Single cycle printing machine

Description

[0001] This invention relates to printing machines for printing characters on a substrate and more particularly to such machines in which each printing cycle is initiated by an operator. Such machines are hereinafter referred to as "single cycle printing machines".

[0002] With single cycle printing machines and particularly those used for printing numbers in sequence on successive sheets such as coupons, lottery tickets or cheques, it is important that the printing cycle be inhibited if the substrate on which printing is to take place is absent from or displaced from a correct printing location. It is also important that these machines should be operable under manual control in the event of power failure.

[0003] In the prior art most single cycle machines employ one or more micro-switches to detect the presence or absence of the article to be printed, e.g. a coupon, cheque or lottery ticket. Insertion of the article actuates the micro-switches which complete an electrical circuit via a manual pushbutton or operating lever, which can then be depressed to operate a dog clutch which releases the drive of the printing mechanism. In the circuit completed by the depression of the pushbutton or actuation of the operating lever there is a relay which is closed to energise an electric motor, the latter driving the printing mechanism to perform the printing operation. As the cycle nears completion, the printing stroke is completed, the printed article is discharged and the dog clutch is re-engaged to lock the mechanism. Release of the printed article restores the micro-switches to their initial positions. The mechanism can now once again be operated when a further article is inserted and actuates the micro-switches and when subsequent actuation of the pushbutton or operating lever causes the cycle to be repeated.

[0004] The principal disadvantage of the prior art machine described is the complexity of the dog clutch mechanism employed. A typical form of such a mechanism involves, upon engagement of a pawl with the dog provided on a tubular member, the winding of a flat helical spring tightly into engagement with a bush to provide the driving connection between a member driven by the motor and the printing mechanism. A further disadvantage is that reliance for consistent operation is placed on one or more micro-switches for detecting the presence or absence of the article to be printed. One object of the present invention accordingly is to provide a single cycle printing machine in which simpler and, accordingly, less costly, mechanism is utilised. A further object is to provide a single cycle printing machine in which the detection of the presence or absence of the article to be printed is more reliably effected and this means without dependence upon micro-switch actuation.

[0005] US-A-3180574 describes a stamping machine prdvided with a mechanical locking device to prevent printing unless a document is present on the printing plate. The device comprises a feeler element which can engage in a slot in the printing plate in the absence of a document. The feeler is connected by an assembly of links co-operating with a cam integral with a hand crank. In the absence of a document, the feeler locates in the slot and the links move so as to lock the cam and prevent it from rotating. When a document is introduced, and the crank turned, the feeler abuts on the document and the link assembly is freed from the cam which turns and actuates the printing mechanism.

[0006] The present invention provides alternative means for sensing the presence or absence of a sheet to be printed which avoids use of the mechanism including the assembly of links and co-operating cam described above.

[0007] The present invention consists in a single cycle printing machine for printing characters on sheet material located on a printing platform of the machine, comprising rotary printing drive mechanism including a detent for locking the mechanism, release means operable to disengage the detent thereby to free the drive mechanism, and actuating means for operating the release means comprising mechanical sensing elements for sensing the presence or absence of sheet to be printed which, in the event of a sheet not being correctly located for printing, are disposed to inhibit actuation of the release means, whilst if sheet is correctly located for printing, the sensing elements are disposed to enable actuation of the release means thereby to allow initiation of a printing cycle, characterised in that the mechanical sensing elements of the actuating means include a bridge mounted on the printing platform and having a cross-piece and differentially spring-loaded support posts, the stronger spring-loaded post extending through an aperture in the printing platform below which it engages the release means which operate the detent and the weaker spring-loaded post being disposed over a further aperture in the printing platform over which in the correct printing position thereof, an edge of sheet to be printed is located to inhibit movement of the weaker spring-loaded post into the further aperture, whereby upon moving of the cross-piece against the spring-loading of the support posts, in the event of sheet not being correctly located for printing, the weaker spring-loaded post is allowed to pass into the further aperture and insufficient force is exerted at the stronger spring-loaded post to actuate the release means, whilst if sheet is correctly located for printing, the resistance of the sheet to movement of the weaker spring-loaded post into the further aperture enables movement of the stronger spring-loaded post to actuate the release means thereby to allow initiation of a printing cycle.

[0008] The release means, advantageously, comprise a pivoted lever one end of which is engaged by the stronger spring-loaded post and rotation of which by movement of said post displaces a spring-loaded rod of the detent to free the printing drive mechanism.

[0009] Preferably, there is provided a pivotally supported arm which engages the cross-piece of the bridge and pivotal movement of this arm moves the cross-piece against the bias of the spring-loaded bridge posts and is under the control of a movable element which is operator actuated.

[0010] Advantageously, the printing drive mechanism comprises a driven pulley which completes one revolution for each printing cycle and the spring-biased rod of the detent is urged towards the rotational axis of the pulley the detent further including an arm (pivotally mounted) on the pulley which projects beyond the periphery of the pulley where it is engaged by the rod to lock the pulley and prevent rotation thereof, movement of the rod against the biasing spring thereof freeing the pulley for rotation. Preferably the arm extends and is pivotal within a radially extending slot in the pulley against the action of a biasing spring so that towards completion of a revolution of the driven pulley, the arm engages the rod and the biasing spring of the arm is stressed to cushion the final part of the movement of the driven pulley.

[0011] Suitably, the driven pulley is formed in a face thereof with a cam track engaged by a cam follower the latter being reciprocated during rotation of the pulley to drive the printing mechanism counter and ribbon feed. The pulley is also preferably formed with peripheral gear teeth which engage a gear which drives printing mechanism for effecting printing on the sheet on the printing platform.

[0012] The invention will now be described, by way of example, with reference to the accompanying drawings, in which:-

Figure 1, is a side elevation of a single cycle printing machine according to the invention,

Figure 2, is a side elevation of the machine of Figure 1 seen from a somewhat different angle and with the mechanism in a different position,

Figure 3, is an end elevation of a driven pulley of the operating mechanism of the machine of Figures 1 and 2,

Figure 4, is a side elevation of the pulley of Figure 3 with a part removed to show interior construction,

Figure 5, is a sectional side elevation of Figure 3, and

Figure 6, is a side elevation of the pulley of Figure 3 as seen looking from the left of that Figure.

[0013] Referring to the drawings, a single-cycle printing machine 1 is employed for printing successive machine readable members on sheets such as cheques, coupons, lottery tickets etc. and includes a driven pulley 3 formed with a central peripheral groove 5 through which the pulley is driven from an electric motor which drives by way of a reduction gear box a drive pulley which is engaged by an endless belt of circular cross-section which co-operates with the drive pulley and with the groove 5 of the driven pulley 3. A handle is provided which in the event of power failure is fitted to the shaft of the drive pulley so that the latter can be manually rotated to turn the driven pulley and this operates the printing mechanism which itself forms no part of the invention and is therefore not further described.

[0014] To lock the printing drive mechanism of the machine so as to prevent more than a single printing cycle taking place, there is provided a detent generally indicated at 7 having respective elements mounted on the driven pulley 3 and on the frame 10 of the machine. The detent element on the drive pulley comprises an arm 11 which extends in a radially extending slot 13 in the pulley the slot being sector shaped. The arm 11 is pivotally supported at its inner end at a location 15 which is spaced from the axis of rotation of the driven pulley. The sector shaped slot 13 intersects an arcuate slot 17 which contains ball bearings 19 forced apart by a helical spring 21 so that one of the ball bearings engages the arm 11 whilst the other engages the end of the arcuate slot 17 remote from the arm.

[0015] The slot 13 opens to the exterior of the driven pulley and the free end of the arm 11 projects a short distance radially beyond the open end of the slot where it is engaged by the detent element mounted on the frame 10. This latter element comprises a rod 23 which extends through coaxial holes in fixed abutments 25 provided on the frame 10. Between a fixed abutment 27 provided on the rod 23 and the abutment 25 remote from the driven pulley is provided a biasing spring 29 which biases the rod 23 towards the axis of rotation of the driven pulley 3. The inner end of the rod 23 lies in the rotational path of the outermost end of the arm 11 so that, as the driven pulley completes a rotation, the end of the arm 11 is engaged by the inner end of the rod 23. As the driven pulley 3 completes a rotation the arm 11 causes the spring 21 to be compressed, thus cushioning the final part of the rotational movement of the driven pulley 3.

[0016] The arcuate slot 17 in the driven pulley 3 is closed by means of a gear 31 which is secured by screws to the pulley and is of the same overall diameter as the pulley. The gear 31 engages with a gear 33 which is one third of the diameter of the gear 31. The drive pulley is also one third of the diameter of the driven pulley 3 so that, as the gear 33 drives the printing mechanism of the machine, that mechanism performs a single cycle of operation for one complete revolution of the pulley 3.

[0017] At the side of the pulley 3 remote from the gear 31 is formed a cam track 35 which is engaged by a cam follower connected with linkage mechanism which is reciprocally moved by the cam follower to effect indexing of the ink tape and operation of the number wheels of the counter mechanism forming the print box of the machine.

[0018] For disengaging the elements of the detent there are provided release means in the form of a lever 37 which is pivotally mounted on the frame 10 of the machine and which, at an end 38 thereof, engages the abutment 27 secured to the rod 23 on the side of the abutment remote from the biasing spring 29. Thus, rotation of the lever 37 to move the rod 23 against the action of the biasing spring 29 effects removal of the inner end of the rod 23 from the path of movement of the free end of the arm 11, thus freeing the driven pulley 3 to rotate the printing mechanism of the machine.

[0019] The end 39 of the lever 37 remote from the end 38 thereof is engaged by actuating means (generally indicated at 41) which include sensing mechanism (generally indicated at 43) for sensing the presence or absence of a sheet, such as a coupon, to be printed on a printing platform 45 of the machine.

[0020] The actuating means comprise a bridge 47 which straddles the printing platform 45 of the machine and comprises upright posts 49 and 51 on upper ends of which is engaged a cross-piece 53, the upper ends of the posts passing through slots in the cross-piece 53. The post 49 extends through an aperture in the platform 45 and through coaxial bearings 55 and 57 respectively provided in the platform 45 and a bracket 59 secured to the platform 45. An abutment 61 is secured to the post 49 between which and the bearing 55 is disposed a relatively strong helical biasing spring 63 which urges the post 49 in a direction away from the end 39 of the lever 37. When the spring 63 is unstressed the post 49 at the lower end thereof engages the end 39 of the lever 37.

[0021] The post 51 of the bridge 47 passes through an aperture in an abutment 65 secured to the frame 10 of the machine. Between the abutment 65 and an abutment 67 fixed to the post 51 is a relatively weak helical biasing spring 69 which biases the post 51 in a direction away from the platform 45. In the unstressed position of the spring 69, the post 49 is disposed a short distance from the platform 45. The post 51 is also disposed in alignment with a small aperture (not shown) in the platform 45.

[0022] Engaging the cross-piece 53 is an arm 71 which at the end thereof remote from the cross-piece 53 is keyed to a rotatable shaft 73. Secured to the shaft 73 at the exterior of the machine is a lever (not shown) by means of which the shaft 73 can be rotated to cause the arm 71 to urge the cross-piece 53 in a direction against the action of the biasing springs 63 and 69.

[0023] When the shaft 73 is so rotated in the absence of a sheet to be printed such as a coupon correctly located on the platform 45, the cross-piece 53 is moved by the arm 71 against the biasing action of the springs 63 and 69. However, as the spring 69 is weaker than the spring 63, the post 51 is moved longitudinally against the action of the spring 69 and the end of the post remote from the cross-piece 53 passes through the aperture coaxial therewith in the printing platform 45. Accordingly, no longitudinal movement of the post 49 takes place and therefore the lever 37 is not rotated and the rod 23 remains in engagement with the free end of the arm 11 so that the driven pulley 3 is not freed.

[0024] When the shaft 73 is rotated in the presence of a sheet to be printed such as a coupon, an edge the latter covering the hole in the printing platform 45 coaxial with the post 51, the arm 71 moves the cross-piece 53 against the action of the biasing springs 63 and 69. As the biasing spring 69 is weaker than the spring 63, the post 51 is brought into engagement with the coupon, which provides resistance to movement of the post 51 additional to that of the spring 69. The combined resistance to movement of the post 51 afforded by the coupon and the spring 69 is sufficient to prevent further compression of the spring 69, with the result that the resistance of the spring 63 is overcome and the post 49 is moved axially, thus rotating the lever 37 so that the rod 23 is moved out of engagement with the arm 11, thus freeing the driven pulley 3. Immediately after the driven pulley 3 is freed for rotation, further axial movement of the post 49 actuates a micro-switch 75 in the energising circuit of the electric motor, which circuit includes a relay which holds the circuit energised after return movement of the post 49.

[0025] The hole in the printing platform 45 which is coaxial with the post 51 is so located that when a coupon is correctly located on the platform 45 for printing, the hole is covered by an extreme corner portion of the coupon. This ensures that the coupon is fully inserted on to the printing platform before printing can occur.

[0026] As the driven pulley 3 is rotated by the electric motor subsequent to disengagement of the detent formed by the arm 11 and rod 23, the printing cycle proceeds and, durinq printing, the cam follower is engaged in that part of the cam track 35 which is circular with respect to the rotational axis of the driven pulley 3. After the printing stroke is completed, the cam follower moves relatively to the lobe of the cam track 35, thus reciprocating the mechanism connected with the cam follower which indexes the printing ribbon and also the number wheels of the print box.

[0027] In a latter part of a revolution of the driven pulley 3, a notch 77 in the periphery of the pulley is engaged by a micro-switch (not shown) which operates a circuit which de-energises the electric motor. As the pulley 3 completes its revolution, the arm 11 is engaged by the rod 23 so that the final part of the rotation of the pulley 3 is cushioned as the helical spring 21 is compressed. The machine is now ready to perform a further printing cycle.

[0028] The endless belt which engages the motor pulley and the groove 5 of the driven pulley 3 is of circular cross-section as this facilitates slip of the belt relative to the groove 5 in the event that the motor continues to drive after the detent has arrested the pulley 3.

Claims

1. A single-cycle printing machine for printing characters on sheet material located on a printing platform (45) of the machine, comprising rotary printing drive mechanism including a detent (7) for locking the mechanism, release means operable to disengage the detent thereby to free the drive mechanism, and actuating means (41) for operating the release means comprising mechanical sensing elements (43) for sensing the presence or absence of sheet to be printed which, in the event of a sheet not being correctly located for printing, are disposed to inhibit actuation of the release means, whilst if sheet is correctly located for printing, the sensing elements are disposed to enable actuation of the release means thereby to allow initiation of a printing cycle, characterised in that the mechanical sensing elements of the actuating means include a bridge (47) mounted on the printing platform and having a cross-piece (53) and differentially spring-loaded support posts (49, 51), the stronger spring-loaded post (49) extending through an aperture in the printing platform below which it engages the release means which operate the detent and the weaker spring-loaded post (51) being disposed over a further aperture in the printing platform over which in the correct printing position thereof, an edge of sheet to be printed is located to inhibit movement of the weaker spring-loaded post into the further aperture, whereby upon moving of the cross-piece against the spring-loading of the support posts, in the event of sheet not being correctly located for printing, the weaker spring-loaded post is allowed to pass into the further aperture and insufficient force is exerted at the stronger spring-loaded post to actuate the release means, whilst if sheet is correctly located for printing, the resistance of the sheet to movement of the weaker spring-loaded post into the further aperture enables movement of the strong spring-loaded post to actuate the release means thereby to allow initiation of a printing cycle.

2. A machine as claimed in claim 1, characterised in that the release means comprise a pivoted lever (37), one end of which is engaged by the stronger spring-loaded post and rotation of the lever by movement of said post displaces a spring-loaded rod of the detent to free the printing drive mechanism.

3. A machine as claimed in claim 1 or claim 2, characterised in that there is provided a pivotally supported arm (71) which engages the cross-piece of the bridge and pivotal movement of this arm moves the cross-piece against the bias of the spring-loaded bridge posts and is under the control of a movable element which is operator actuated.

4. A machine as claimed in any preceding claim, characterised in that the printing drive mechanism comprises a driven pulley (3) which completes one revolution for each printing cycle and the spring-biased rod of the detent is urged towards the rotational axis of the pulley, the detent further including an arm (11) pivotally mounted on the pulley which projects beyond the periphery of the pulley where it is engaged by the rod to lock the pulley and prevent rotation thereof, movement of the rod against the biasing spring thereof freeing the pulley for rotation.

5. A machine as claimed in claim 4, characterised in that the arm extends and is pivotal within a radially extending slot (13) in the pulley against the action of a biasing spring (21) so that towards completion of a revolution of the driven pulley, the arm engages the rod and the biasing spring of the arm is stressed to cushion the final part of the movement of the driven pulley.

6. A machine as claimed in claim 4 or claim 5, characterised in that the driven pulley is formed in a face thereof with a cam track (35) engaged by a cam follower, the latter being reciprocated during rotation of the pulley to drive the printing mechanism counter and ribbon feed.

7. A machine as claimed in claim 6, characterised in that the pulley is formed with peripheral gear teeth which engage a gear (33) which drives printing mechanism for effecting printing on the sheet on the printing platform.

Revendications

1. Machine à imprimer mono-tour pour l'impression de caractères sur une feuille placée sur une plateforme d'impression (45) de la machine, comprenant un mécanisme rotatif d'entraînement d'impression qui comporte un encliquetage (7) pour bloquer le mécanisme, des moyens de libération qui peuvent être actionnés pour dégager l'encliquetage de manière à libérer le mécanisme d'entraînement, et des moyens de manoeuvre (41) pour actionner les moyens de libération, comprenant des éléments mécaniques de détection (43) pour détecter la présence ou l'absence d'une feuille à imprimer qui, dans le cas où une feuille n'est pas correctement placée pour l'impression, sont disposés de manière à empêcher la manoeuvre des moyens de libération, tandis que si la feuille est correctement placée pour l'impression, les éléments de détection sont disposés de manière à permettre la manoeuvre des moyens de libération, ce qui autorise le déclenchement d'un cycle d'impression, laquelle machine est caractérisée en ce que les éléments mécaniques de détection des moyens de manoeuvre comprennent un pont (47) monté sur la plateforme d'impression et comportant une traverse (53) et des montants de support (49, 51) chargés élastiquement de façon différente, le montant (49) le plus chargé élastiquement traversant un orifice ménagé dans la plateforme d'impression au-dessous de laquelle il rencontre les moyens de libération qui commandent l'encliquetage, et le montant (51) le moins chargé élastiquement étant disposé au-dessus d'un autre orifice ménagé dans la plateforme d'impression au-dessus duquel, dans sa position correcte d'impression, un bord de la feuille à imprimer est placé de manière à empêcher la pénétration du montant le moins chargé élastiquement dans ledit autre orifice, de sorte que lors du déplacement de la traverse en antagonisme à l'action élastique des montants de support chargé élastiquement, dans le cas d'une feuille incorrectement placée pour l'impression, le montant le moins chargé élastiquement peut pénétrer dans ledit autre orifice et une force est exercée sur le montant le plus chargé élastiquement qui est insuffisante pour actionner les moyens de libération, tandis que si la feuille est correctement placée pour l'impression, la résistance de la feuille au mouvement du montant le moins chargé élastiquement dans ledit autre orifice permet le mouvement du montant le plus chargé élastiquement pour actionner les moyens de libération, ce qui autorise le déclenchement d'un cycle d'impression.

2. Machine suivant la revendication 1, caractérisée en ce que les moyens de libération comprennent un levier pivotant (37) dont une extrémité est en contact avec le montant le plus chargé élastiquement, la rotation du levier par le mouvement de ce montant déplaçant une tige à rappel par ressort faisant partie de l'encliquetage, de manière à libérer le mécanisme d'entraînement d'impression.

3. Machine suivant la revendication 1 ou 2, caractérisée en ce qu'elle comporte un bras (71), supporté de façon pivotante, qui est en contact avec la traverse du pont et dont le pivotement déplace la traverse en antagonisme à l'action de rappel des montants du pont chargés élastiquement, le pivotement de ce bras étant commandé par un élément mobile qui est actionné par l'opérateur.

4. Machine suivant l'une quelconque des revendications précédentes, caractérisée en ce que le mécanisme d'entraînement d'impression comprend une poulie entraînée (3) qui effectue une révolution complète pour chaque cycle d'impression et en ce que la tige à rappel par ressort de l'encliquetage est poussée vers l'axe de rotation de la poulie, l'encliquetage comprenant en outre un bras (11) monté de façon pivotante sur la poulie et qui avance au-delà de la périphérie de la poulie où il vient en contact avec la tige en antagonisme à l'action de son ressort de rappel libérant la poulie pour permettre sa rotation.

5. Machine suivant la revendication 4, caractérisée en ce que le bras est logé et peut pivoter à l'intérieur d'une fente radiale (13) ménagée dans la poulie, en antagonisme à l'action d'un ressort de rappel (21), de sorte que vers la fin d'une révolution de la poulie entrainée, le bras vient en contact avec la tige et la ressort de rappel du bras est comprimé pour amortir la partie finale du mouvement de la poulie entrainée.

6. Machine suivant la revendication 4, ou la revendication 5, caractérisée en ce que la poulie entrainée comporte, dans une de ses faces, un guidage de came (35) qui reçoit un palpeur de came, ce dernier effectue un mouvement de va-et-vient pendant la rotation de la poulie, de manière à 'entraîner le compteur du mécanisme d'impression et l'avance du ruban.

7. Machine suivant la revendication 6, caractérisée en ce que la poulie comporte une denture d'engrenage périphérique qui engrène avec un pignon (33) qui entraîne le mécanisme d'impression, pour effectuer l'impression sur la feuille placée sur la plateforme d'impression.

Ansprüche

1. Druckmaschine zum Drucken von Zeichen auf Blattmaterial, das auf einer Druckplattform (45) der Maschine angeordnet ist, mit einem rotierenden Antriebsmechanismus mit einer Feststellvorrichtung (7) zum Verriegeln des Mechanismus, mit einer Freigabeeinrichtung, die betätigbar ist, um die Feststellvorrichtung außer Anlage zu bringen, um dadurch den Antriebsmechanismus freizugeben, und mit einer Betätigungseinrichtung (41) zum Betätigen der Freigabeeinrichtung, wobei die Betätigungseinrichtung (41) zum Fühlen des Vorhandenseins oder Fehlens eines zu bedruckenden Blattes mechanische Fühlelemente (43) aufweist, welche, wenn ein Blatt zum Drucken nicht richtig festgelegt ist, entsprechend angeordnet werden, um eine Betätigung der Freigabeeinrichtung zu verhindern, während, wenn ein Blatt zum Drucken richtig festgelegt ist, die Fühlelemente entsprechend angeordnet werden, um eine Betätigung der Freigabeeinrichtung zu ermöglichen, um dadurch einen Druckzyklus einzuleiten, dadurch gekennzeichnet, daß die mechanischen Fühlelemente (43) der Betätigungseinrichtung (41) eine Brücke (47) aufweisen, die an der Druckplattform (45) angebracht ist und ein Querteil (53) und durch Federn unterschiedlich belastete Haltestützen (49, 51) hat, wobei die durch eine stärkere Feder belastete Haltestütze (49) durch eine Öffnung in der Druckplattform (45) verläuft, unter welcher sie an der Freigabeeinrichtung anliegt, welche die Feststellvorrichtung (7) betätigt, und wobei die durch eine schwächere Feder belastete Haltestütze (41) über einer weiteren Öffnung in der Druckplattform (45) angeordnet ist, über welcher in der richtigen Druckposition ein Rand eines zu bedruckenden Blattes festgelegt ist, um eine Bewegung der durch eine schwächere Feder belasteten Haltestütze (51) in der weiteren Öffnung zu verhindern, wodurch bei einer Bewegung des Querteils (53) entgegen der Federbelastung der Haltestützen (49, 51), wenn das Blatt zum Drucken nicht richtig festgelegt ist, die durch eine schwächere Feder belastete Haltestütze (51) in die weitere Öffnung eindringen kann und eine unzureichende Kraft auf die durch eine stärkere Feder belastete Haltestütze (49) ausgeübt wird, um die Freigabeeinrichtung zu betätigen, während, wenn das Blatt zum Drucken richtig festgelegt ist, der Widerstand des Blattes bezüglich einer Bewegung der durch eine schwächere Feder belasteten Haltestütze (51) in die weitere Öffnung eine Bewegung der durch eine stärkere Feder belasteten Haltestütze (49) ermöglicht, um die Freigabeeinrichtung zu betätigen, um dadurch einen Druckzyklus einzuleiten.

2. Druckmaschine nach Anspruch 1, dadurch gekennzeichnet, daß die Freigabeeinrichtung einen verschwenkbaren Hebel (37) aufweist, welcher mit einem Ende an der durch eine stärkere Feder belasteten Haltestütze (49) anliegt, und daß bei einer Drehbewegung des Hebels (37) durch eine Bewegung der Stütze (49) ein federbelasteter Stab der Feststellvorrichtung (7) verschoben wird, um den Druckmaschinen-Antriebsmechanismus freizugeben.

3. Maschine nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, daß ein schwenkbar gehaltener Arm (71) vorgesehen ist, welcher an dem Querteil (53) der Brücke (47) anliegt, und daß bei einer Schwenkbewegung dieses Arms (41) das Querteil (53) entgegen der Vorspannung der federbelasteten Brückenstützen (49, 51) bewegt wird und durch ein bewegbares Teil gesteuert wird, welches von einer Bedienungsperson betätigt wird.

4. Maschine nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß der Antriebsmechanismus eine angetriebene Riemenscheibe (3) aufweist, welche für jeden Druckzyklus eine vollständige Umdrehung ausführt, und daß der federbelastete Stab der Feststellvorrichtung (7) in Richtung der Drehachse der Riemenscheibe (3) gedrückt wird, wobei die Feststellvorrichtung (7) einen Arm (11) aufweist, der an der Riemenscheibe (3) schwenkbar gehaltert ist und über deren Umfang hinaus vorsteht, wobei er an dem Stab anliegt, um die Riemenscheibe (3) zu sperren, und um deren Drehung zu verhindern, so daß bei einer Bewegung des Stabes entgegen dessen Vorspannfeder die Riemenscheibe (3) für eine Drehung frei kommt.

5. Maschine nach Anspruch 4, dadurch gekennzeichnet, daß sich der Arm (11) in einem radial verlaufenden Schlitz (13) in der Riemenscheibe (3) erstreckt und in dem Schlitz entgegen der Wirkung einer Vorspannfeder (21) schwenkbar ist, so daß zum Zwecke einer Beendigung einer Umdrehung der angetriebenen Riemenscheibe der Arm (11) an dem Stab anliegt, und die Vorspannfeder (21) des Arms (11) unter Spannung gesetzt wird, um den Endteil der Bewegung der angetriebenen Riemenscheibe (3) zu dämpfen.

6. Maschine nach einem der Ansprüche 4 oder 5, dadurch gekennzeichnet, daß die angetriebene Riemenscheibe (3) mit einer Kurvenscheibenführungsbahn (35) versehen ist, an welcher ein Stößel anliegt, welcher während einer Drehbewegung der Riemenscheibe (3) hin- und herbewegt wird, um den Druckmaschinen-Zähler und einen Farbbandtransport anzutreiben.

7. Maschine nach Anspruch 6, dadurch gekennzeichnet, daß die Riemenscheibe (3) am Umfang mit Zähnen versehen ist, welche mit einem Zahnrad (33) kämmen, welches einen Druchmechanismus zum Bedrucken des Blattes auf der Druckplatform (45) antreibt.

Drawing