Title of Invention

'A DEVICE FOR ON-LINE PRINTING ON RUNNING WRAPPER IN A WRAPPING MACHINE'

Abstract

This invention relates to a device for printing of packing date and other variable information on a wrapper in a continuously moving wrapping machine. The device comprises of two assemblies. The first assembly houses a metallic printing roller to which a replaceable stereos is fixed which bears the matter to be printed on wrapper, and an inking roller charged with solid ink or liquid ink. In case of solid ink, heating pads surrounding the ink roller, are provided to keep the ink tacky for application. A roller, mounted on a shaft, carries the wrapper, which comes in contact with stereos for printing. The assembly is mounted on guide bars, which enable moving of assembly across the breadth of the wrapper to position the printer at the required place on wrapper. Second assembly consists of support bracket on which plate bearing housing is provided on a shaft which is non-concentric to shaft bearing printing roller and takes its drive by a sprocket. Eccentricity between the shafts is adjusted so that linear speed of print head matches with the speed of wrapper at the time of printer.

Full Text

FIELD OF INVENTION This invention relates to a device for on-line printing on running wrapper in a wrapping machine. PRIOR ART Wrapping machines known in the art generally use on-line printers to print variable information like packing date, price, batch member, etc. which is often a statutory requirement. The printers which are used for printing such variable information are broadly of two basic types. The first type of such a commonly used printers, uses frictional drive taken from the running wrapper, by means of a rubber friction roller. Rotary printer mounted on the friction driven roller's spindle applies the print on the wrapper, when it comes in contact with it. As the printer head is rotated by friction between a fixed diameter rubber roller and flowing wrapper, the print is repeated after a pitch distance which is equal to the circumstance of the friction roller. A disadvantage of the above type of printers, is that during repetitive printing, the print does not appear at the same position with respect to the wrapper cut length which is referred to in the art as 'unregistered printing'. This unregistered printing by the above type of known machine, occurs due to the fact that the periodicity of the print has no relation to the wrapper cut length. Such unregistered printing may be acceptable for cheaper type of packets but is not acceptable for wrappers for wrapping products of reputed brand name. In the other type of printers known in the art for printing variable information on wrappers, printing is achieved by taking an electrical signal from a photocell detector which is focussed on a print mark that is pre-printed on the wrapper. Such printer, therefore enable registered printing at the marked position on the wrapper. On receipt of electrical signal from photocell detector, either a stepper motor or a variable speed motor is activated. This motor drives the printer head to impart print at the same position i.e. it carries out registered printing, on the wrapper. This is also achievable by means of inkjet printer. A disadvantage of the above type of printer is that these printers use expensive motorized drives with logic controls to set the speed of the printer equal to the speed of wrapper to prevent elongation of the printed characteristics. Another disadvantage of the above type of printer is that when the speed of the wrapping machine is altered, a readjustment is required of the speed of the printer motor to get registered printing without elongation of printed characters. Still another disadvantage of the above type of printer is that during inching operation of the machine, the machine may go out of alignment with the registered space on the wrapper and may therefore, not give the registered printing. Further disadvantage of the above type of the printers is that inkjet printer has very high initial cost and costly consumables. Yet further disadvantage of the above type of printers is that maintenance of electronics and electrical items is difficult for unskilled workers, which are generally employed for packaging. A printing device of the construction disclosed in the present invention is not known in the art. OBJECTS OF THE PRESENT INVENTION An object of the present invention is to provide an on-line printing device to print variable information on a wrapper at a fixed position in a continuously moving wrapping machine. Another object of the present invention is to provide an on-line printing device which is mechanical and does not use any complex electronics/electrical gadgets. Still another object of the present invention is to provide an on-line printing device which can be operated by an unskilled worker generally employed for packing. Further objects of the present invention is to provide a device for printing which involves low maintenance cost and low consumables. Still further object of the present invention is to provide a device for printing which enables registered printing i.e. printing at the earmarked space on the wrapper, without elongation of printed characters. STATEMENT OF INVENTION According to this invention there is provided a device for on-line printing on running wrapper in a wrapping machine, comprising:- (a) first assembly mounted on guide bars housing:- a metallic printing roller provided with replaceable rubber stereos or metallic types and mounted on shaft which can carry rotating member, an inking roller charged with ink and mounted on an eccentric spindle, wherein ink is selected from solid ink or liquid ink, a roller mounted on shaft which carries the wrapper which comes in contact with stereos for printing against the back support of roller, (b) second assembly comprises:- a plate fitted on support bracket on which bearing housing is mounted, a shaft provided in parallel and in adjustable eccentric position with shaft, a sprocket driving shaft in 1:1 ratio, a rotating lever having roller that fits into the slot of rotating member mounted on shaft. DESCRIPTION OF FIGURES. The invention will now be illustrated with accompanying drawings which illustrates an embodiment of the present invention. It is to be understood that the objects of the present invention are realizable through variant embodiments employing the concepts and features of the present invention. The drawings are therefore not intended to be taken restrictively to imply any limitation on the scope of the present invention. In the accompanying figures. Fig. 1: shows the device of the present invention Fig. 2: shows the details of assembly housing printing roller and inking roller. Fig. 3: shows the working of device. DESCRIPTION OF INVENTION w.r.t. DRAWINGS Referring to fig. 1 the device of the present invention comprises a housing assembly (8) which houses printing roller (1) and inking roller (4). The details of this assembly are shown in fig. 2 and are given in the description that follows in succeeding paragraph. Another assembly of the device consists of support bracket (11) on which plate (12) is mounted. On this plate (12), bearing housing (13) is provided, which is placed opposite to shaft (3) so that shaft (15) and shaft (3) are parallel to each other but are non-concentric. The eccentricity of the two shafts (3,15) can be varied as per requirement by moving the plate (12) up and down on bracket (11) and fixing screws (16,17). Shaft (15) takes drive from machine by sprocket (18) in 1:1 ratio. On the other side of the shaft, is a rotating lever (19) that has a roller (20) that fits into the slot of rotating member (10) mounted on shaft (3). Referring to fig.2, the printing roller (1) housed in the assembly (8), can be a metallic roller to which rubber stereos (2) is fixed. This stereos (2) bear the matter to be printed on wrappers. These stereos (2) are replaceable depending upon the text of the matter to be printed on wrappers. Alternatively, in lieu of rubber stereos, metallic types can be used. The roller (1) is mounted on shaft (3) by means of parallel key over which it can freely slide. The stereos (2) come in light contact with inking roller (4) mounted on an eccentric spindle (5) over which it is free to rotate. Eccentricity in spindle (5) is used for changing contact pressure between stereos (2) and the inking roller (4). The inking roller (4) can either be charged with liquid ink or it may contain solid ink. In case solid ink is used, heating pads are provided inside the assembly (8) to surround the inking roll and types to keep them warm by radiation so that ink becomes tacky for application. The stereos (2), during a part of the rotation of the roller (1), come in contact with wrapper which is flowing continuously on its path guiding over roller (6) mounted on shaft (7). The stereos (2) press over the wrapper against the back support of roller (6). This action transfers the print on the wrapper. The housing assembly (8) is mounted on guide bars (9) which allows the housing (8) to be shifted across the breadth of the wrapper to position the printer at the required place on the wrapper. The shaft (8) carries a rotating member (10) that has a uniform longitudinal slot (shown in fig. 2(a)). OPERATION OF THE DEVICE Sprocket (18) is rotating the lever (19) at a uniform rotary speed that is equal to the speed of the machine so that one cycle of machine corresponds to one rotation of lever (19). Since roller (20) of lever (19) is engaged in the slot of rotating member (10), the rotary motion is transferred to shaft (3). There being an eccentricity between shaft (15) and (3), it forms an eccentric drive and the uniform rotary motion of (15) imparts accelerating motion to member (10). As print roller (1) is mounted on shaft (3), it rotates with nonuniform motion of the printer. Eccentricity between shaft (15) and shaft (3) can be so adjusted that the linear speed of the print head matches with the speed of the wrapper at the time of printing. It is to be noted that the present invention is susceptible to modifications, changes and adaptations by those skilled in the art. Such variant embodiments incorporating the concepts and features of the present invention, are intended to be within the scope of the present invention, which is further set forth under the following claims:- I CLAIM: 1. A device for on-line printing on running wrapper in a wrapping machine, comprising :- (a) first assembly (8) mounted on guide bars (9) housing:- a metallic printing roller (1) provided with replaceable rubber stereos (2) or metallic types and mounted on shaft (3) which can carry rotating member (10), an inking roller (4) charged with ink and mounted on an eccentric spindle (5), wherein ink is selected from solid ink or liquid ink, a roller (6) mounted on shaft (7) which carries the wrapper which comes in contact with stereos for printing against the back support of roller (6), (b) second assembly, comprises :- a plate (12) fitted on support bracket (11) on which bearing housing (13) is mounted, a shaft (15) provided in parallel and in adjustable eccentric position with shaft (3), a sprocket (18) driving shaft (15) in 1:1 ratio, a rotating lever (19) having roller (20) that fits into the slot of rotating member (10) mounted on shaft (3). 2. A device as claimed in claim 1 wherein heating pads are provided to surround inking rolls and types to make ink tacky for application, when solid ink is used. 3. A device for on-line printing on running wrapper in a wrapping machine as substantially described and illustrated herein.

Documents:

813-del-2003-abstract.pdf

813-del-2003-claims.pdf

813-del-2003-complete specification (granted).pdf

813-del-2003-correspondence-others.pdf

813-del-2003-correspondence-po.pdf

813-del-2003-description (complete).pdf

813-del-2003-drawings.pdf

813-del-2003-form-1.pdf

813-del-2003-form-19.pdf

813-del-2003-form-2.pdf

813-del-2003-gpa.pdf

813-DEL-2003-PCT-409.pdf