The present invention relates generally to ribbon spooling systems, and more specifically to systems and methods for controlling tension in a ribbon spooling assembly.
Ribbon spooling systems are used for a wide variety of applications, including, for example, credit card printing systems and other systems. In particular applications, it may be beneficial for the ribbon spooling systems to use more than one ribbon spool mounted on a payout core/reel that dispenses the ribbons to a takeup core/reel. However, a number of challenges are presented with the use of two or more ribbon spools. Differences in the initial diameter of the ribbons on the spools or in the thicknesses of the ribbon materials can cause problems in maintaining a constant tension in both ribbons due to unequal payout of ribbon materials. Such problems become more apparent when considering the cumulative effects of the differences in diameter and/or ribbon thickness. Ultimately, a conventional payout reel rotating both of the unequal ribbon spools will cause a lack of tension in one of the ribbons.
Proper ribbon tension in tape and ribbon spooling systems can be important. For example, in an impact printer with a moving print head having an inked ribbon suspended between the print head and a record medium (such as paper or card stock) by two guides (located on either side of the printer), the ribbon generally needs to be suspended at a proper constant tension. Insufficient ribbon tension may result in sloppy and inaccurate printing to the record medium and other printer malfunctions. Excessive ribbon tension, on the other hand, can cause stalling of the ribbon take-up spool, curling or improper winding of the ribbon onto the take-up spool, or breakage of the ribbon. As such, improved systems and methods for controlling tension in a ribbon spooling assembly would be beneficial.
Aspects of the invention relate to systems and methods for controlling tension in a ribbon spooling assembly. In one embodiment, the invention relates to a ribbon tension control assembly for maintaining substantially constant tension in a ribbon, the assembly including a payout core having a cylindrical shape, a first ribbon spool mounted on the payout core and attached thereto, a second ribbon spool mounted on the payout core, the second ribbon spool configured to move independent from the payout core, a takeup core configured to receive a ribbon from each of the first ribbon spool and second ribbon spool, and a load applicator configured to limit movement of the second ribbon spool.
In another embodiment, the invention relates to a ribbon tension control assembly for maintaining substantially constant tension in a ribbon, the assembly including a payout core having a cylindrical shape, a first ribbon spool mounted on the payout core and attached thereto, a second ribbon spool mounted on the payout core, the second ribbon spool configured to move independent from the payout core, a takeup core including a first cylindrical core that rotates independent of a second cylindrical core, where the first cylindrical core is configure to receive a ribbon from the first ribbon spool and the second cylindrical core is configured to receive a ribbon from the second ribbon spool, and a first control mechanism configured to control a rotation of the second cylindrical core in a first direction, and a load applicator configured to control a rotation of the second ribbon spool.
Referring now to the drawings, embodiments of ribbon tension control assemblies that provide substantially constant tension to a ribbon are illustrated. In some embodiments, the ribbon tension control assemblies include a payout core having a cylindrical shape, a first ribbon spool mounted on and attached to the payout core, and a second ribbon spool mounted on the payout core, where the second ribbon spool is configured to move independent from the payout core. In such case, the ribbon tension control assemblies also include a takeup core configured to receive a ribbon from each of the first ribbon spool and second ribbon spool, and a load applicator configured to limit movement of the second ribbon spool, thereby maintaining substantially constant tension on both ribbons during operation.
In a number of embodiments, the tension control system includes a single drive source such as a drive motor for driving either the payout core or the takeup core. In other embodiments, the tension control system includes a drive motor for each of the payout core and the takeup core. In several embodiments, the tension control systems provide for substantially constant tension in multiple ribbons, and, as a result, the multiple ribbons effectively appear as a single ribbon medium for printing assemblies used in conjunction with the tension control systems.
In several embodiments, the load applicator is configured to make contact with an o-ring shaped elastomer positioned around the circumference of the second ribbon spool. In other embodiments, the load applicator is configured to make contact with a ring shaped braking disc positioned around the circumference of the second ribbon spool. In such case, the takeup core can include a first cylindrical core and a second cylindrical core where the first core rotates independently of the second core by way of a one way clutch.
Embodiments of tension control systems described herein can be extended to other media besides ribbons. For example, the tension control systems can be applied to other systems where media in two different panel thicknesses or two different spool diameters needs to be dispensed with substantially even tension using one drive system. In several embodiments, the tension control systems can be used with two or more ribbons or other suitable media that is intended to be dispensed substantially simultaneously using one drive system.
In operation, a spring loaded arm 30 of the load applicator 14 applies pressure to the elastomers 28 such that a friction force opposes rotational motion of the silver ribbon spool 18 on the payout core 26. While the black ribbon spool 22 is generally attached to the payout core 26, the silver ribbon spool 18 can rotate free of the payout core 26. The movement of the silver ribbon 20 is therefore controlled by a takeup drive motor (depicted as block 27) attached to the takeup assembly 16. The load applicator 14 ensures that little or no loose slack exists in the silver ribbon 20 as it is drawn by takeup assembly 16. The movement of the black ribbon 24 is controlled by a payout drive motor (depicted as block 29) that controls rotation of the payout core 26 and/or the takeup drive motor 27.
In operation, the dual ribbon tension control assembly can effectively make the black and silver payout cores independent while providing substantially constant tension to the free floating silver payout core such that the assembly can handle ribbon spools having different outer diameters and ribbons of different thicknesses.
In one embodiment, the payout core 26 is made of a polymer such as Nylon 6/6, acrylonitrile butadiene styrene (ABS), or other suitable materials. In one embodiment, the takeup core is made of a polymer such as Nylon 6/6, Acrylonitrile butadiene styrene (ABS), polycarbonate, or other suitable materials. In the embodiment illustrated in
The black ribbon spool 22 is affixed to the first core 26a by use of a press or interference fit where an internal diameter of the black ribbon spool 22a is slightly less than the first core diameter 26d. In such case, the black ribbon spool 22 is forced onto the first core 26a and, in most embodiments, cannot move independent of the payout core 26.
The silver ribbon supply spool 18 is positioned over an area 42c defined by an ISO height limit of the credit card 42 reserved for embossed text. The placement of the silver ribbon spool 18 is such that it allows the printer to print the digits of the credit card number, expiration date, name and other information on the front of the credit card in the lower card area 42c. In many embodiments, a dual ribbon tension control assembly including the payout assembly can be used to print to both sides of a credit card without the need to reload or reconfigure the payout assembly with different spools.
In one embodiment, the load is applied directly to the outer diameter of the silver ribbon supply spool. The tension on the spool is maintained substantially constant by using a torsion spring in series with an extension spring. One leg of the torsion spring can apply load force to the ribbon spool while the other leg of the torsion spring can be pulled to an angle using the extension spring. As the silver supply spool pays out and becomes smaller in diameter, the extension spring pulling on the torsion spring ensures that the load force applied remains substantially constant.
The dual ribbon tension control assembly includes the payout assembly 112, the load applicator 114, the takeup assembly (not shown), a silver ribbon spool 118 for a silver ribbon 120, and a black ribbon spool 122 for a black ribbon 124. The payout assembly 112 is mounted within a housing of the printer 100 and includes a payout core 126. The silver ribbon spool 118 and black ribbon spool 122 are mounted on the payout core 126. The silver ribbon spool 118 has a cylindrical shape and includes a braking disc 128 having a ring shape that extends along a circumference of the cylindrical shape at an end of the silver ribbon spool 118.
In operation, a spring loaded arm 130 of the load applicator 114 applies pressure to the braking disc 128 such that a friction force opposes rotational motion, or motion in the direction of ribbon payout (e.g., the first direction 129), of the silver ribbon spool 118 on the payout core 126. While the black ribbon spool 122 is generally attached to the payout core 126, the silver ribbon spool 118 can rotate free of the payout core 126. The movement of the silver ribbon 120 is therefore controlled by a takeup drive motor (not shown) attached to the takeup assembly (see
In one embodiment, the braking disc is made of a metal such as steel. In other embodiments, the braking disc can be made of other suitable materials.
The black ribbon spool 122 is affixed to the first core 126a by use of a press or interference fit where an internal diameter of the black ribbon spool 122a is slightly less than the first core diameter 126d. In such case, the black ribbon spool 122 is forced onto the first core 126a and, in most embodiments, cannot move independent of the payout core 126.
Referring now to
In another embodiment, the load/friction force on the silver supply spool can be applied using magnetic resistance. In such case, a bi-metal disc made of a steel core with a copper layer around it is attached to, and extends around a circumference of, the silver supply spool. A series of magnets can be placed in a semi-circular arc positioned proximate yet radially beyond the bi-metal disc. The use of magnetic resistance as a load/friction force in this embodiment is similar to the use of magnetic resistance in stationary bicycles.
While the above description contains many specific embodiments of the invention, these should not be construed as limitations on the scope of the invention, but rather as examples of specific embodiments thereof. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their equivalents.
In several of the embodiments described herein, the tension control system is used in conjunction with ribbon spooling systems for printing. In other embodiments, the tension control system can be used with cable spooling systems or other systems having media wound on one or more spools.
The present application claims priority to and the benefit of Provisional Application No. 61/368,993, filed Jul. 29, 2010, entitled “SYSTEMS AND METHODS FOR CONTROLLING TENSION IN A RIBBON SPOOLING ASSEMBLY”, the entire content of which is incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
3554349 | Hebert | Jan 1971 | A |
4079899 | Vogel | Mar 1978 | A |
4343837 | DeLorenzo | Aug 1982 | A |
4573645 | Harris, Jr. | Mar 1986 | A |
4606662 | Komplin | Aug 1986 | A |
5486057 | Skinner et al. | Jan 1996 | A |
5653397 | Park | Aug 1997 | A |
6250825 | Kazo et al. | Jun 2001 | B1 |
6899478 | Mucelli et al. | May 2005 | B1 |
7150572 | McNestry et al. | Dec 2006 | B2 |
7234884 | Tratar | Jun 2007 | B1 |
7349002 | Kanemaru et al. | Mar 2008 | B2 |
7626604 | Ihara | Dec 2009 | B2 |
7963438 | Brown et al. | Jun 2011 | B2 |
8529050 | Vandermeulen | Sep 2013 | B2 |
20070228158 | Brown et al. | Oct 2007 | A1 |
20080219744 | Valverde et al. | Sep 2008 | A1 |
Number | Date | Country |
---|---|---|
63312877 | Dec 1988 | JP |
63312878 | Dec 1988 | JP |
04189583 | Jul 1992 | JP |
2005313528 | Nov 2005 | JP |
Entry |
---|
IBM Technical Disclosure Bulletin, Nov. 1979, vol. 22, Issue 6, pp. 2327-2329. |
IBM Technical Disclosure Bulletin, Sep. 1980, vol. 23, Issue 4, pp. 1517-1520. |
IBM Technical Disclosure Bulletin, Jun. 1983, vol. 26, Issue 1, pp. 292-293, 299-300. |
IBM Technical Disclosure Bulletin, Jan. 1985, vol. 27, Issue 8, pp. 5018. |
https://sdp-si.com/ss/PDF/79005059.pdf, “Sinch Roller Clutches Technical”, downloaded Jun. 21, 2010, 2 pages. |
Number | Date | Country | |
---|---|---|---|
20120027492 A1 | Feb 2012 | US |
Number | Date | Country | |
---|---|---|---|
61368993 | Jul 2010 | US |