GB2434563A

GB2434563A - Marking system with integrated linearity synchronisation

Info

Publication number: GB2434563A
Application number: GB0425986A
Authority: GB
Inventors: Gary David Stamp; Peter Richard Lisher; Ashley Glenister
Original assignee: QUILL CODING SOLUTIONS Ltd
Current assignee: QUILL CODING SOLUTIONS LIMITED
Priority date: 2004-11-26
Filing date: 2004-11-26
Publication date: 2007-08-01
Also published as: GB0425986D0

Abstract

The system applies marks (i.e. human or machine readable) by a marking device 200 and uses an internal synchronisation system to ensure the quality of the mark is optimum whilst allowing the use of less expensive, wider tolerance components. An encoder 201 monitors internal marking device movement which is analysed by the common control system 208 to synchronise individual lines of the mark being printed thus compensating for mechanical variations of the marking device 200 . Critically, the synchronisation process allows printing to occur earlier within the marking cycle leading to a significant increase in productivity. The marking system enclosure is mounted on a stage 207 and positioned to produce a mark 206 upon items 204 as they are placed 205 at the marking device.

Description

MARKING SYSTEM WiTH INTEGRATED LINEARITY SYNCHRONISATION.

Background

The present invention relates to field of marking, and particularly but not exclusively, to machine and human readable codes found on food and pharmaceutical packaging including but not limited to, expiry dates and production batch codes.

Within industry in general, there is a requirement to mark products and product packaging with unique identifying codes and information relating to contents, expiry dates and production codes. It is also important that producing such marks does not slow the capacity of the production line.

In the European Union, Directive N 2000/13/EC on labelling, identifies the rules put in place on the labelling of foodstuffs to enable, amongst other things, European consumers to get comprehensive information on the contents and the composition of food products. Further legislation governs the labelling and marking of pharmaceutical packaging to guarantee product integrity and trace ability.

It is critical that products contain the appropriate mark to identify, but not exclusively, content and expiry dates. This is particularly important with pharmaceuticals but also perishable products, which are required to be traced back to origin of manufacture. In some instances supplying a poorly or inaccurately marked package is likely to incur a fine and possible suspension from supplying such future product.

Prior art marking methods include thermal transfer, laser and inkjet. The mark must be legible, accurate, indelible and machine- readable where appropriate. Many factors affect the quality of the mark and include the accurate positioning of lines and spaces, which together form machine-readable barcodes and character construction for human readable codes.

Prior art validation systems, deploying image capture techniques, are added to the production line and operate separately and independently to the marking device to check that products have been correctly marked. The complexity of computer algorithms to analyse human and machine-readable marks, requires a preliminary set up process where the image capture and validation device must first determine character parameters to recognise specific marks.

Subsequent printed marks must not greatly deviate from those initially recognised and stored by the validation system.

What is required is an integrated marking system that uses low cost and low tolerance components where printer instability is compensated and an appropriate mark of the highest quality with reproducible results is produced so that subsequently the marks are capable of tolerating the maximum amount of damage and still remain readable.

Statement of invention

Specific implementations of the present invention aim to provide a marking system in which a product is marked and employs an integrated linearity synchronisation system to maintain high quality character shapes, including but not exclusively machine readable barcodes, reducing the need for high tolerance and expensive system components.

In the best mode implementation, marking and linearity synchronisation is carried out under the control of a single machine containing the marking device, a spatial encoder device and a data control system.

In the best mode, a marking device, a spatial encoder device and a data control system operates to perform: integrated marking, synchronising printed data to compensate for irregular print head movement to deliver a consistent spatially accurate mark.

The marking and linear synchronisation is carried out under the control of a common control system. A user interface may be provided, enabling an operator to monitor stages of marking and synchronisation activity to set quality levels below which, items marked would automatically be rejected.

According to a first aspect of the present invention, there is provided an integrated component marking system comprising: a marking device for applying a mark directly to packaging; and a spatial encoder device for accurately measuring movement within the marking device.

a common control system for controlling said marking device and said spatial device and said data applied to the marking device.

According to a second aspect of the present invention, there is provided an integrated method of applying a mark to packaging, and compensating for mechanical tolerance within the marking device, said method comprising: applying said mark to at least one item of packaging whilst capturing spatial movement and ensuring said mark is within a specified tolerance, wherein said processes of applying said mark and capturing said movement, are carried out by a common control system.

According to a third aspect of the present invention, there is provided an integrated method of applying a mark to packaging, and applying compensation to subsequent marks, said method comprising: Delivering each printed line comprising said mark, to at least one packaged item then capturing spatial movement of said applied marking device and analysing said captured spatial detail to compensate and synchronise subsequent printed lines to ensure verify said mark is within a specified tolerance.

According to a fourth aspect of the present invention, there is provided a method of monitoring the stability of the manufacturing process said method comprising: Delivering each printed line comprising said mark, to at least one packaged item then capturing spatial movement of said applied marking device and analysing said captured spatial detail to compensate and synchronise subsequent printed lines to ensure verify said mark is within a specified tolerance.

According to a fifth aspect of the present invention, there is provided a method of monitoring a maintenance condition of the production line to which the marking device is fitted, said method comprising: Delivering each printed line comprising said mark, to at least one packaged item then capturing spatial movement of said applied marking device and analysing said captured spatial detail to compensate and synchronise subsequent printed lines to ensure verify said mark is within a specified tolerance to determine the operational stability of the production line and resulting trends indicating deterioration of performance.

The invention includes an interface display for operating a marking, verification and compensation apparatus for applying at least one mark to at least one packaged item and for monitoring levels of synchronisation for said mark, said interface comprising; A pass/warning/fail indicator for indicating a result of the synchronisation process and a data display for displaying marking data, subject of said applied mark and a stable/warning/unstable indicator for indicating the condition of the production line.

The invention includes an interface display for configuration of marking and synchronisation apparatus and diagnostic set up for spatial encoder device.

Further features of the invention are as recited in the claims herein. The scope of the invention is limited only by the scope of the claims herein.

Advantages In the food and pharmaceutical industries it is essential that products be correctly marked to indicate content, manufacture audit trail and expiry date. Manual checking of each package is not practical on high speed manufacturing lines. Present optical validation systems in use are added to the process but are very sensitive to the quality and stability of the mark.

Expensive, high tolerance components are necessary to produce accurate marks, particularly for computer readable barcodes and vision validation systems, and still satisfy the need for high productivity. More critically, system component set-up and wear degrades the quality of the printed mark over time and the marking device must be frequently maintained.

The invention described herein uses considerably cheaper and lower tolerance components without loss of print quality and also significantly improves productivity.

In addition, the invention reduces the need for such frequent maintenance.

Introduction to drawings

For a better understanding of the invention and to show how the same may be carried out into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to accompanying drawings which: Figure 1 Illustrates schematically a prior art food label mark, comprising a barcode with human readable characters.

Figure 2 Illustrates schematically in perspective view a marking system with integrated spatial synchronisation according to a first specific implementation of the present invention.

Figure 3 Illustrates schematically a surface to be marked and a prior art marking machine, comprising a carriage with print head and fixed guide bar.

Figure 4 Illustrates schematically a prior art marking machine, comprising a print head and carriage, guide bar and a surface to be marked which contains a plurality of deposited printed pixels.

Figure 5 Illustrates schematically a prior art marking machine, comprising a print head and carriage, guide bar and a surface to be marked which contains a plurality of deposited printed pixels and a graph depicting print head displacement verses velocity throughout the print cycle.

Figure 6 Illustrates schematically a prior art marking machine, comprising a print head and carriage, guide bar and a surface to be marked which contains a plurality of deposited printed pixels and a graph depicting print head displacement verses velocity throughout a compressed print cycle.

Figure 7 Illustrates schematically a marking machine according to best implementation of the present invention, comprising a print head and carriage, and a surface to be marked which contains printed pixels, a graph depicting print head displacement verses velocity throughout a compressed print cycle and signals produced by a spatial encoder.

Figure 8 Illustrates schematically in perspective view a prior art marking machine prior to the marking operation, comprising a print head and carriage, a motor device and belt system, and a surface to be marked.

Figure 9 Illustrates schematically in perspective view a prior art marking machine subsequent to the marking operation, comprising a print head and carriage, a motor device and belt system, and a surface to be marked.

Figure 10 Illustrates schematically in perspective view a marking machine, prior to the marking operation, according to best implementation of the present invention, comprising a print head and carriage and spatial encoder, and a solenoid device and spatial encoder, and a surface to be marked.

Figure 11 Illustrates schematically in perspective view a marking machine, subsequent to the marking operation, according to best implementation of the present invention, comprising a print head and carriage and spatial encoder, and a solenoid device and spatial encoder, and a surface to be marked.

Detailed description

There will now be described by way of example the best mode contemplated by the inventors for carrying out the invention. In the following description numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details including but not limited to, methods that apply linear motion. In other instances, other well-known methods and structures have not been described in detail so as not to unnecessarily obscure the present invention.

Specific implementations according to the present invention provide for an integrated marking system with data synchronisation:-in particular applying human readable and computer readable marks with high spatial accuracy using low cost, low tolerance marking system components.

A package is delivered beneath the marking device and a signal passed to the marking system from the packaging system, requesting a mark to be printed. The marking system produces the mark, particularly but not exclusively, using a prior art inkjet printing process.

During the printing process, an encoder monitors the position of the print head and synchronises the application of data and control signals. The encoder compensates variations in acceleration and velocity such that data is only printed when the print head is in the correct position. This produces a highly accurate linearity of print whilst utilising low spec components.

Fluctuations between encoder signals are further used to indicate the stability of the production process aiding users to maximise manufacturing capacity and anticipate when maintenance will be required.

There will now be described in detail, a specific marking and synchronisation system and method of operation of the marking and synchronisation system and a marking -8.-and synchronisation method, according to a specific implementation of the present invention.

Referring to Figure 1. herein, there is Illustrated a prior art food label mark, comprising a barcode with human readable characters. The barcode is constructed from lines 1101 and spaces 1001 which are spatially accurately positioned 1021 to create specific characters which are recognised by an appropriate scanning system.

The prior art food label mark also contains human readable characters.

Referring to Figure 2. herein, there is illustrated schematically in perspective view a marking system with integrated spatial synchronisation according to a first specific implementation of the present invention. The machine comprises a mounting 12071 supporting the single print head 203! comprising: marking device 2001 and encoder device 12011. The marking control system 12081 also contains the user interface visual display unit with associated touch screen 12021. The print head 12031 is mounted above the items to be marked 12041. Each item to be marked is presented under the head by a conveyor 12051 and held stationary whilst the full mark is applied 12061 to the item j204j.

Referring to Figure 3. herein, there is illustrated schematically a marking device composing a travelling carriage 13011 which traverses back and forth along a fixed bar 303!. An inkjet print head 300! which positions a plurality of jet elements (pixels) arranged across the print head and which are rapidly switched to generate drops of ink pigment which bond to the substrate 13021 being printed upon.

Referring to Figure 4. herein, there is illustrated schematically a marking device composing a travelling carriage 401! upon which is placed An inkjet print head 14001 where the assembly traverses along a fixed bar 14031. Under the control of a central control system, the carriage assembly is accelerated from its home position 1406! along the fixed bar 403! and then maintained at a stable velocity. The central control system controls the print head to deliver pixels 1405! thus forming the total image 4041 to be printed upon the substrate 14021.

Referring to Figure 5. herein, there is illustrated schematically a marking device composing a travelling carriage 15011 upon which is placed An inkjet print head 15001 where the assembly traverses along a fixed bar 5031. Under the control of a central control system, the carriage assembly is accelerated from its home position 15061 along the fixed bar 503! and then maintained at a stable velocity 15081. The central control system controls the print head to deliver pixels 15051 thus forming the total image 504) to be printed upon the substrate 502!. The carriage assembly requires a settling time before the first line of the image is printed 15091 to allow for velocity variations 15101 due to the effect of inertia caused by the rapid acceleration of the carriage assembly 15011. When the complete image has been printed 15071 the carriage assembly is decelerated 15111 then returned to home 15061 ready for another print operation.

Referring to Figure 6. herein, there is illustrated schematically a marking device which reduces the print cycle time but produces unacceptable print quality. The marking device composes a travelling carriage 16011 upon which is placed an inkjet print head 1600! where the assembly traverses along a fixed bar 16031. Under the control of a central control system, the carriage assembly is accelerated from its home position 6061 along the fixed bar 16031. The central control system controls the print head to deliver pixels 16041 to be printed upon the substrate 16021 without waiting for a settling time 1610) or achieving a stable velocity 16081. The changes in velocity are not monitored by the control system and lines of image are poorly spaced and of varying sizes 16051 1612!.

By example, the poor spatial quality of the printed image will result in barcodes being unreadable by electronic scanners and human rcadable characters being rejected by on-line image verification systems.

Referring to Figure 7. herein, there is illustrated schematically a marking device According to a first aspect of the present invention which reduces the print cycle time and produces high quality print. The marking device composes a travelling carriage 17011 upon which is placed an inkjet print head 17001 where the assembly traverses along a fixed bar 703). Under the control of a central control system, the carriage assembly is accelerated from its home position 17061 along the fixed bar 7031. The central control system controls the print head to deliver a line of image 7041 to be printed upon the substrate 7021 without waiting for a settling time 7101 or achieving a stable velocity 17081. An encoder monitors the carriage assembly 17011 displacement as the carriage traverses the length of the fixed bar 17031 and produces a signal 17131 coincident to the start position of each image line to be printed. The central control system uses the encoder signal to synchronise the printing of each line of image irrespective of carriage velocity 17081. Lines of printed image remain evenly spaced and of equal size 1705117121.

By example, with a reduced print cycle time, the carriage assembly requires less time to complete the print operation 17061 consequently increasing overall productivity of the host packaging machine.

Referring to Figure 8. herein, there is illustrated schematically in perspective view a Prior art Marking device comprising: an inkjet print head 18001, fitted to a carriage 18011 which positions a plurality of jet elements (pixels) arranged across the print head at a pitch, but not exclusively, in excess of 300dpi and which are rapidly switched to generate droplets of ink. Items to be marked 18021 are positioned beneath the print head, a synchronised signal from the host packaging line requests a marking operation. The marking device control system employs a motor 8051 and pulley belt 18061 to accelerate the carnage assembly 18011 comprising pulley belt connection 18041 and the print head 8001, along the guide bars 18031.

Referring to Figure 9. herein, there is illustrated schematically in perspective view a Prior art Marking device comprising: an inkjet print head 19001, carriage assembly 19011 and motor device J905j. Items to be marked 19021 are positioned beneath the print head, a synchronised signal from the host packaging line requests a marking operation. The marking device control system employs a motor 19051 and pulley belt 19061 to accelerate the carriage assembly 19011 along the guide bars 18031. When the carriage has stabilised at a velocity, the marking device control system prints individual lines of the image upon the substrate 19021. Once the full image has been -11 -printed the carriage assembly is decelerated and reversed back to its original position ready to repeat the printing process.

Referring to Figure 10. herein, there is illustrated schematically a marking device according to a first aspect of the present invention comprising: an inkjet print head 10001, fitted to a carriage 110011 which positions a plurality of jet elements (pixels) arranged across the print head at a pitch, but not exclusively, in excess of 300dpi and which are rapidly switched to generate droplets of ink. Items to be marked 10021 are positioned beneath the print head, a synchronised signal from the host packaging line requests a marking operation. The marking device control system employs, particularly but not exclusively, an electrical solenoid 110051 which attracts the rod 110061. The rod contains regular position marks 1006! which are monitored by an encoder 110071. The rod 110061 is coupled to the carriage assembly 110041 and when the solenoid 1005! is energised by the marking device control system, the carriage assembly accelerates towards the solenoid 11005.

Referring to Figure 11. herein, there is illustrated schematically a marking device according to a first aspect of the present invention comprising: an inkjet print head 111001 fitted to a carriage 111011, electrical solenoid 111051 and an encoder 1107!.

Items to be marked 11002! are positioned beneath the print head, a synchronised signal from the host packaging line requests a marking operation. The marking device control system employs an electrical solenoid (1005! which attracts the rod 110061. The rod contains regular position marks 110061 which are monitored by an encoder 110071.

The rod 110061 is coupled to the carriage assembly 110041 and when the solenoid 110051 is energised by the marking device control system, the carriage assembly accelerates towards the solenoid 10051.

The marking device control system prints individual lines of the image upon the substrate (11021 synchronised to the marks on the rod 111061 detected by the encoder 11107!. Once the full image has been printed the carriage assembly is decelerated and the solenoid polarity reversed to return the carriage back to its original position ready to repeat the printing process.

Claims

V

Claims Claim 1. An integrated packaging marking system with instantaneous spatial synchronisation comprising: a marking device for applying a mark to products or their packaging, an encoder device for monitoring marking system operation, a control system for controlling said marking device, said encoder device.

Claim
2. The system as claimed in claim 1, wherein said common control system comprises a user interface.

Claim
3. The system as claimed in any one of the preceding claims, wherein said mark comprises machine readable or human readable marks or a combination of machine readable and human readable marks.

Claim
4. Fhe system as claimed in any one of the preceding claims, wherein said quality of printed mark is specified by the packaging rules for the items being marked.

Claim
5. The system as claimed in any one of the preceding claims, wherein, said packaged undergoes a marking operation.

Claim
6. The operation as described in claim 5, wherein the synchronisation system extends the marking device useful operating life by accommodating poor mechanical stability whilst still producing a mark within the packaging rules.

Claim
7. The operation as described in claim 5, wherein the synchronisation operation adjusts the mark spatial linearity to maintain a mark within the packaging rules.

Claim
8. The operation as described in claim 5, wherein the content of the printed mark may differ between one mark and another.

Claim
9. The system as claimed in any one of the preceding claims, further comprising: a visual display device, said visual display device configured for displaying at least one display interface.

Claim
10. The system as claimed in any one of the preceding claims, wherein, said marking device and encoder device are housed within a single housing or separated into marking device and encoder device under the control of a common control system.

Claim
11. An integrated method of applying a mark to a package and compensating for internal parts with wide tolerance of operation whilst producing a mark within the packaging rules.

Claim
12. An integrated method of applying a mark to a package and utilising all of the print cycle to deliver the mark thus increasing throughput and productivity of the host packaging machine.

Claim
13. The method as claimed in claim 12, further comprising: a common user interface.

Claim
14. An integrated method of applying a mark to a package and synchronising said mark said method comprising: inputting a set of data to create at least one mark and applying said mark to at least one package or packaging; and capturing a spatial signal of said marking process, syncbronising the printing process to the spatial signal ensuring said mark is within packaging rules.

Claim
15. The method as claimed in claim 14, further comprising: Recording and analysing consecutive compensation parameters to establish the stability of the production process and likely probability of rejected marks.

Claim 16 The method as claimed in claim 15, further comprising a common user interface and display providing a indication of system performance.