever on the other side. In the area of the printhead, which is mounted on a carriage that can be moved along the platen perpendicular to the platen, the traction cable is deflected by at least three rollers, two of which are on the side of the printhead on the carriage and one in the direction of the platen on the printhead are stored. If the swivel lever is actuated, the rope is tightened and the roller located on the print head is pulled in the direction of the plane formed by the two rollers of the carriage.

Zur Steuerung des Schwenkhebels ist ein Elektromotor vorgesehen, der bedarfsweise geschaltet wird.To control the swivel lever, an electric motor is provided which is switched as required.

Der Erfindung liegt die Aufgabe zugrunde, eine Vorrichtung zu schaffen, die sowohl zum Antrieb einer Transport- und Umschalteinrichtung für das Farbband als auch zum Abziehen des Druckwerkes bedarfsweise verwendet werden kann, so daß für beide Antriebsarten nur ein Elektromotor vorzusehen ist und bei der die zur Umkehrung erforderlichen Farbbandspannkräfte möglichst gering sind und die in ihrem Aufbau einfach gestaltet ist. Dabei wird davon ausgegangen, daß beide Antriebsarten nicht gleichzeitig wirksam werden, denn in Schreib- und Buchungsmaschinen wird ein Schreibvorgang niemals bei abgeschwenktem Druckkopf vorgenommen.The invention has for its object to provide a device that can be used both for driving a transport and switching device for the ribbon and for pulling the printing unit, so that only one electric motor is provided for both types of drive and in which the Conversion required ribbon tension forces are as low as possible and the structure is simple. It is assumed that both types of drive do not take effect at the same time, because in typewriters and booking machines, a write process is never carried out with the print head swung down.

Diese Aufgabe wird in vorteilhafter Weise dadurch gelöst, daß eines der mit den Zahnkränzen der Spulenträger zusammenwirkenden Zahnräder ständig über ein Richtgesperre mit einer gemeinsamen Antriebsachse in Wirkverbindung steht, daß der das Zugseil an seinem freien Ende haltende Abschwenkhebel auf einer exzentrischen Kurvenscheibe einer Halbtourenkupplung abrollt, die über ein weiteres Richtgesperre mit der gemeinsamen Antriebsachse in Wirkverbindung steht, daß beide Richtgesperre in entgegengesetzten Richtungen sperren und daß die gemeinsame Antriebsachse von einem einzigen Elektromotor reversierbar antreibbar ist. Die Reversierung der Antriebsachse erfolgt zweckmäßig durch elektrische Umschaltung des Elektromotors. Sie kann aber auch über ein Wechselgetriebe erfolgen, so daß der Elektromotor ständig in gleicher Richtung dreht. Die elektrische Steuerung des Elektromotors ist technisch einfacher und läßt sich über Schaltvorrichtungen von der Halbtourenkupplung ohne weiteres ableiten. Da die Halbtourenkupplung während des Transportes und einer Umschaltung des Farbbandes frei auf der gemeinsamen Antriebsachse lagert, ist es zweckmäßig, die Halbtourenkupplung mit einer zweiten Kurvenscheibe mit zwei annähernd diametral gegenüberliegenden Vertiefungen zu versehen, in denen ein Fixierhebel zur Arretierung der beiden Endlagen des Abschwenkhebels einrastbar ist.This object is achieved in an advantageous manner in that one of the gearwheels interacting with the sprockets of the coil carrier is constantly in operative connection via a directional lock with a common drive axis in that the pivoting lever holding the pull rope at its free end rolls on an eccentric cam disk of a half-speed clutch, which A further directional lock is in operative connection with the common drive axle, that both directional locks lock in opposite directions and that the common drive axle can be driven reversibly by a single electric motor. The drive axis is expediently reversed by electrical switching of the electric motor. But it can also be done via a change gear, so that the electric motor is constantly rotating in the same direction. The electrical control of the electric motor is technically simpler and can easily be derived from the half-speed clutch via switching devices. Since the half-speed clutch is freely supported on the common drive axle during transport and a changeover of the ink ribbon, it is advisable to provide the half-speed clutch with a second cam disc with two approximately diametrically opposed recesses, in which a fixing lever for locking the two end positions of the pivoting lever can be locked .

Die miteinander verbundenen Zahnräder und die diesen zugeordneten Spulenträger sind zweckmäßig mit kegelförmigen Ansätzen versehen, deren Kegelflächen jeweils zueinander gerichtet sind und bei gegenläufiger Drehrichtung aufeinander schleifen, solange die Zahnräder und die zugeordneten Zahnkränze außer Eingriff sind. Werden nach Umschaltung der Transportrichtung des Farbbandes die beiden zugeordneten Zahnräder außer Eingriff gebracht, so sind die Zahnkränze der miteinander verbundenen Zahnräder in Nute frei beweglich, die jeweils zwischen dem Zahnkranz und deren kegelförmigem Ansatz der Spulenträger angeordnet sind. Da diese nicht miteinander in Eingriff stehenden Zahnkränze gegenläufig einerseits von der Antriebsvorrichtung und andererseits vom Farbband angetrieben werden, schleifen beide kegelförmigen Ansätze aufeinander. Hierdurch wird der gezogene Spulenträger gebremst und das sich abspulende Farbband ständig gestrafft gehalten.The interconnected gears and the coil carriers assigned to them are expediently provided with conical projections, the conical surfaces of which are each directed towards one another and rub against one another in the opposite direction of rotation, as long as the Gears and the associated sprockets are disengaged. If the two assigned gears are disengaged after switching the transport direction of the ribbon, the sprockets of the gears connected to one another are freely movable in grooves, which are each arranged between the sprocket and the conical shoulder of the bobbin. Since these non-intermeshing sprockets are driven in opposite directions on the one hand by the drive device and on the other hand by the ink ribbon, both conical projections grind against one another. As a result, the drawn bobbin is braked and the unwinding ribbon is kept taut.

Zur Umkehrung der Transportrichtung des Farbbandes ist jedem Zahnrad auf der Schaltwelle ein Schalthebel zugeordnet, der durch das Farbband gegen die Stirnseite des zugeordneten Zahnrades verschwenkt wird, daß mindestens einem dieser Schalthebel ein entgegen einer Federkraft verschiebbarer Rollenhebel zugeordnet ist und daß im Wirkungsbereich dieses Rollenhebels die Abrollebene des Schalthebels einen dachförmigen Querschnitt besitzt. Beide Schalthebel sind zweckmäßig starr miteinander verbunden. Die Länge der Auflaufschräge der dachförmigen Abrollebene ist etwas kleiner als die Abstände zwischen den Schalthebeln und den zugeordneten Zahnrädern. Um diese Abstände definiert einzuhalten, sind die Schalthebel mit Ansätzen versehen. Kommt während einer Umschaltphase der Ansatz eines Schalthebels mit der Stirnseite des zugeordneten Zahnrades in Verbindung, so hat der Rollenhebel gerade die Spitze der dachförmigen Abrollebene überschritten und befindet sich am Beginn der Ablaufschräge der dachförmigen Abrollebene. Hierdurch kommt die Federkraft des Abrollhebels zur Wirkung und übt infolge des nun auftretenden Kräfteparallelogrammes eine Kraft in Richtung der Schaltwellenachse aus. Dadurch wird mit Beginn der Verschiebung der Schaltwelle die hierzu erforderliche Kraft voll von der Feder des Rollenhebels aufgebracht. Das Farbband wird zum eigentlichen Umkehrvorgang voll entlastet. Die von ihm aufzubringende Kraft bezieht sich lediglich auf das Verschwenken der beiden Schalthebel.To reverse the transport direction of the ribbon, a gear lever is assigned to each gear on the selector shaft, which is pivoted by the ribbon against the end face of the assigned gear, that at least one of these shift levers is assigned a roller lever that can be moved against a spring force, and that the rolling plane is in the area of action of this roller lever of the shift lever has a roof-shaped cross section. Both shift levers are expediently rigidly connected to one another. The length of the run-up slope of the roof-shaped rolling plane is somewhat smaller than the distances between the shift levers and the associated gear wheels. In order to maintain these distances in a defined manner, the shift levers are provided with lugs. If the approach of a shift lever comes into contact with the end face of the assigned gear during a changeover phase, the roller lever has just exceeded the tip of the roof-shaped rolling plane and is at the beginning of the slope of the roof-shaped rolling plane. As a result, the spring force of the rolling lever comes into effect and, due to the force parallelogram now occurring, exerts a force in the direction of the shift shaft axis. As a result, the force required for this is fully applied by the spring of the roller lever at the beginning of the shifting of the selector shaft. The ribbon is fully relieved for the actual reversal process. The force to be applied only relates to the pivoting of the two shift levers.

Die Erfindung wird anhand eines in den Zeichnungen dargestellten Ausführungsbeispieles näher erläutert. Es zeigen:

  • Fig. 1 die Draufsicht einer Druckeinrichtung gemäß der Erfindung teilweise im Schnitt,
  • Fig. 2 die gleiche Ansicht der Fig. 1, wobei nunmehr die Abschwenkvorrichtung deutlich dargestellt ist,
  • Fig. 3 eine Seitenansicht der Anordnung nach Fig. 1, bei der die Halbtourenkupplung dargestellt ist, und
  • Fig. 4. die Vorrichtung zur Umschaltung der Transportrichtung des Farbbandes.
The invention is explained in more detail using an exemplary embodiment shown in the drawings. Show it:
  • 1 is a plan view, partly in section, of a printing device according to the invention,
  • 2 shows the same view of FIG. 1, the pivoting device now being clearly shown,
  • Fig. 3 is a side view of the arrangement of FIG. 1, in which the half-speed clutch is shown, and
  • Fig. 4. the device for switching the transport direction of the ribbon.

Die in den Zeichnungen dargestellte Druckeinrichtung besteht aus den Gehäusewänden 36 und 361, die miteinander durch die Abstandsschienen 27 und 28 verbunden sind. In den Seitenwänden 36 und 361 sind das Druckwiderlager 53, die Gleitscheinen für den Transportwagen 56 des Druckkopfes 49 befestigt. In den Gehäusewänden 36 und 361 ist auch die Hohlwelle 10 befestigt, in der die Schaltwelle 8 drehbar und verschiebbar gelagert ist. An den über die Gehäusewände hinausragenden Enden der Schaltwelle 8 sind Zahnräder 7 und 9 fest angeordnet. Diese Zahnräder 7 und 9 kommen durch Verschieben der Schaltwelle 8 wechselweise mit ihnen zugeordneten Zahnkränzen 141 und 131 in Eingriff. Diese Zahnkränze sind Teil zugeordneter Spulenträger 13 und 14, auf deren Dorne 16 und 29 die Farbbandspulen 11 und 12 aufgesteckt werden. Die meist aus Blech bestehenden Farbbandspulen 11 und 12 werden durch Dauermagnete 15 (nur auf einer Seite dargestellt) gehalten. Das Farbband 17 wird über hintere Umlenkrollen 55 und 551 sowie über vordere Umlenkrollen 54 und 541 an der Stirnseite des Druckkopfes 49 vorbeigeführt. Alle Umlenkrollen sind dabei auf dem abziehbaren Druckkopf gelagert.The printing device shown in the drawings consists of the housing walls 36 and 361, which are connected to one another by the spacer rails 27 and 28. In the side walls 36 and 361, the pressure abutment 53 and the sliding blocks for the transport carriage 56 of the print head 49 are fastened. In the housing walls 36 and 361, the hollow shaft 10 is also fixed, in which the control shaft 8 is rotatably and slidably mounted. Gears 7 and 9 are fixedly arranged on the ends of the selector shaft 8 projecting beyond the housing walls. These gear wheels 7 and 9 alternately engage with gear rings 141 and 131 assigned to them by shifting the selector shaft 8. These sprockets are part of assigned spool supports 13 and 14, on the mandrels 16 and 29 of which the ribbon spools 11 and 12 are attached. The ribbon spools 11 and 12, which mostly consist of sheet metal, are held by permanent magnets 15 (shown only on one side). The ink ribbon 17 is guided over the rear deflection rollers 55 and 551 and over the front deflection rollers 54 and 541 on the front side of the print head 49. All pulleys are stored on the removable print head.

Beide Zahnräder 7 und 9 sowie beide Spulenträger 13 und 14 besitzen kegelförmige Ansätze 71, 91 bzw. 132 und 142, deren Kegelflächen zueinander gerichtet sind. Die Kegelflächen 71 und 142 des Zahnrades 7 und des zugeordneten Zahnkranzes 141 kommen miteinander in Berührung, wenn Zahnrad und Zahnkranz nach dem Umschaltvorgang außer' Eingriff sind. Bei der in Fig. 1 dargestellten Lage der Schaltwelle 8 befinden sich Zahnrad 9 und Zahnkranz 131 miteinander in Eingriff, und die Kegelflächen 91 und 132 sind nicht miteinander in Berührung. Das Zahnrad 7 und der Zahnkranz 141 sind dagegen außer Eingriff, während die Kegelflächen 71 und 142 sich berühren. Wird die Schaltwelle 8 über das Zahnrad 7 angetrieben, so wird über das Zahnrad 9 der Spulenträger 13 und damit die Farbbandspule 11 angetrieben. Das Farbband 17 wird dadurch von der Farbbandspule 12 auf die Farbbandspule 11 umgespult. Das Zahnrad 7 und der Spulenträger 14 machen dabei gegenläufige Drehbewegungen, so daß die Oberflächen der Kegel 71 und 142 aufeinander reiben. Durch diese Reibungskraft wird auf die Farbbandspule 12 entgegen der Abwickelrichtung eine Kraft ausgeübt, die eine stetige Straffung des Farbbandes 17 bewirkt. Nach Umschalten der Schaltwelle 8 wird diese Straffung durch die Reibungskräfte zwischen den Kegelrädern 91 und 132 erzielt. Die Verschiebung der Schaltwelle 8 und damit die Umschaltung der Transportrichtung des Farbbandes 17 wird weiter unten anhand der Fig. 4 näher beschrieben.Both gear wheels 7 and 9 and both coil carriers 13 and 14 have conical projections 71, 91 or 132 and 142, the conical surfaces of which are directed towards one another. The tapered surfaces 71 and 142 of the gear 7 and the associated ring gear 141 come into contact with each other when the gear and ring gear are out of engagement after the switching process. In the position of the selector shaft 8 shown in FIG. 1, the gear 9 and ring gear 131 are in engagement with one another, and the conical surfaces 91 and 132 are not in contact with one another. The gear 7 and the ring gear 141 are disengaged, while the conical surfaces 71 and 142 touch. If the control shaft 8 is driven via the gear 7, the spool 13 and thus the ribbon reel 11 are driven via the gear 9. The ink ribbon 17 is thereby rewound from the ink ribbon spool 12 to the ink ribbon spool 11. The gear 7 and the coil carrier 14 make opposite rotational movements, so that the surfaces of the cones 71 and 142 rub against each other. This frictional force exerts a force on the ribbon spool 12 against the unwinding direction, which causes the ribbon 17 to be tightened continuously. After switching the selector shaft 8, this tightening is achieved by the frictional forces between the bevel gears 91 and 132. The shift of the control shaft 8 and thus the switching of the transport direction of the ink ribbon 17 is described in more detail below with reference to FIG. 4.

An der Gehäuseseitenwand 36 ist ein Winkelträger 35 befestigt, an dem ein aus den Zahnrädern 3, 4 und 5 bestehendes Getriebe gelagert ist. Dieses Getriebe wird über das Zahnrad 2 eines Elektromotors 1 angetrieben, der an der Gehäusewand 36 befestigt ist. Das Zahnrad 5 ist auf einer Antriebsachse 37 befestigt, die in der Gehäusewand 36 und dem Winkeiträger 35 gelagert ist. Diese Achse 37 ist die gemeinsame Antriebsachse für den Farbbandtransport und die Abschwenkung des Druckkopfes. Zum Antrieb des Farbbandtransportes und der Umschaltung der Schaltwelle 8 ist auf der Achse 37 ein Zahnrad 6 angeordnet, das über ein Richtgesperre 65 von der Welle 37 angetrieben wird und das ständig mit dem Zahnrad 7 in Wirkverbindung steht. Die Sperrichtung des Richtgesperres 65 ist so gewählt, daß bei Antreib der gemeinsamen Achse 37 durch den Elektromotor 1 in der einen Richtung die Antriebskraft auf das Zahnrad 7 übertragen wird, bei Drehrichtung der Achse 37 in entgegengesetzter Richtung dagegen nicht. Die in der Gehäusewand 36 im Lager 39 drehbar angeordnete Antriebsachse 37 ist über die Lagerstelle 38 in dem Winkelträger 35 hinaus verlängert und trägt auf dieser Verlängerung das Kurvenstück einer Halbtourenkupplung. Dieses Kurvenstück ist über ein Richtgesperre 44 auf dieser gemeinsamen Antriebsachse 37 gelagert, deren Sperrichtung der Sperrichtung des Richtgesperres 65 entgegengesetzt ist. Dies bedeutet: bei Sperrung des Richtgesperres 65 ist das Richtgesperre 44 nicht gesperrt. Ist dagegen das Richtgesperre 65 freilaufend, so sperrt das Richtgesperre 44 und überträgt damit die vom Elektromotor 1 ausgehende Antriebskraft auf die Halbtourenkupplung.On the housing side wall 36 is a Angle bracket 35 attached to which a gear consisting of the gears 3, 4 and 5 is mounted. This gear is driven by the gear 2 of an electric motor 1, which is attached to the housing wall 36. The gear wheel 5 is fastened on a drive shaft 37 which is mounted in the housing wall 36 and the angular support 35. This axis 37 is the common drive axis for the ribbon transport and the pivoting of the print head. To drive the ribbon transport and the switching of the selector shaft 8, a gear 6 is arranged on the axis 37, which is driven by a directional lock 65 from the shaft 37 and which is constantly in operative connection with the gear 7. The locking direction of the directional lock 65 is selected so that when the common axis 37 is driven by the electric motor 1 in one direction the driving force is transmitted to the gear 7, but not when the axis 37 is rotating in the opposite direction. The drive shaft 37, which is rotatably arranged in the housing wall 36 in the bearing 39, is extended beyond the bearing point 38 in the angle bracket 35 and bears the curved part of a half-speed clutch on this extension. This curve piece is mounted on a directional lock 44 on this common drive shaft 37, the locking direction of which is opposite to the locking direction of the locking mechanism 65. This means that when the directional lock 65 is locked, the directional lock 44 is not locked. If, however, the directional lock 65 is free-running, the directional lock 44 locks and thus transmits the driving force emanating from the electric motor 1 to the half-speed clutch.

Die Halbtourenkupplung besitzt zwei Kurvenscheiben 40 und 59. Mit beiden Kurvenscheiben werden zwei Hebel 43 und 58 gesteuert, die auf einer gemeinsamen Drehachse 57 gelagert sind. Der Hebel 43 ist an seinem einen Ende über eine Feder 66 mit der Gehäusewand 36 verbunden und greift infolge dieser Federkraft mit seiner Abstützrolle 61 in Ausnehmungen der Kurvenscheibe 59 ein. Diese Ausnehmungen liegen annähernd diametral gegenüber und bewirken eine Arrtetierung der Halbtourenkupplung in den beiden Endlagen des Abschwenkhebels 58, der mit seiner Abstützrolle auf der Kurvenscheibe 40 um den Drehpunkt 57 hin- und hergeschwenkt wird. Dieser Abschwenkhebel 58 besitzt einen Ansatz 52, an dem das Zugseil 46 mit seinem einen Ende befestigt ist. Über eine Umlenkrolle 51 wird das Seil zum Druckkopf 49 umgelenkt und auf der anderen Seite der Druckeinrichtung an einer Blattfeder 45 befestigt, die ihrerseits fest mit der Gehäusewand 361 verbunden ist. Mit Hilfe der Einstellschraube 63 können Längentoleranzen des Seiles 46 ausgeglichen werden. Im Bereich des Druckkopfes 49 wird das Seil 46 über drei Umlenkrollen 47, 48 und 50 gelenkt. Dabei sind die Rollen 47 und 48 auf dem Wagen 56 gelagert, während die Rolle 50 auf dem vorderen Teil des Druckkopfes 49 befestigt ist.The half-speed clutch has two cams 40 and 59. With both cams, two levers 43 and 58 are controlled, which are mounted on a common axis of rotation 57. The lever 43 is connected at one end to the housing wall 36 via a spring 66 and, as a result of this spring force, engages with its support roller 61 in recesses in the cam plate 59. These recesses are approximately diametrically opposite and cause the half-speed clutch to be locked in the two end positions of the pivoting lever 58, which is pivoted back and forth with the support roller on the cam disk 40 about the pivot point 57. This pivoting lever 58 has a shoulder 52 to which the pull cable 46 is fastened at one end. The cable is deflected to the print head 49 via a deflection roller 51 and fastened to a leaf spring 45 on the other side of the printing device, which in turn is firmly connected to the housing wall 361. With the aid of the adjusting screw 63, length tolerances of the rope 46 can be compensated for. In the area of the print head 49, the rope 46 is steered via three deflection rollers 47, 48 and 50. The rollers 47 and 48 are mounted on the carriage 56, while the roller 50 is attached to the front part of the print head 49.

Wird während einer Halbdrehung der Halbtourenkupplung die Kurvenscheibe 40 um eine halbe Drehung gedreht, so wird der Abschwenkhebel 58 mit seiner Abstützrolle 60 durch die exzentrisch gelagerte Kurvenscheibe 40 verschwenkt. Dadurch wird das Seil 46 gestrafft. Infolge dieser Straffung wird die Umlenkrolle 50 und damit der Druckkopf 49 in Pfeilrichtung vom Druckwiderlager 53 abgeschwenkt. In dieser abgeschwenkten Lage wird die Halbtourenkupplung stillgesetzt, indem der Nocken 62 den Mikroschalter 41 betätigt. Durch den Mikroschalter 41 wird der Elektromotor 1 abgeschaltet und damit auch der Antrieb für die gemeinsame Antriebsachse 37. Eine Verschiebung der Halbtourenkupplung wird durch die Abstützrolle 61 des Fixierhebels 43 verhindert. Sobald der Druckkopf 49 in Pfeilrichtung auf das Druckwiderlager 53 hin bewegt werden soll, wird der Elektromotor 1 erneut erregt und die Halbtourenkupplung über das Richtgesperre 44 um eine weitere halbe Umdrehung weitergedreht. Sobald der Nocken 62 die in Fig. 3 gezeigte Stellung wieder erreicht hat, wird der Mikroschalter 42 betätigt, der nunmehr eine Reversierung des Elektromotors einleitet. Während dieser halben Umdrehung der Halbtourenkupplung wird der Schwenkhebel 58 wieder seine in Fig. 3 gezeigte Lage einnehmen und das Seil 46 lockern. Infolge einer nicht dargestellten Federkraft wird der Druckkopf 49 in Richtung auf das Druckwiderlager 53 bewegt.If the cam disk 40 is rotated by half a turn during a half turn of the half-speed clutch, then the pivoting lever 58 with its support roller 60 is pivoted by the eccentrically mounted cam disk 40. As a result, the rope 46 is tightened. As a result of this tightening, the deflection roller 50 and thus the print head 49 are pivoted away from the pressure abutment 53 in the direction of the arrow. In this pivoted-down position, the half-speed clutch is stopped by the cam 62 actuating the microswitch 41. The electric motor 1 is switched off by the microswitch 41 and thus also the drive for the common drive axle 37. A displacement of the half-speed clutch is prevented by the support roller 61 of the fixing lever 43. As soon as the print head 49 is to be moved in the direction of the arrow toward the pressure abutment 53, the electric motor 1 is excited again and the half-speed clutch is rotated a further half turn via the directional lock 44. As soon as the cam 62 has reached the position shown in FIG. 3 again, the microswitch 42 is actuated, which now initiates a reversal of the electric motor. During this half revolution of the half-speed clutch, the pivot lever 58 will again assume its position shown in FIG. 3 and loosen the cable 46. Due to a spring force, not shown, the print head 49 is moved in the direction of the platen 53.

Nach Reversierung des Elektromotors 1 wird nunmehr durch Richtungsumkehr der Antreibsachse 37 das Richtgesperre 65 wirksam und damit auch der Farbbandtransport bzw. bedarfsweise die Farbbandumschaltung.After reversing the electric motor 1, the directional ratchet 65 now becomes effective by reversing the direction of the drive axis 37 and thus also the ribbon transport or, if necessary, the ribbon switch.

Das Farbband 17 besitzt, wie in Fig. 4 gezeigt, an seinen beiden Enden Hemmösen 18, durch die ein Verschwenken der jeweils zugeordneten Schalthebel 19 und 20 erfolgt.The ribbon 17 has, as shown in Fig. 4, at both ends of the eyelets 18 through which the respective associated shift levers 19 and 20 are pivoted.

Die Schalthebel 19 und 20 sind in Lagern 21 und 22 an den Gehäusewänden 36 und 361 schwenkbar gelagert. An ihren einen Enden sind sie durch eine Verbindungsstange 23 starr miteinander gekoppelt. D. h. sie führen stets die gleichen Bewegungen aus. An ihren anderen Enden sind die Schalthebel 19 und 20 mit gabelförmigen Ansätzen 30 und 31 versehen, durch die das Farbband 17 gleitet.The shift levers 19 and 20 are pivotally mounted in bearings 21 and 22 on the housing walls 36 and 361. At one end they are rigidly coupled to one another by a connecting rod 23. I.e. they always make the same movements. At their other ends, the shift levers 19 and 20 are provided with fork-shaped projections 30 and 31 through which the ribbon 17 slides.

Im Bereich des einen Hebels 19 ist an der Gehäusewand 36 zusätzlich ein Rollenhebel verschiebbar angeordnet. Die Verschiebung des Rollenhebels ist senkrecht zur Schaltwelle 8 innerhalb der Zeichenebene gerichtet. In seiner gezeichneten Ruhestellung wird der Rollenhebel 24 durch die Kraft einer Zugfeder 25 gehalten. Im Wirkungsbereich des Rollenhebels 24 ist die Seitenkante des Hebels 19 dachförmig ausgebildet. Die Abrollebene 34 für den Rollenhebel 24 besteht somit aus einer Auflaufschräge 341 und einer Ablaufschräge 342. Der Schalthebel 20 ist in dem vorliegenden Ausführungsbeispiel ebenfalls mit diesen Schrägen ausgebildet. Dies erfolgt lediglich aus Herstellungsgründen, da auf diese Weise beide Schalthebel 19 und 20 gleiche Stanzteile sind. Weiterhin besitzen die Schalthebel 19 und 20 Ansätze 26 und 33, die in Wirkstellung der Schalthebel 19 und 20 auf den Zahnrädern 7 und 9 aufliegen und in Ruhestellung der Schalthebel von diesen abgehoben sind. Die in Fig. 4 rechts dargestellte Lage des Schalthebels 20 stellt also die Wirkstellung dar, während die in Fig. 4 links dargestellte Lage des Schalthebels 19 die Ruhestellung ist.In the area of the one lever 19, a roller lever is additionally arranged displaceably on the housing wall 36. The displacement of the roller lever is directed perpendicular to the control shaft 8 within the plane of the drawing. In its drawn rest position, the roller lever 24 is held by the force of a tension spring 25. In the effective range of the roller lever 24, the side edge of the lever 19 is roof-shaped. The rolling plane 34 for the roller lever 24 thus consists of one Run-up slope 341 and a run-off slope 342. The shift lever 20 is also formed with these slopes in the present exemplary embodiment. This is only for manufacturing reasons, since in this way both shift levers 19 and 20 are the same stamped parts. Furthermore, the shift levers 19 and 20 have lugs 26 and 33, which rest in the operative position of the shift levers 19 and 20 on the gears 7 and 9 and are lifted from the latter in the rest position. The position of the shift lever 20 shown on the right in FIG. 4 thus represents the active position, while the position of the shift lever 19 shown on the left in FIG. 4 is the rest position.

Wird das Farbband 17 in Pfeilrichtung bewegt und ist es von der Vorratsspule abgespult, so schlägt die Hemmöse 18 gegen den Ansatz 31 des Schalthebels 19 und nimmt diesen in Pfeilrichtung mit. Dadurch wird der Rollenhebel 24 entgegen der Kraft der Feder 25 nach oben verschoben, bis der Rollenhebel die obere Spitze der dachförmigen Abrollebene 34 überschritten hat. In diesem Zeitpunkt kommt der Ansatz 33 nach Zurücklegen des Weges 32 auf das Zahnrad 7 zu liegen. Gleichzeitig kommt infolge der von der Feder 25 über den Rollenhebel 24 auf die Ablaufschräge ausgeübte Kraft zur Wirkung. Durch das dabei auftretende Kräfteparallelogramm wird von dem Ansatz 33 auf das Zahnrad 7 eine Kraft ausgeübt, die axial zur Schaltwelle 8 wirkt und diese verschiebt. Während der Bewegung des Schalthebels 19 bis zum Anschlag des Ansatzes 33 an das Zahnrad 7 ist über die Verbindungsstange 23 der Ansatz 26 des Schalthebels 20 von dem Zahnrad 9 abgehoben worden. Dadurch kann der axial wirkenden Kraft, die vom Schalthebel 19 auf die Schaltwelle 8 ausgeübt wird, kein Widerstand entgegengesetzt werden.If the ink ribbon 17 is moved in the direction of the arrow and it is unwound from the supply spool, the restraining eye 18 strikes the shoulder 31 of the shift lever 19 and takes it along in the direction of the arrow. As a result, the roller lever 24 is pushed upward against the force of the spring 25 until the roller lever has exceeded the upper tip of the roof-shaped rolling plane 34. At this time, the approach 33 comes to rest on the gear 7 after covering the path 32. At the same time, due to the force exerted by the spring 25 on the roller lever 24 on the run-off slope, it acts. As a result of the parallelogram of forces occurring, a force is exerted on the gear 7 by the attachment 33, which acts axially to the shift shaft 8 and shifts it. During the movement of the shift lever 19 up to the stop of the shoulder 33 on the gear 7, the shoulder 26 of the shift lever 20 has been lifted off the gear 9 via the connecting rod 23. As a result, the axially acting force exerted by the shift lever 19 on the shift shaft 8 cannot be resisted.

Nach der Verschiebung der Schaltwelle 8 ist nunmehr das Zahnrad 7 in Eingriff mit dem Zahnkranz 141. Dadurch wird das Farbband 17 entgegen der Pfeilrichtung bewegt. Der Schalthebel 19 bleibt weiterhin in seiner Arbeitsstellung, in der sich der Rollenhebel 24 auf der Ablaufschräge 342 der Abrollebene 34 befindet. Ist das Farbband 17 entgegen der Pfeilrichtung abgespult, so erscheint die am rechten Ende des Farbbandes befindliche, in Fig. 1 dargestellte Hemmöse im Bereich der Gabel 30 des Hebels 20. Dadurch wird in der vorher beschriebenen Weise nunmehr der Hebel 20 verschwenkt, bis der Ansatz 26 auf dem Zahnrad 9 anliegt. Dadurch ist um den gleichen Betrag auch der Schalthebel 19 verschwenkt worden und der Rollenhebel 24 entgegen der Kraft der Feder 25 über die Spitze der dachförmigen Abrollebene 34 angehoben worden. Danach wirkt wiederum die Federkraft der Feder 25 auf den Hebel 19 und über die Verbindungsstange 23 auf den Schalthebel 20, der nunmehr die Schaltwelle 8 nach links verschiebt. Dies bedeutet, daß die Auflaufschräge 341 von der Dachspitze aus gesehen etwas kleiner sein muß als der Abstand 32 zwischen dem Ansatz 33 des Schalthebels 19 und dem Zahnrad 7 und daß die Länge der Ablaufschräge 342 von der Dachspitze aus gesehen etwas kleiner sein muß als der Abstand des Ansatzes 26 des Schalthebels 20 zum Zahnrad 9. Dabei ist unter Länge der Abstand von der Dachspitze der Abrollebene 34 zum Auflagepunkt des Rollenhebels 23 in den beiden Stellungen zu verstehen.After the shifting of the selector shaft 8, the toothed wheel 7 is now in engagement with the toothed ring 141. The ink ribbon 17 is thereby moved in the opposite direction of the arrow. The shift lever 19 remains in its working position, in which the roller lever 24 is located on the run-off slope 342 of the rolling plane 34. If the ink ribbon 17 is unwound in the opposite direction of the arrow, the locking eyelet located at the right end of the ink ribbon, shown in FIG. 1, appears in the region of the fork 30 of the lever 20. As a result, the lever 20 is now pivoted in the manner previously described until the shoulder 26 rests on the gear 9. As a result, the shift lever 19 has also been pivoted by the same amount and the roller lever 24 has been raised against the force of the spring 25 over the top of the roof-shaped rolling plane 34. Then again the spring force of the spring 25 acts on the lever 19 and via the connecting rod 23 on the shift lever 20, which now shifts the shift shaft 8 to the left. This means that the ramp slope 341 seen from the roof top must be slightly smaller than the distance 32 between the shoulder 33 of the shift lever 19 and the gear 7 and that the length of the ramp slope 342 seen from the roof tip must be somewhat smaller than the distance of the extension 26 of the shift lever 20 to the gear wheel 9. Here, the distance from the roof top of the rolling plane 34 to the support point of the roller lever 23 is to be understood in the two positions.

Die Verschiebung der Welle 8 und der beiden Zahnräder 7 und 9 wird begrenzt jeweils durch den Anschlag des kegelförmigen Ansatzes 71 bzw. 91 an den kegelförmigen Anzatz 132 bzw. 142 der Spulenträger 13 bzw. 14. Werden die Auflaufschräge 341 und Abiaufschrage 342 in ihrer Steigung über das Maß hinaus weitergeführt, das lediglich zur Umschaltung erforderlich wäre, so werden durch die Feder 25 Kräfte auf die Schaltwelle 8 übertragen, die die Reibungskräfte zwischen den kegelförmigen Ansätzen der Zahnräder 7 und 9 mit den kegelförmigen Ansätzen der Spulenträger 13 und 14 verstärken. Dadurch werden die Reibungskräfte auch bei Verschleiß konstant gehalten.The displacement of the shaft 8 and the two gear wheels 7 and 9 is limited in each case by the abutment of the conical projection 71 or 91 on the conical projection 132 or 142 of the coil carriers 13 or 14 Continued beyond the extent that would only be required for switching, 25 forces are transmitted to the selector shaft 8 by the spring, which reinforce the frictional forces between the conical approaches of the gears 7 and 9 with the conical approaches of the coil carriers 13 and 14. This keeps the frictional forces constant even when worn.

Claims (6)

1. A device for transporting and reversing the transport direction of an ink ribbon, as desired, and for withdrawing the printing head from the platen in printing devices of a typewriter or accounting machine, in which the ribbon is reversed and transported by means of gearwheels which are rigidly connected to each other via a control shaft, said gearwheels alternately engaging, by the sliding of the control shaft in the longitudinal direction, associated gear rings of the reel holders arranged on the side of the printing device, the withdrawal of the printing head being effected by the tensioning of a cord which is secured at one end to the printing device and at the other end to a deflection lever and which is guided along the printing head via guide rollers, characterized in that one of the gearwheels (7) cooperating with the gear rings (141) on the reel holders (14) is permanently coupled, via a pawl-and-ratchet device (65), to a common drive shaft (3), the deflection lever (58) whose free end holds the cord (46) rolling down on an eccentric cam disc (40) of a cam mechanism which is connected to the common drive shaft (37) via a further pawl-and-ratchet device (44), the two pawl-and-ratchet devices (44, 65) being arranged to block in opposite directions and the common drive shaft (37) being drivable in a reversible manner by means of a single electric motor (1 ).
2. A device as claimed in Claim 1, characterized in that the cam mechanism comprises a second cam disc (59), which is provided with two recesses which are arranged in approximately diametrically opposite positions and in which a locking lever (43) can engage in order to lock the deflection lever (58) in one or the other of two extreme positions.
3. A device as claimed in the Claims 1 and 2, characterized in that the electric motor (1) is reversible.
4. A device as claimed in Claim 1; characterized in that the interconnected gearwheels (7, 9) and the reel holders (13, 14) associated therewith comprise conical parts (71, 91 and 132, 142) whose conical faces face each other and slide on each other in opposed directions for as long as the gearwheels (7, 9) and the associated gear ring (131, 141) do not mesh with each other.
5. A device as claimed in one or more of the Claims 1 to 4, characterized in that for the reversal of the transport direction of the ribbon each gearwheel (7, 9) on the control shaft has associated with it a control lever (19, 20) which is deflectible, by the ribbon (17), against the face of the associated gearwheel (7, 9), at least one of these control levers (19) having associated with it a roller lever (24) which is slidable against the force of a spring and which acts on a roof-shaped rolling face (34) of the control lever (19).
6. A device as claimed in Claim 5, characterized in that the control levers (19, 20) comprise projections (26, 33) which bear on the gearwheels (7, 9) in the operating position of the control levers (19, 20) and which are lifted off these gearwheels in the rest position of the control levers (19,20).
EP78200075A 1977-07-13 1978-07-03 Drive mechanism for printers, either for progressing or reversing an ink ribbon, or for retracting the printing head Expired EP0000413B1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE19772731593 DE2731593C3 (en) 1977-07-13 1977-07-13 Device for reversing the direction of movement of a ribbon in typewriters and accounting machines
DE2731593 1977-07-13
DE2731607 1977-07-13
DE19772731607 DE2731607C3 (en) 1977-07-13 1977-07-13 Drive device for transporting or reversing the transport direction of an ink ribbon as required and for pivoting the print head in printing devices

Publications (2)

Publication Number Publication Date
EP0000413A1 EP0000413A1 (en) 1979-01-24
EP0000413B1 true EP0000413B1 (en) 1980-12-10

Family

ID=25772317

Family Applications (1)

Application Number Title Priority Date Filing Date
EP78200075A Expired EP0000413B1 (en) 1977-07-13 1978-07-03 Drive mechanism for printers, either for progressing or reversing an ink ribbon, or for retracting the printing head

Country Status (5)

Country Link
US (1) US4265551A (en)
EP (1) EP0000413B1 (en)
JP (1) JPS5419813A (en)
DE (1) DE2860289D1 (en)
IT (1) IT1098666B (en)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3014822C2 (en) * 1980-04-15 1985-08-14 Mannesmann AG, 4000 Düsseldorf Drive device for a printer, in particular a matrix printer
DE3112079C2 (en) * 1981-03-27 1983-02-03 Triumph-Adler Aktiengesellschaft für Büro- und Informationstechnik, 8500 Nürnberg Device for lifting the printhead from the platen
US4658270A (en) * 1983-07-27 1987-04-14 Sharp Kabushiki Kaisha Recording apparatus
JPS6178656A (en) * 1984-09-26 1986-04-22 Canon Inc Printing apparatus
US4974977A (en) * 1989-01-19 1990-12-04 Banctec, Inc. Print ribbon cartridge with vacuum buffer chambers
US6521211B1 (en) 1995-06-07 2003-02-18 Bristol-Myers Squibb Medical Imaging, Inc. Methods of imaging and treatment with targeted compositions
GB2383974B (en) * 2002-01-15 2006-01-18 Markem Tech Ltd Improvements in or relating to printing apparatus
US7790013B2 (en) * 2006-03-29 2010-09-07 Safe Hydrogen, Llc Storing and transporting energy
US20120027489A1 (en) * 2010-07-30 2012-02-02 Yaw Horng Yap Printer with coupled media feed and print head activation mechanism
SA112330278B1 (en) 2011-02-18 2015-10-09 ستيم سينتركس، انك. Novel modulators and methods of use
EP2691419B1 (en) 2011-03-31 2016-11-09 INSERM - Institut National de la Santé et de la Recherche Médicale Antibodies directed against icos and uses thereof

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK33257C (en) * 1923-05-07 1924-05-26 Christian Falck-Loendahl Procedure for Dry Preservation of Eggs.
GB674070A (en) * 1949-05-04 1952-06-18 British Vacuum Cleaner And Eng Improvements in ink ribbon progressing and reversing devices
US2654461A (en) * 1949-07-23 1953-10-06 Bovio Ilario Automatic ink-ribbon reversal mechanism for typewriters and printing business machines
DE1021412B (en) * 1955-12-06 1957-12-27 Siemens Ag Arrangement for controlling the movement of the ribbon fork in teletyping machines
US2998878A (en) * 1960-09-09 1961-09-05 Syracuse Stamping Company Inc Ribbon spool
US3038582A (en) * 1960-12-23 1962-06-12 Royal Mcbee Corp Ribbon feed mechanism for business machines and the like
US3461996A (en) * 1966-12-20 1969-08-19 Monroe Int Reed operated printer
US3587813A (en) * 1968-05-09 1971-06-28 Burroughs Corp Feed and reverse mechanism for an inking ribbon
DE2233169A1 (en) * 1972-07-06 1974-01-17 Triumph Werke Nuernberg Ag SWITCHING DEVICE FOR ROTATING TYPE CARRIERS OF TYPICAL OR SIMILAR MACHINES
NL153804B (en) * 1972-07-14 1977-07-15 Triumph Werke Nuernberg Ag PRESSURE DEVICE.
US3807544A (en) * 1972-07-24 1974-04-30 W Glover Universal ribbon spool having a magnetic adapter with a rupturable diaphragm
US3990563A (en) * 1974-06-20 1976-11-09 U.S. Philips Corporation Spool-ejecting ink ribbon device

Also Published As

Publication number Publication date
IT7825502A0 (en) 1978-07-10
EP0000413A1 (en) 1979-01-24
IT1098666B (en) 1985-09-07
US4265551A (en) 1981-05-05
JPS5419813A (en) 1979-02-14
DE2860289D1 (en) 1981-02-19

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