Feeding device for a continuous form

Abstract

 A feeding device (12) for a paper strip or a continuous paper form (13) comprising a transport assembly (31), including two motor rollers (32, 33) of identical diameter synchronous in the rotations and two pinch rollers (36) and in which the motor rollers (32, 33) are provided for engagement with two lateral nipping areas of the form (13) and the pinch rollers (36) are engageable with the nipping areas against the motor rollers (32, 33) for the transmission of dragging forces to the sides of the paper form (13). The feeding device (12) further comprises a stiffening assembly (19) for transversally engaging the paper form (13), upstream of the motor rollers (32, 33) and the pinch rollers (36), and in which the stiffening assembly includes bending and contrast elements (44, 46, 48) to deflect the paper form longitudinally from its direction of movement.

Description

[0001] The present invention relates to a feeding device for advancing, in a straight path, a continuous form, for example, a paper strip or a continuous un-holed paper form.

[0002] The feeding devices represent a fundamental component on systems for the automatic processing of documents provided as continuous paper forms. The pages of the documents are firstly printed on the forms and are thereafter separated by cutting equipments, generally of reciprocating motion type.

[0003] Systems for the automatic processing of documents employing continuous paper forms with transport holes into the sides are widely used. The holes are engaged by tractor pins for a positive feeding of the form and it ensures precision, high operating speed and high reliability.

[0004] Processing systems employing un-holed holed continuous paper forms have the advantages of a lower cost of the forms, the lacking of trimming operations and elimination of waste of paper. Sometimes the feeding of holed continuous forms by means of devices devoid of tractor pins could be suitable.

[0005] The feeding devices for advancing continuous paper forms and devoid of pin traction include transport assemblies having motor rollers and pinch rollers. It is well known that the friction-feed technology can cause deviations of the form with respect to the direction of advancement.

[0006] The problem of alignment is particularly serious in feeding devices for cutting equipments which operate during temporary stops of the paper form and which submit the section to be cut to high accelerations and breakings. For wide formats, high drag forces should be transmitted on nipping areas of the form adjacent to the edges. Irregularities in the traction or uneven deformations of the paper form tend to cause skewing during the advancement with consequences on the cutting and risks of jams and tears. The irregularities can depend on dimensional differences of the motor rollers due to working spread, wear on the motor rollers or the pinch rollers, dirt, or differences regarding the pinch rollers, as amount and/or direction of the pressure load.

[0007] Transport assemblies including a motor roller and a single pinch roller working on the longitudinal axis of the paper form have also been proposed. This approach has the disadvantage that, for high operating speeds, the sides of the form will rise with respect to the central areas with chattering of the paper in unacceptable way.

[0008] The prior art discloses feeding devices for continuous strips or un-holed paper forms which include particular solutions for advancing the strips or the forms along a straight path.

[0009] US Patent 5,323,945 relates, for example, to a system of transport for a strip of thermal paper providing a motor roller divided in three sections. The lateral sections of the roller are connected in the rotation with a differential mechanism such that the average velocities of the lateral sections are equal to the average velocity of the central section, whereas the instantaneous velocity can be different.

[0010] European Patent Application EP 1 187 149 discloses a feeding device for continuous paper forms comprising a motor roller having two lateral sections connected each other through gears of compensation.

[0011] Further, feeding devices for continuous paper forms providing two servomotors to actuate two respective roller motors in engagement with lateral areas of the form have also been proposed. The servomotors respond to position sensors, which read marks printed on the sides of the form for regulating the instantaneous velocities of the motor rollers to correct any misalignment of the form from the nominal path.

[0012] The above summarized proposals result rather complex and expensive.

[0013] Object of the present invention is to accomplish a feeding device for advancing in a straight path a paper strip or continuous paper form and, more specifically, for un-holed continuous forms or for forms whose perforations are not used, which results reliable and relatively inexpensive and which ensures optimal alignment in serious conditions of velocity and stress.

[0014] This object is constituted by the feeding device for a continuous paper form and, more specifically, for an un-holed continuous form at the sides or for forms whose perforations are not used, according to the main claims.

[0015] The characteristics of the invention will become clear from the description that follows made merely by way of non-restrictive example, with the aid of the attached drawings, in which:

Fig. 1 represents a schematic perspective view of a cutting equipment for a paper strip or continuous paper form, which includes a feeding device according to the invention;

Fig. 2 shows schematically a sectioned side view and control circuits of the cutting equipment and the feeding device represented in Fig. 1;

Fig. 3 shows details in an enlarged scale of the feeding device of Fig. 1;

Fig. 4 represents other details in an enlarged scale of the device of Fig. 1;

Fig. 5 is a side view sectioned and enlarged of details shown in Fig. 2;

Fig. 6 is a side view sectioned and enlarged of other details shown in Fig. 2; and

Fig. 7 represents a schematic plan view of the cutting equipment and the feeding device of Fig. 1.

[0016] With reference to the figures 1, 2 and 7, a cutting equipment or cutter represented with 11 comprises a feeding device 12 for a paper strip or continuous paper form 13.

[0017] The cutting equipment 11 includes a frame 14, an input moving device 15, a loop forming device 16, a trimming mechanism 17 for the sides of the paper form, a cutting mechanism 18 for the transversal cutting of the form, build as a module, and an extraction mechanism 19 for the sheets to be separated from the paper form.

[0018] The input moving device 15 is actuated by an input motor 20, while the loop forming device 16 includes a loop sensor 21 associated to a pre-defined length of the loop. The cutting mechanism 18 includes a guillotine like blade, which is subject to reciprocating motion and is operated, through an eccentric cam, by a cutting motor 22. A single motor 23 actuates the trimming mechanism 17 and the extraction mechanism 19, while a traction motor 24 actuates the feeding device 12.

[0019] The cutting equipment 11 has a structure similar to the removable module of the equipment described in the Italian Patent Application N. TO2003A000371, filed on 20.05.03 in the name of Tecnau S.r.l, which is incorporated herein by reference.

[0020] Support elements, comprising for example a pair of transversal steel sheets 26 and 27 and a series of longitudinal bars 28, hold the paper form 13 between the feeding device 12 and the loop forming device 16 along a movement surface 29. The sheets 26 and 27 are suitably shaped and in which the sheet 26 is adjacent to the device 16, whereas the sheet 27 is adjacent to the device 12.

[0021] The feeding device 12 is arranged upstream of the trimming mechanism 17 and the cutting mechanism 18 and has the function of feeding, in intermittent way, the section of paper form 13 to be cut.

[0022] The continuous paper form 13 is devoid of traction holes, whereas the feeding device 12 and the input moving device 15 use a transport assembly of friction type.

[0023] Nevertheless, the equipment 11 can use, as an alternative, paper forms with standard transport holes, but in which the holes are not used for the feeding.

[0024] According to the invention, the feeding device 12 comprises a transport assembly 31 which includes two motor rollers 32 and 33 (Figs. 3 and 4) of identical diameter and two pinch rollers 34 and 36. The rollers 32 and 33 are coaxial and are provided for engagement with two nipping areas of respective lateral bands 371 and 37r of the paper form 13, adjacent to the longitudinal edges of the form. The pinch rollers 34 and 36 are engageable with the nipping areas of the bands 371 and 37r against the motor rollers and bear on the paper with a pressure suitable for the transferring of dragging forces to the sides of the form 13. The motor rollers 32 and 33 are mounted on a motor shaft 38 perpendicularly to the feeding direction of the form 13 and are synchronous in the rotation, for instance through adjustable fixing on the shaft 38.

[0025] According to a characteristic of the present invention, the feeding device 12 includes a stiffening assembly 39, which is provided for engagement with the paper form 13 upstream of the relative transport assembly 31. The device 12 further comprises two lateral limiting members 41 and 42 for guiding the longitudinal edges of the form within given limits. The members 41 and 42 are arranged at the sides of the motor rollers 32 and 33 and are supported by a prismatic crossbar 43 with possibility of adjustment in accordance with the width of the form 13.

[0026] The stiffening assembly 39 defines a longitudinal bend of the continuous paper form 13, which increases the transversal rigidity of the form. During the feed and as consequence of the bending, the unavoidable differences of tension between the nipping areas and the rollers will cause very limited transversal deformations of the paper form 13, with possibility of micro skids in the stressed areas of the form, while the section of form subject to the traction is maintained in axis with the direction of feed.

[0027] According to another characteristic of the invention, the stiffening assembly 39 is of a dynamic control type and includes yielding elements to modify the amount of longitudinal bend due to the tension of the paper form 13, in the use.

[0028] The feeding device 12 is sized so that the distance between the stiffening assembly 39 and the transport assembly 31 is relatively short to dynamically maintain the continuous paper form 13 well stiffened between the area of engagement with the assembly 39 and the areas of engagement with the motor rollers 32 and 33. Further, the device 12 is located close to the cutting mechanism 18

[0029] Specifically, the stiffening assembly 39 includes transversal bends 44, 46 and 47 in the sheet 27 and a contrast bar or contrast element 48, which extend perpendicular to the direction of feed. The bends 44, 46 and 47 define a substantially "V" shaped seat in the lower part of the sheet 27, which is adapted to receive the contrast bar 48 and in which the bends 44 and 46 depart downwardly from the movement surface 29, and the bend 47 corresponds to the vertex of the "V."

[0030] In the use, the paper form 13 (Figs. 1 and 5) slides upon the sheets 26 and 27 and the longitudinal bars 28, guided upwardly by guide shoes 49, while the contrast bar 48 deflects downwardly the portion of form interposed between the bends 44 and 46, through a waved or "V" shaped path.

[0031] As for the dynamic control of the longitudinal bending of the paper form 13, a sustaining structure yieldingly supports the contrast bar 48 through an elastic suspension. Suitably, the contrast bar 48 (Figs. 1 and 4) is mounted on a support rod 51, which is fulcrumed at a side 52 of the frame 14. In detail, the bar 48 is guided in a groove 53 of the rod 51 and the elastic suspension comprises a series of springs 54. The springs 54 are arranged along the axis of the rod 51 and push downwardly the bar 48, against end stop elements of the rod 51 not shown in the drawings.

[0032] In operating conditions, the rod 51 bears on reference stops of the frame, parallel to the sheet 27 and is provided for lifting with respect to the sheet 27 to make easier the mounting of the paper form 13 between the components of guide and movement of the equipment 11. The end stop elements are adjustable so as to make the contrast bar 48 to project more or less with respect to the bends 44 and 46 for an adjustable longitudinal deflection of the form 13, when the rod 51 is depressed parallel to the sheet 27. The load of the springs 54 can also be suitably adjusted.

[0033] Support and guide elements hold the paper form 13 (Figs. 5, 6 and 7) adjacent to the areas nipped between the motor rollers and the pinch rollers and limit upwardly the path of the form. The support and guide elements include, downwardly, a pair of plates 56 and 57 and shoes 58 supported by the crossbar 43 and, upwardly, shoes 61 mounted on a prismatic crossbar 62.

[0034] In detail, the plates 56 and 57 are adjacent to the limiting members 41 and 42 and include respective windows, through which the nipping sectors of the motor rollers 32 and 33 project upwardly. The plates 56 and 57 and the shoes 58 are coplanar each other and adjacent to the bend 46.

[0035] In the embodiment of the drawings, the motor shaft 38, of support for the motor rollers 32 and 33, is actuated in the rotation by the traction motor 24 through a belt and pulley coupling.

[0036] The pinch rollers 34 and 36 (Figg. 3, 6 and 7) are rotatable on respective brackets 66, which are pivoted on blocks 67, 68, in turn supported by the crossbar 62 with possibility of adjustment. Corresponding springs 69 urge the pinch rollers 34 and 36 toward the motor rollers 32 and 33 through the brackets 66.

[0037] The load of the springs 69 is adjustable through nuts 71 as function of the characteristics of the paper and the springs. Moreover, the pinch rollers 34 and 36 can be spaced away from the motor rollers through knobs or levers 72 and rods 73, against the action of the springs 69, to make easier the insertion of the paper form 13.

[0038] The motor rollers 32 and 33 are of a metallic material, identical in the diameter according to the spread of a fine working, and have a hardened surface with controlled roughness for high adherence with the paper form. The pinch rollers 34 and 36 are also metallic with hardened surface whereas the load of the springs 69 is particularly high, of around 2-3 kg. It ensures optimal and reliable conditions of transport of the form 13. The lateral plates 41 and 42 are in a light alloy with surface hardened by deep anodization for a good sliding of the paper form and reduced wear. As an alternative to the metallic materials, composite materials or other hard materials can be employed.

[0039] The input moving device 15 (Figs. 1, 2 and 7) comprises a transport assembly 76, with two motor rollers and two pinch rollers provided for engagement with lateral nipping areas of the paper form 13. As an alternative, the device 15 can provide a single motor roller and a single pinch roller, provided for engagement with an axial area of the form 13.

[0040] As shown in the figures, the motor rollers and the pinch rollers of the transport assembly 76 are mounted on structures identical to the ones of the rollers 32, 33 and 34, 36. Thus, the motor rollers and the pinch rollers of the member 76 include a motor shaft 77 connected to the input motor 20 and, respectively, blocks 78 and 79 supported by a prismatic crossbar 81. Similar connections are provided in the case of use of a single motor roller and pinch roller.

[0041] Plates 82 and 83 and shoes 84 located below the nipping area of the transport assembly 76 and, shoes 87 above the nipping area are also provided. The plates 82 and 83 and the shoes 84 are supported by a prismatic crossbar 86, whereas the shoes 87 are supported by the blocks 78 and 79 and in which the plates 82 and 83 include respective windows of access to the upper sectors of the motor rollers. Further, in the input area, a bar 88 having two flanges 89 and 91 and a tile 92 are provided for transversally guiding the paper form 13 there between.

[0042] The portion of the equipment 11 arranged below the longitudinal bars 28 is provided for lodging typical control devices for the paper form 13, as OMR (optic mark reader), BCR (bar code reader) or a video camera.

[0043] The longitudinal bars 28 are mounted between the sheets 26 and 27 by means of spring ends with possibility of removal for an easy access to the control devices of the paper form. Optionally, longitudinal support sheets engaged in adjustable seats of the sheets 26 and 27 can be provided. The shoes 49 are mounted on a prismatic crossbar 92 and, for an easy introduction of the form 13, the crossbar 92 is fulcrumed on the side 52 of the frame 14 with possibility of lifting jointly with the support rod 51.

[0044] The cutting equipment 11 comprises an electronic control module 93 similar to the one of the above mentioned Patent Application N. T02003A000371. In detail, the motors 20, 24 and 22 (Fig. 2) are integrated with encoders, which supply position signals St1 and St2 for the entering sections of the paper forms and for the sections to be cut, respectively, and signals St3 associated with the position of the blade. Further, the electronic module 93 is synchronized by series of marks, printed on the paper form 13 and recognized by position sensors not shown in the drawings.

[0045] Servo control circuits 94, 96 and 97 drive the motors 20, 24 and 22, respectively: the circuit 94 for the input moving mechanism 15 is servoized to the velocity of the portion of paper form to be cut and to signals from the loop sensor 21, while the circuit 96 for the control of the feeding device 12 is servoized to the velocity and the position of the blade.

[0046] The servo control circuit 94 drives the input moving device 15 so as to introduce the paper form 13 at instantaneous velocities having small fluctuations with respect to a reference average velocity. The entering form 13 results not very stressed, whereas the skew in input is neutralized by the loop forming device 16.

[0047] The structure of the above described feeding device 12 makes a paper form 13 of standard width by 20" to advance with a mean velocity of the order of 3 m/sec. and a peak velocity of 5÷6 m/sec. The paper form 13 advances along the equipment 11 in axis with the direction of movement, without skipping with respect to the movement surface 29 and without chattering of the portions to be cut. The performances are reliable maintained for an extended life and adverse conditions.

[0048] As a matter of fact, the feeding device 12 ensures operating conditions for the paper form 13 similar to the ones of feeding devices with pins traction and using forms with side transport holes. Further, during the start and stop, the contrast bar 48 modifies the deflection of the paper form with anti-jerk function in view of the elastic suspension without substantial increasing of the acceleration and braking times.

[0049] Naturally, the principle of the invention remaining the same, the embodiments and the details of construction can be widely varied with respect to what has been described and illustrated, by way of non-limitative example, without by this departing from the scope of the present claimed invention.

[0050] The feeding device of the invention can specifically be used in other equipment for the processing of paper forms as, for instance, longitudinal cutting and separation equipments (merger), perforating or punching equipments and in high speed printing equipments. In the case of a punching equipment, the punch could be powered by a servoized actuation motor, and the motor rollers or the active sections of a motor roller will be driven by a servomechanism servoized to the actuation motor.

[0051] A punching equipment of the above type is described in the Italian Patent Application N. TO2003A000418, filed on 04.06.03 in the name of Tecnau S.r.l.

[0052] The feeding device 12 can provide, as an alternative to the two motor rollers 32 and 33, a single, full width motor roller with lateral active sections which nip the side bands of the paper form 13 by means of a pair of pinch rollers similar to the rollers 34 and 36.

[0053] In addition to the described lateral pairs of motor rollers and pinch rollers, the feeding device 12 can provide a third central pair of motor roller and pinch roller with nipping of an axial area of the paper form 13.

[0054] Instead of the "V" shaped bending of the sheet 27 others deflection members can be provided, as represented by a single bend of the sheet, or by an element of deflection and a contrast element or by deflection through a plurality of bending bars and one or more elements or bars of contrast, to ensure the transversal stiffening.

[0055] Alternatively, the stiffening assembly can include a contrast bar projecting from the movement surface 29 and one or more deflection bars of the paper form 13 mounted on a frame of support, upstream and downstream of the contrast bar, not shown in the drawings. In this case, the anti-jerk function can be obtained by means of elastic suspensions on the contrast bar and/or on one or on both the deflection bars.

[0056] Further, the dynamically controlled stiffening assembly according to the invention is advantageously employable in feeding devices different from the one above described. An example is represented by the use of a stiffening assembly for advancing paper forms of limited width and in which the transport is effected trough a single transport pair constituted by a motor roller and pinch roller, which operates on a central nipping area of the paper form.

Claims

1. A feeding device (12) for a paper strip or a continuous paper form (13) comprising a transport assembly (31), the said feeding device being characterized in that the transport assembly includes two motor rollers (32, 33) synchronous in the rotations, or two active lateral sections of a motor roller of identical diameter, and two pinch rollers (36) and in which
the motor rollers (32, 33) or the active sections of a motor roller are provided for engagement with two lateral nipping areas of the form (13); and
the pinch rollers (36) are engageable with said nipping areas against the motor rollers (32, 33) or against the active sections of a motor roller for the transmission of dragging forces to the sides of the paper form (13);
the said feeding device (12) further comprising a stiffening assembly (19) for transversally engaging said form (12), upstream of the motor rollers (32, 33) or the active sections of a motor roller and the two pinch rollers (36), said stiffening assembly including bending and contrast elements (44, 46, 48) to deflect the paper form longitudinally from its direction of movement.

2. Device according to claim 1, wherein a section of the paper form is moved along a movement surface (29) substantially horizontal, said device being characterized in that the bending and contrast elements include a first deflection element (44) which deflects downwardly a section of the paper form (13), a contrast element (48) which opposes upwardly another section of the paper form deflected downwardly and a second deflection element (46) which deflects toward the movement surface (29) a further section of the paper form deflected toward the movement surface, and in which the contrast element (48) is carried by a support member (51) provided for lifting with respect to the movement surface (29) to make easier the insertion of the paper form (13) in the said device (12).

3. Device according to claim 1 or 2, characterized in that the stiffening assembly (39) comprises yielding elements for dynamically adjusting the longitudinal bend of the paper form (13).

4. Device according to claims 2 and 3, characterized in that said yielding elements comprise a plurality of springs (54) interposed between the contrast element (48) and said support member (51).

5. Device according to one of the preceding claims, characterized in that said bending and contrast elements define a path of the paper form (13) substantially of "V" shape in section, said bending and contrast elements comprising a shaped plate (27) and a contrast bar (48), in which the said plate defines two deflection bends (44,46) and a connecting bend (47), the deflection bends (44, 46) and the connecting bend (47) being arranged at the lugs of the "V" and between the deflection bends, respectively, and in which the contrast bar (48) is arranged at the vertex of the "V" path.

6. Device according to one of the preceding claims, further including a pair of lateral guides (41, 42) for guiding the longitudinal edges of the paper form (13), said guides (41, 42) being arranged adjacent to the motor rollers (32, 33) or the active sections of a motor roller.

7. Device according to one of the preceding claims, characterized in that the motor rollers (32, 33) or the active sections of a motor roller and the pinch rollers (34, 36) are in material hardened at the surface and in which the motor rollers (32, 33) or the active sections of a motor roller have pre-defined roughness for high adherence with the paper form (13).

8. Device according to one of the preceding claims, characterized in that it is used in a cutting equipment (11) or in punching equipment with blade or punch, respectively, powered by a servoized actuation motor (22), the said motor rollers or the active sections of a motor roller being driven by a servomechanism servoized to said actuation motor and located close to the cutting or punching equipment.

9. Device according to one of the preceding claims, characterized in that it is used downwardly of a device (16) for forming and/or controlling a loop of the said paper form (13).

10. Feeding device for a continuous paper form comprising a pin-less transport assembly (31), said feeding device being characterized in that it comprises a stiffening assembly (19) with longitudinal bend having dynamic control elements (48, 54) provided for engagement with the paper form, upstream of the said transport (31) assembly.

11. Feeding device for a continuous paper form comprising a pin-less transport assembly (31), said feeding device being characterized in that it comprises a stiffening assembly (19) provided for engagement with the paper form (13), the said stiffening assembly including bending and contrast elements (44, 46, 48) to longitudinally deflect the paper form from its direction of movement and a support member for at least one of the bending and contrast elements (48), said support member being provided for lifting said at least one of the bending and contrast elements (48) with respect to the other bending and contrast elements (44, 46) to make easier the insertion of the said paper form (13).

Drawing