Patent Application
20210138795
This disclosure relates to card processing systems that perform drop-on-demand (DOD) printing on plastic cards including, but not limited to, financial (e.g., credit, debit, or the like) cards, driver's licenses, national identification cards, business identification cards, gift cards, and other plastic cards.
In DOD printing, ink is ejected from one or more nozzles of a print head by electrically energizing select ones of the nozzles from which the ink is to be ejected. DOD printing on plastic cards in a card processing system presents unique challenges. The printing on the plastic card must be durable and long-lasting, as well as being of very high quality. In addition, the printing can vary from monochromatic using a single color to multi-color using multiple colors such as cyan, magenta, yellow, black and white ink. Further, the card throughput (i.e. the number of cards printed per unit of time) is an important factor in a card processing system that employs DOD printing and efforts are made to maximize the card throughput. Moreover, the printing that occurs on the plastic cards can and often does vary from card to card.
DOD ink delivery systems and methods are described herein that are used in DOD card printing systems of card processing systems for supplying ink for DOD printing on plastic cards of the type that bear personalized data unique to the intended cardholder and/or which bear other card information. Examples of plastic cards can include, but are not limited to, financial (e.g., credit, debit, or the like) cards, driver's licenses, national identification cards, business identification cards, gift cards, and other plastic cards.
In one embodiment described herein, the DOD ink delivery system is configured to recirculate the ink without using a recirculation tank separate from an ink supply. In one embodiment, the ink supply can be a vessel that the ink is purchased/supplied in and is intended to be disposed of after use. In another embodiment, the ink supply can be any form of single use vessel that is intended to be disposed of after use. A recirculation tank or bulk tank is a fixed component in the system that is designed to be filled with ink from a source of ink, and the tank is not easily removable and is not intended to be discarded after use when the ink runs out. Recirculation is useful for inks that need to be recirculated to improve the resulting performance of the ink when applied to a plastic card. The ink could be an ink with a particulate material in the ink, with the recirculation keeping the particulate adequately dispersed in the ink. Examples of inks with a particulate material include, but are not limited to, white ink and what in the card printing industry are referred to as spot colors that include gold, silver, red colored inks. The ink could also be an ink (with or without particulate material, and possibly either a spot color or not a spot color) that is recirculated in order to remove gas from the ink.
The card processing systems described herein can be any card processing systems that can process plastic cards by printing on the cards using a DOD card printing system having one or more DOD print heads, for example piezo-electric print heads, in combination with one or more of: reading data from and/or writing data to a magnetic stripe on the cards, programming an integrated circuit chip on the cards, emboss characters on the cards, indenting characters on the cards, laminating the cards, using a laser that performs laser processing such as laser marking on the cards, applying a topcoat to a portion of or the entire surface of the cards, checking the quality of personalization/processing applied to the cards, applying a security feature such as a holographic foil patch to the cards, and other card processing operations.
The DOD card printing system used in the card processing system can have a single DOD print head or a plurality of DOD print heads. The DOD print heads can be piezo-electric print heads. The DOD card printing system can perform monochromatic or multi-color printing. In one example of multi-color printing, five DOD print heads, each of which has a plurality of nozzles, can be provided. Each print head can be designated to print a specific color ink, such as cyan, magenta, yellow, black and white (CMYKW). The DOD card printing system can print using any suitable ink (or other material) used in DOD printing and that is suitable for use on the types of plastic cards described herein. For example, the ink can be an ultraviolet (UV) radiation curable ink.
In one embodiment, a drop-on-demand card printing system can include a drop-on-demand print head having an ink inlet and an ink outlet, and an ink delivery system connected to the drop-on-demand print head. The ink delivery system can include a first ink header tank fluidly connected to the ink inlet and a second ink header tank fluidly connected to the ink outlet, and an ink recirculation system defining an ink recirculation path that is configured to permit ink to be recirculated through the first ink header tank and the second ink header tank. The ink recirculation system is devoid of an ink supply tank whereby the recirculating ink is not directed into an ink supply tank after leaving the second ink header tank and before entering the first ink header tank. The drop-on-demand card printing system can also include a vacuum system that is fluidly connected to the first and second ink header tanks and that applies a vacuum to the drop-on-demand print head.
In another embodiment, a method of operating a drop-on-demand card printing system of a card processing system is described. The drop-on-demand card printing system includes an ink delivery system connected to a drop-on-demand print head, where the ink delivery system has a first ink header tank fluidly connected to the ink inlet and a second ink header tank fluidly connected to the ink outlet. The method includes recirculating ink through the first ink header tank and the second ink header tank via the drop-on-demand print head using an ink recirculation system that defines an ink recirculation path that is configured to permit the ink to be recirculated through the first ink header tank and the second ink header tank that is devoid of an ink supply tank in the ink recirculation path whereby the recirculating ink is not directed into an ink supply tank after leaving the second ink header tank and before entering the first ink header tank.
In still another embodiment, a method of operating a drop-on-demand card printing system of a card processing system is described. The drop-on-demand card printing system can include an ink delivery system connected to a drop-on-demand print head, where the ink delivery system has a first ink header tank fluidly connected to the ink inlet, a second ink header tank fluidly connected to the ink outlet, and an ink supply bottle. The method includes pumping ink directly from the ink supply bottle into the first ink header tank when the first ink header tank needs to be supplied with ink, and pumping ink from the second ink header tank directly into the ink supply bottle thereby causing mixing of ink within the ink supply bottle when ink needs to be removed from the second ink header tank.
In still another embodiment, a method of operating a drop-on-demand card printing system of a card processing system is described. The drop-on-demand card printing system can include an ink delivery system connected to a drop-on-demand print head, where the ink delivery system has a first ink header tank fluidly connected to the ink inlet, a second ink header tank fluidly connected to the ink outlet, and a mounting location for mounting an ink supply bottle. The method includes pumping ink directly from the second ink header tank back into the first ink header tank when the ink supply bottle is not present at the mounting location and ink needs to be removed from the second ink header tank.
The cards to be processed within the card processing system 10 include, but are not limited to, plastic cards which bear personalized data unique to the intended cardholder and/or which bear other card information. Examples of plastic cards can include, but are not limited to, financial (e.g., credit, debit, or the like) cards, driver's licenses, national identification cards, business identification cards, gift cards, and other plastic cards.
In some embodiments, the DOD card printing systems 12 described herein can be used to print on substrates other than plastic cards, such as paper substrates, in which case the DOD card printing systems 12 can be referred to as DOD printing systems.
In the system 10 illustrated in
Operation of the various systems 12, 14, 16, 18, 20, 22 is controlled by one or more controllers 24. Alternatively, each one of the system 12, 14, 16, 18, 20, 22, or select ones of the systems 12, 14, 16, 18, 20, 22 can have its own dedicated controller.
The cards can be transported through the card processing system 10 using any suitable mechanical card transport mechanism(s) that are well known in the art of card handling within card processing systems 10. Examples of card transport mechanisms that could be used are known in the art and include, but are not limited to, transport rollers, transport belts (with tabs and/or without tabs), vacuum transport mechanisms, transport carriages, and the like and combinations thereof. Card transport mechanisms are well known in the art including those disclosed in U.S. Pat. Nos. 6,902,107, 5,837,991, 6,131,817, and 4,995,501 and U.S. Published Application No. 2007/0187870, each of which is incorporated herein by reference in its entirety. A person of ordinary skill in the art would readily understand the type(s) of card transport mechanisms that could be used, as well as the construction and operation of such card transport mechanisms.
The card processing system 10 illustrated in
In
The system 10 may include additional card processing systems not illustrated in
Non-limiting examples of the DOD card printing system 12 are illustrated in
Each of the DOD card printing systems 12 in
The printing performed by the DOD card printing system 12 can be monochromatic using a single color or multi-color using two or more colors. If multiple print heads are used, the print heads are arranged generally side-by-side to sequentially print onto a surface of a card as the card is transported past the print heads, for example underneath the print heads. The DOD print head(s) 30 can print using any suitable ink or coating (such as a varnish) used in DOD printing and that is suitable for use on the types of plastic cards described herein. For example, the ink can be a UV curable ink, a heat curable ink that can be cured by applying heat to the heat curable ink, or other ink or other materials that can be deposited by a DOD print head. An example of a DOD printer that prints using UV curable ink in a card printing system is the MX8100™ Card Issuance System available from Entrust Corporation of Shakopee, Minn. Each DOD print head 30 can print a specific color ink. The term fluid can be used to refer to any material, such as an ink or coating material, which can be applied to a card surface by the DOD print head 30.
In general, each DOD print head 30 includes a bottom surface that faces downward toward the plastic card to be printed on. A nozzle plate, through which ink is ejected, is provided on a portion of the bottom surface. The nozzle plate includes a plurality of openings therein, each opening being associated with a nozzle of the print head from which ink is ejected. Each DOD print head 30 can be a piezo-electric print head which requires electrical energy to energize the print head and dispense ink. The general mechanical construction and operation of piezo-electric print heads is well-known in the art.
Referring to
The print head 30 includes an inlet 40 connected to a supply side of the ink delivery system 32 and an outlet 42 connected to a recirculation side of the ink delivery system 32. The outlet 42 is distinct from the discharge nozzles from which ink is discharged during a printing operation and which are typically located at the bottom of the print head 30. On the supply side, the inlet 40 is fluidly connected to a first header tank 44 which contains an amount of the white ink and provides a constant supply of white ink to the print head 30. The supply side further includes a supply pump 48 that pumps the white ink into the header tank 44, a filter 50 between the supply pump 48 and the header tank 44 that filters the white ink, and a white ink supply bottle 52 that contains a supply of the white ink. The supply pump 48 is depicted as being a variable displacement pump. However, the supply pump 48 can have any construction that is suitable to allow the pump to perform the functions of the supply pump 48. In addition, a one-way check valve 46 is disposed between the supply pump 48 and the filter 50 that permits flow of the white ink toward the header tank 44 but prevents the flow of white ink back toward the supply pump 48. In some embodiments, the check-valve 46 and the supply pump 48 can be combined into a single component. Further, a solenoid valve 51 is provided between the filter 50 and the header tank 44 that can be used to drain the ink from the system via a waste collection system 90 discussed further below.
With continued reference to
A controller 60 is provided that is connected to the solenoid valve 51 to control the operation of the valve 51. The controller 60 (or a separate controller) can also be connected to the other controllable valves described herein. The controller 60 (or a separate controller) can also be connected to the pumps described herein to control the operation of the pumps. The controller 60 can be separate from, or the same as, the controller 24 in
An ink level sensor 62, such as a float sensor, can be provided in the header tank 54 for sensing the level of the ink in the header tank 54, with the sensor 62 providing ink level readings to the controller 60. In addition, an ink level sensor 64, such as a float sensor, can be provided in the header tank 44 for sensing the level of the ink in the header tank 44, with the sensor 64 providing ink level readings to the controller 60. In operation, one or more of the ink level readings in the header tanks 44, 54 can be used to determine when to recirculate ink. For example, the ink level readings from the ink level sensor 62 in the header tank 54 can be used to control the valve 51 and the operation of the pumps 48, 58 to determine when recirculation occurs.
The ink supply bottle 52 is not considered an ink supply tank as used throughout this description and the claims. Rather, the recirculation system and the recirculation path thereof is devoid of an ink supply tank. In one embodiment, the ink supply bottle can be a vessel that the ink is purchased/supplied in and is intended to be disposed of after use. In another embodiment, the ink supply bottle can be any form of single use vessel that is intended to be disposed of after use. An ink supply tank (also referred to as a recirculation tank or bulk tank) is a fixed component in a system that is designed to be filled with ink from a source of ink, and the tank is not easily removable and is not intended to be discarded after use when the ink runs out.
In the embodiment illustrated in
When the ink supply bottle 52 is not present, the ink is recirculated from the header tank 54 to the header tank 44. In particular, when the ink supply bottle 52 is removed, the quick-disconnect fluid fitting 53 is closed, and the recirculating ink flows from the return pump 58 to the supply pump 48 and from there into the header tank 44. Either one of the pumps 48, 58, or both of the pumps 48, 58 operating simultaneously, can be used to pump the recirculating ink from the header tank 54 to the header tank 44. The pumps 48, 58 can be configured as “free-flow” pumps that are configured to permit flow of the ink through the pumps 48, 58 when the pumps are in their off-state.
In the system 12 illustrated in
Returning to
A vacuum line 74 extends between the header tank 44 and the header tank 54, and a valve 82, such as a solenoid valve, is provided in the vacuum line 74. The valve 82 is used to isolate the header tank 54 from the vacuum system 34, which is required during certain maintenance routines such as during an auto fill, auto drain, purge, and the like. Further information on auto fill, auto drain, purge, and other maintenance routines are disclosed in U.S. Published Application No. 2019/0344565, and U.S. Published Application No. 2020/0039228, each of which are incorporated herein by reference in their entirety.
A waste collection system 90 is connected to the cap tray 36 to collect ink that may be discharged into the cap tray 36. The waste collection system 90 includes a waste manifold 92 that is fluidly connected to the cap tray 36 via a fluid line, and a waste pump 94 is provided in the fluid line that pumps waste ink from the cap tray 36 into the manifold 92. The waste collection system 90 further includes a system drain line 100 that extends from the valve 51 to the waste manifold 92. A system drain pump 102 is provided in the drain line 100. The pump 102 can be used to drain the entire ink system including, but not limited to, the print head 30, the header tanks 44, 54, the filter 50, and the supply bottle 52. The pump 58 can be run simultaneously as the pump 102 (but at a lesser flow rate) in order to drain the system.
In addition, the waste collection system 90 can include a waste collection container 96 into which waste ink from the waste manifold 92 can be collected. The waste collection container 96 can be connected to the system using a quick connect fitting to simplify installation and removal of the container 96. However, one consequence of this type of connection is if the user fails to install the container 96 into the quick connect fitting, there is potential to build pressure. To address this, a pressure switch 98 is provided which detects a build-up of pressure resulting from forgetting to connect the waste collection container 96, where the pressure switch 98 will send a signal to the controller 60 once a certain pressure is reached to warn the user of the pressure increase and/or to warn the user to install the waste collection container 96.
In operation of the system 12 in
When the ink supply bottle 52 is removed, for example by a user while installing a new ink supply bottle, a deadhead is created where the quick disconnect fluid fitting is suddenly closed. In this situation, if the return pump 58 is operated, the pressure of the returning ink is sufficient to overcome the check valve 46 and a “local” recirculation is achieved by recirculating the ink through the system, for example from the header tank 54 to the header tank 44, and from the header tank 44 to the header tank 54 via the print head 30. This can be referred to as local mixing or out-of-bottle mixing.
In the case of local recirculation when the supply bottle 52 is not present, the ink must be recirculated directly from the header tank 54 into the header tank 44. Therefore, the header tank 44 must be configured to accommodate the recirculating ink from the header tank 54 even if the ink level sensor 64 indicates that the header tank 44 is full. In the example illustrated in
In some embodiments, the ink supply bottle 52 can be provided with a radio frequency identification (RFID) element. The RFID element can have data stored thereon, such as an estimate of the amount of ink remaining in the supply bottle 52. The ink remaining data can be updated during use as ink is supplied from or returned back into the supply bottle 52. Other data that can be stored on the RFID element can include, but is not limited to, the type of ink, the color of the ink, the manufacturer of the ink, a “date of birth” of the ink indicating when the ink was created and/or first introduced into the bottle 52, suggested operating parameters of the print head 30 for the specific ink in the bottle 52, and the like. Data can be read from and/or written to the RFID element using a suitable read/write device in the card processing system 10 or in the card printing system 12.
In one embodiment, the RFID element on the supply bottle 52 can be used to control the return pump 58. For example, the RFID element can be used to control the speed of the return pump 58 based on the estimated amount of ink that remains in the supply bottle 52. When the amount of remaining ink is lower, the speed of the return pump 58 can be reduced since the recirculating ink being returned back into the supply bottle 52 does not need to be returned with as much force in order to achieve adequate mixing. In contrast, when the amount of remaining ink is higher, the speed of the return pump 58 is increased since the recirculating ink being returned back into the supply bottle 52 needs to be returned with higher force in order to achieve adequate mixing.
In particular, referring to
The system 12 in
Therefore, as illustrated in
The system 12 in
The examples disclosed in this application are to be considered in all respects as illustrative and not limitative. The scope of the invention is indicated by the appended claims rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.
| Number | Date | Country | |
|---|---|---|---|
| 62933605 | Nov 2019 | US |
