GB2436316A

GB2436316A - Method of printing

Info

Publication number: GB2436316A
Application number: GB0605559A
Authority: GB
Inventors: Pedro Carey Landers; Lain Ansell; Nick John Collier
Original assignee: Markem Technologies Ltd
Current assignee: Markem Imaje Industries Ltd
Priority date: 2006-03-20
Filing date: 2006-03-20
Publication date: 2007-09-26
Also published as: GB0605559D0

Abstract

A method of printing including, where an inked carrier ribbon (15) is provided as a storage spool (25) in which a ribbon (15) is inked on the radially internally wound surface (15a) of the ribbon (15), threading the ribbon (15) in a first ribbon path around ribbon guides (41, 42, 50, 51), and where the inked carrier ribbon (15) is provided as a storage spool (25) in which the ribbon (15) is inked on the radially externally wound surface (15b) of the ribbon (15), threading the ribbon (15) in a second ribbon path around the ribbon guides (41, 42, 50, 51), and selecting a first or second operating mode, and when the first mode of operation is selected and the ribbon (15) is inked on the radially internally wound surface (15a), operating the drive motor (30) to rotate the ribbon take-up spool (28) in a first sense of rotation, and when the second mode of operation is selected and the ribbon (15) is inked on the radially externally wound surface (15b), operating the drive motor (30) to rotate the ribbon take-up spool (28) in a second sense of rotation opposite to the first sense of rotation.

Description

Title: Method of Printing

Description of Invention

This invention relates to a method of printing utilising a printing apparatus of the kind including at a printing station, a print head having an array of printing elements which are selectively energisable, to remove pixels of ink from an inked carrier ribbon to print an image on a substrate.

Such printing apparatus are known for handling carrier ribbon which is inked on either a radially internally wound surface or alternatively a radially externally wound surface, of a storage spool. A ribbon feed path from a storage to a take-up spool through a ribbon feed path is configured for use depending upon whether the ribbon is radially internally or externally inked.

Thus a purchaser of a known printing apparatus which is configured for use with ribbon spools in which the ribbon is radially internally inked, cannot use ribbon spools in which the ribbon is radially externally inked, and vice versa, at least without reconfiguring the printer which would require an engineer's expertise. S...

S'. According to the invention we provide a method of printing utilising a printing apparatus including at a printing station, a print head having an array of printing elements which are selectively energisable, to remove pixels of ink from an inked carrier ribbon to print an image on a substrate, the apparatus further including a storage spool for ribbon to be used in printing and a take-up spool for used ribbon and a ribbon feed path including a plurality of ribbon guides for the ribbon between the storage and take-up spools, through the printing station where the ribbon is interposed between the print head and the substrate, and there being a drive motor for driving at least the take-up spool for taking up used ribbon from the printing station in a ribbon feed direction, and the method including, where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on the radially internally wound surface of the ribbon, threading the ribbon in a first ribbon path around the ribbon guides, and where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on the radially externally wound surface of the ribbon, threading the ribbon in a second ribbon path around the ribbon guides, and selecting a first or second operating mode, and when the first mode of operation is selected and the ribbon is inked on the radially internally wound surface, operating the drive motor to rotate the ribbon take-up spool in a first sense of rotation, and when the second mode of operation is selected and the ribbon is inked on the radially externally wound surface, operating the drive motor to rotate the ribbon take-up spool in a second sense of rotation opposite to the first sense of rotation.

Thus the method of the present invention enables a printing apparatus to be used for both inked radially internally wound ribbon spools and inked radially externally ribbon spools without any major reconfiguring of the printing apparatus, but simply requiring re- threading of the ribbon and the selection of an appropriate operating mode, to change the printing apparatus for radially n... 20 internally or radially externally inked carrier ribbon. S... * S S...

* .. In a preferred arrangement, where the printing apparatus includes a drive :.:. motor for the storage spool, upon selection of the first operating mode, the storage spool drive motor may be operated to rotate the storage spool in the * * * 25 first sense of rotation and where the second operating mode is selected the * storage spool drive motor may be operated to rotate the storage spool in the second sense of rotation.

The printing apparatus may include a ribbon tension sensing mechanism which in use, senses the ribbon tension along the ribbon feed path and/or an encoded ribbon guide roller, which in use, senses ribbon feed speed, and the or each of the ribbon tension sensing mechanism and/or the encoded ribbon guide roller may provide input to a controller which controls ribbon tension and speed respectively around the ribbon feed path, by varying the rotational speed of the take-up spool motor and/or where provided, the storage spool drive motor, to maintain ribbon tension in the ribbon feed path and ribbon speed, between acceptable limits.

It will be appreciated that the operation and performance of the ribbon tension sensing mechanism and/or the encoded ribbon guide roller will be unaffected by whichever of the operating modes is selected.

The printing apparatus may include a substantially rectangular body member mounting the storage and take-up spools and the print head, the body member including a ribbon guide generally at each corner, with the storage and take-up spools being provided between a first pair of the ribbon guides and the printing station being provided between the other, second, pair of ribbon guides.

The method of the invention may include selecting the appropriate operational p'... 20 mode for handling inked radially internally wound or inked radially externally * . . . . . S...,. wound ribbon, by operating a simple switch which provides input to the * ** controller. However where the controller is programmable with printing :.:. parameters via an input device, the selected operating mode may be *5* programmed into the controller using the input device.

The input device may be a keypad which may be permanently or temporarily connected to the controller of the printing apparatus for programming the controller.

According to a second aspect of the present invention we provide a printing apparatus including at a printing station, a print head having an array of printing elements which are selectively energisable, to remove pixels of ink from an inked carrier ribbon to print an image on a substrate, the apparatus further including a storage spool for ribbon to be used in printing and a take-up spool for used ribbon, and a ribbon feed path including a plurality of ribbon guides for the ribbon between the storage and take-up spools, through the printing station where the ribbon is interposed between the print head and the substrate, and there being a drive motor for driving at least the take-up spool for taking up used ribbon from the printing station in a ribbon feed direction, and a mode selection device for selecting a first operating mode where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on a radially internally wound surface of the ribbon, and the ribbon is threaded in a first ribbon path around the ribbon guides, whereby in use, the drive motor is operated to rotate the ribbon take-up spool in a first sense of rotation, and for selecting a second operating mode where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on the radially externally wound surface of the ribbon, and the ribbon is threaded in a second ribbon path around the ribbon guides, whereby in use, the drive motor is operated to rotate the ribbon take-up spool in a second sense of rotation opposite to the first sense of rotation. S. * S * *5.

The printing apparatus may have any of the features of the printing apparatus described for use in the method of the first aspect of the invention.

An embodiment of a printing apparatus on which the method of the present : 25 invention may be performed will now be described with reference to the accompanying drawings in which:-FIGURE 1 shows a printing apparatus in accordance with the invention in a first operating mode; FIGURE 2 shows the printing apparatus of figure 1 in a second operating mode.

Referring first to figure 1 there is shown a printing apparatus 10 which includes a printing station 11 at which there is provided a print head 12. The print head 12 includes an array 14 of printing elements which are selectively energisable to produce heat, thereby to remove pixels of ink from an inked carrier ribbon and to deposit the pixels of ink as a row of pixels, onto an adjacent substrate (not shown), the inked carrier ribbon 15 being interposed between the print head 12 and the substrate at the printing station 11. Further rows of pixels are printed onto the substrate by relatively moving the substrate and print head 12 at the print station 11, and by presenting fresh ribbon 15 from which pixels of ink have not already been removed, to the print head 12, to build up an image.

In this example, the print head 12 is moveable at the printing station along a stationary or moving substrate, to effect a desired relative speed of relative movement between the print head 12 and the substrate for printing. This print head 12 movement is achieved by a toothed drive belt 20 which is entrained about a drive sprocket (not seen) and an idler pulley (not seen) the drive sprocket being driven by a print head drive motor 21 e.g. which is a stepper motor. After printing an image on a substrate, the print head 12 is moved back

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to a "home" position ready for the next print, by operating the drive motor 21, and hence moving the drive belt 20 in an opposite direction. *S.

In another embodiment, or indeed in another mode.of operating the printing apparatus 10 shown and described, the print head 12 is held stationary at the printing station 11 and relative movement between the print head 12 and substrate is achieved solely by movement of the substrate past the print head 12. In such an arrangement, the ribbon 15 too would be advanced past the print head 12 with the substrate, typically at the same or similar speed to the substrate.

In yet another embodiment, the print head 12 will move along the substrate during printing and the substrate will be moving through the printing station 11.

In this example, some ribbon 15 feed may be required during printing to ensure that fresh ribbon 15 is continuously presented to the print head 12.

As wil! be appreciated by those skilled in the art, in each case, a printing operation typically would involve moving and urging the print head 12 towards the substrate during printing of an image, and away from the substrate after printing, to facilitate the moving of the printed substrate away from the print station 11, and to facilitate the feeding of fresh substrate (and ribbon 15) at the printing station 11 in preparation for the next printing operation.

A supply of inked carrier ribbon 15 is provided as a storage spool 25 being ribbon wound about a former 26, which storage spool 25 is mounted, via a hub 27 on a drive shaft of a storage spool drive motor (not seen) so as to be rotatable by the drive motor. Used ribbon 15 i.e. ribbon 15 which has been used for printing, is taken up onto a ribbon take-up spool 28 being used ribbon wound about a former 29. The former 29 of the take-up spool 28 is mounted on a drive shaft of a take-up spool motor 30, via a hub 31, thereby to be S...

s.... rotatable by the drive motor 30. S *S

S S S

In this example, one or each of the ribbon storage spool drive motor and ribbon take-up spool drive motor 30 is a stepper motor, but one or other could :: 25 be a DC motor, or other kinds of motors may be utilised. The motors 30 are however controlled by a printing apparatus controller 32, and are operable to provide drive in either direction of rotation. In another example, only the ribbon take-up spool 28 may be driven by a drive motor, with there being, for example, a drive roller such as a Rogers roller, to impart movement to the ribbon 15 around the ribbon feed path. In each case, ribbon 15 is fed in a ribbon feed direction past the print head 12 at the printing station 11, which in the example illustrated is from left to right.

The controller 32 is operable to co-ordinate ribbon 15 movement, print head 12 movement where appropriate, and print head 12 operation, and is programmable as hereinafter explained with various printing parameters necessary for effecting printing.

The ribbon 15 passes from the storage spool 25 around a ribbon feed path to the take-up spool 28, through the printing station 11, there being a plurality of ribbon guides around which the ribbon 15 is threaded, to guide the ribbon 15 around the ribbon feed path.

It can be seen that in this example, the printing apparatus 10 includes a body member 40 which is plate-like, and the storage and take- up spools 25, 28 and the print head 12 and drive belt 20, and the entire ribbon feed path, are provided at one side of the plate-like body member 40. The body member 40 is generally rectangular, having a ribbon guide generally at each corner. S.

: 20 A first ribbon guide 41 is provided immediately adjacent the storage spool 25. SSS *

In this example, the first ribbon guide 41 is an encoder roller device for providing input to the controller 32 indicative of ribbon speed, for the purposes of controlling ribbon 15 speed, for example during printing where the print head 12 is held stationary during printing and the substrate and ribbon 15 are * : 25 moved past the stationary print head 12 to effect relative movement.

A second ribbon guide 42 is provided by a ribbon tension sensing mechanism, which includes a guide roller 43 which is rotatable about a rotational axis A, the guide roller 43 being provided on a tensioning sensing member 44 which is mounted on the body member 40 for rotation about a further axis B which is generally parallel but spaced from the rotational axis A, against the force of a restoring spring (not seen) as tension in the ribbon 15 increases. An indicating part 45 of the sensing member 44 thus moves relative to the body member 40, which movement is sensed by a displacement sensor such as a Hall effect sensor which is provided at a second side of the body member 40 opposite the one side on which the sensing member 44 is mounted.

The displacement sensor provides input to the controller 32 for the purposes of controlling the ribbon 15 tension along the ribbon feed path, by controlling the take-up spool drive motor 30 and the storage spool drive motor or ribbon drive roller, whichever is provided.

A third ribbon guide 50 is of identical or similar construction to the ribbon sensing mechanism, but is not used for providing input to the controller 32, and a fourth ribbon guide 51 which is a simple guide roller, is provided adjacent the take-up spool 28.

Thus with this geometry, the storage and take-up spools 25, 28 are provided between a first pair of the ribbon guides i.e. the first and fourth ribbon guides 41, 51, whilst the printing station 11 is provided between the other pair of *.* 20 ribbon guides i.e. the second 42 and third 50 ribbon guides. S.. S a a *SS.

Ribbon on the storage spool 25 is in figure 1, inked on a radially inner surface I 5a of the ribbon 15 when it is wound on the storage spool 25 and thus is said to be radially internally wound. As it is required to present the inked surface * 25 1 5a to the substrate at the printing station 11, the storage spool 25 is mounted such upon unwinding the ribbon 15, the storage spool 25 undergoes a clockwise rotation as seen in figure 1 of the drawings, as the ribbon 15 passes to the first ribbon guide 41, so that the inked surface 15a is presented outwardly.

The take-up spool 28 similarly is rotated clockwise to take-up used ribbon 15, winding the ribbon 15 so that the used inked surface 15a is radially internally wound as the ribbon 15 is received from the fourth ribbon guide 51.

Thus for use of the printing apparatus 10 with ribbon 15 with a radially internally inked surface 15a, the ribbon 15 is threaded in a first ribbon feed path as seen in figure 1, about the ribbon guides.

In figure 2 however, where the same printing apparatus 10 is shown, the ribbon 15 is threaded about the ribbon guides 41, 43, 51, 51 in an alternative second ribbon feed path, and the ribbon 15 is provided on a storage spool 25 in which the ribbon 15 has an inked radially externally wound surface I 5b.

In this operating mode, to unwind the ribbon 15 from the storage spool 25, the storage spool 25 needs to rotate anti-clockwise, and the used ribbon take-up spool 28 needs similarly to rotate anti-clockwise to wind the used ribbon 15 onto the take-up spool with the used inked ribbon surface 15b wound radially externally.

: 20 To enable the same printing apparatus 10 to be used for either radially

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externally or radially internally inked ribbon 15, the ribbon 15 must be appropriately threaded about the ribbon guides 41, 42, 50 and 51, and the appropriate operating mode selected, by providing input to the controller 32.

Whereas the inked radially internally or radially externally wound ribbon operating mode may be selected by operation of a simple mechanical switch, in this example, the printing apparatus 10 is of the kind in which the controller 32 is programmed with parameters relating to the printing to be carried out, and in accordance with the invention, one parameter to be selected is the operating mode depending upon whether the ribbon 15 is inked on its radially internally or externally wound surface I 5a, I 5b.

An input device is shown at 60 in figure 1, which is plugged into and thus operatively connected to the controller 32, the input device 60 including a keypad 61 and display 62 usable for programming the controller 32 with printing parameters.

The input device 60 illustrated is a hand held unit, which may be permanently connected to the controller 32, or may be temporarily connectable to the controller 32 for programming the controller, and is then removable therefrom e.g. for use in programming the controller of another printing apparatus 10.

However a non-hand-held input device, even a wireless device, may be used to program the controller 32 is desired.

The input device 60 is used to program the controller 32 either to cause the take-up spool drive motor 30 (and storage spool 25 drive motor where provided) to rotate clockwise where the ribbon 15 used is inked on its radially internally wound surface I 5a, as in figure 1, or to rotate anti-clockwise where the ribbon 15 used is inked on its radially externally surface 15b, as in figure 2.

Various modifications in addition to those already noted may be made without

IS

departing from the scope of the present invention. For example, the provision of a body member 40 to mount the various printer apparatus 10 components and/or the particular configuration of the body member 40 illustrated is only exemplary, although the generally rectangular geometrical arrangement readily lends itself to a printing apparatus 10 capable of handling both ribbon which is inked on its radially internally wound surface I 5a, or which is inked on its radially externally wound surface I 5b.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof. S. * S * U.. S... * S 5US * U. * U S U.. S U..

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Claims

CLAIMS

1. A method of printing utilising a printing apparatus including at a printing station, a print head having an array of printing elements which are selectively energisable, to remove pixels of ink from an inked carrier ribbon to print an image on a substrate, the apparatus further including a storage spool for ribbon to be used in printing and a take-up spool for used ribbon and a ribbon feed path including a plurality of ribbon guides for the ribbon between the storage and take-up spools, through the printing station where the ribbon is interposed between the print head and the substrate, and there being a drive motor for driving at least the take-up spool for taking up used ribbon from the printing station in a ribbon feed direction, and the method including, where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on the radially internally wound surface of the ribbon, threading the ribbon in a first ribbon path around the ribbon guides, and where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on the radially externally wound surface of the ribbon, threading the ribbon in a second ribbon path around the ribbon guides, and selecting a first or second operating mode, and when the first rrode of operation is selected and the ribbon is inked *" 20 on its radially externally wound surface, operating the drive motor to rotate the S...

ribbon take-up spool in a first sense of rotation, and when the second mode of operation is selected and the ribbon is inked on its radially externally wound surface, operating the drive motor to rotate the ribbon take-up spool in a second sense of rotation opposite to the first sense of rotation.

I

III.., a.

2. A method according to claim I wherein the printing apparatus includes a drive motor for the storage spool, and upon selection of the first operating mode, the storage spool drive motor is operated to rotate the storage spool in the first sense of rotation and where the second operating mode is selected the storage spool drive motor is operated to rotate the storage spool in the second sense of rotation.

3. A method according to claim 1 or claim 2 wherein the printing apparatus includes a ribbon tension sensing mechanism which senses the ribbon tension along the ribbon feed path, the ribbon tension sensing mechanism in use, providing input to a controller which controls ribbon tension around the ribbon feed path, by varying the rotational speed of the take-up spool motor and where provided, the storage spool drive motor, to maintain ribbon tension in the ribbon feed path between acceptable limits.

4. A method according to any one of claims I to 3 wherein the printing apparatus includes an encoded ribbon guide roller which senses ribbon feed speed, and the encoded ribbon guide roller in use, providing input to a controller which controls ribbon speed around the ribbon feed path, by varying the rotational speed of the take-up spool motor and where provided, the storage spool drive motor.

5. A method according to any one of the preceding claims wherein the printing apparatus includes a substantially rectangular body member mounting the storage and take-up spools and the print head, the body member including *.* 20 a ribbon guide generally at each corner, with the storage and take-up spools being provided between a first pair of the ribbon guides and the printing station being provided between the other, second, pair of ribbon guides.

6. A method according to any one of the preceding claims wherein the : 25 method includes selecting the appropriate operational mode for handling inked radially internally or externally wound ribbon, by operating a simple.switch which provides input to the controller.

7. A method according to any one of claims I to 5 wherein the method includes selecting the appropriate operational mode for handling inked radially internally or externally wound ribbon by programming a controller using an input device.

8. A method according to claim 7 wherein the input device is a keypad which is permanently or temporarily connected to the controller of the printing apparatus for programming the controller.

9. A method of printing substantially as hereinbefore described with reference to the accompanying drawings.

10. A printing apparatus including at a printing station, a print head having an array of printing elements which are selectively energisable, to remove pixels of ink from an inked carrier ribbon to print an image on a substrate, the apparatus further including a storage spool for ribbon to be used in printing and a take-up spool for used ribbon, and a ribbon feed path including a plurality of ribbon guides for the ribbon between the storage and take-up spools, through the printing station where the ribbon is interposed between the print head and the substrate, and there being a drive motor for driving at least the take-up spool for taking up used ribbon from the printing station in a ribbon ".. 20 feed direction, and a mode selection device for selecting a first operating S...

mode where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on a radially internally wound surface of the ribbon, and the : * ribbon is threaded in a first ribbon path around the ribbon guides, whereby in use, the drive motor is operated to rotate the ribbon take-up spool in a first :: 25 sense of rotation, and for selecting a second operating mode where the inked carrier ribbon is provided as a storage spool in which the ribbon is inked on the radially externally wound surface of the ribbon, and the ribbon is threaded in a second ribbon path around the ribbon guides, whereby in use, the drive motor is operated to rotate the ribbon take-up spool in a second sense of rotation opposite to the first sense of rotation.

11. A printing apparatus substantially as hereinbefore described with reference to and/or as shown in the accompanying drawings.

12. Any novel feature of novel combination of features described herein and/or as shown in the accompanying drawings. S. * S * IS. *55 * * S **S. * .5 * . . S.. S S..

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