Claims
- 1. A document transfer mechanism for transporting a document along a document transfer path, comprising:
- belt means passing over first and second wheel means mounted adjacent to said document transfer path for aligning a segment of said belt means with the document transfer path;
- at least one spur means projecting from said belt means for engaging the trailing edge of a document positioned on the document transfer path between the first and second wheel means;
- drive means for moving said drive belt means and pushing a document from the first wheel means to the second wheel means; and
- accelerator means driven in synchronism with said drive means for engaging the leading edge of a document approaching the second wheel means and increasing the transport speed of the document relative to said belt means, thereby disengaging said spur means from the trailing edge of said document means prior to said spur means passing over said second wheel means.
- 2. The invention of claim 1 wherein said accelerator means comprises at least one pair of roller means mounted on both sides of the document transfer path, the nip of said roller means being positioned for engaging the leading edge of said document, said roller means being driven by said drive means.
- 3. The invention of claim 2 wherein said accelerator roller means is connected by a belt to a third wheel mounted on a shaft upon which said second wheel means is axially mounted.
- 4. The invention of claim 1 wherein said drive means drives said belt means and said accelerator means in incremental steps.
REFERENCE TO CO-PENDING APPLICATION
This application is a division of pending application Ser. No. 449,131 filed Dec. 13, 1982, abandoned as of the filing date of the present application.
1. Field of the Invention
This invention relates to an embossing system for embossing characters on a sheet medium such as a plastic credit card.
2. State of the Prior Art
Embossing systems are in widespread use. Two such systems are shown in U.S. Pat. Nos. Re. 27,809 to Drillick and 4,088,216 to LaManna et al both of which are assigned to Data Card Corporation. Both of those systems are of substantially greater mechanical complexity and size in their embossing mechanism and may, therefore, require a relatively larger amount of maintenance and power to operate.
In the machine of U.S. Pat. No. Re. 27,809, a blank card is indexed along a card track past an array of punches and dies longitudinally arranged along the card track at a fixed height. Characters are embossed on one line of the card when the desired space is positioned adjacent a related die and punch pair on opposite sides of the card. A pair of bail arms driven in coordinated reciprocating or oscillatory movement by eccentric arms driven by an eccentric which is in turn driven by a motor-driven drive shaft provides the embossing pressure for the punch and die elements. Electromechanical interposers are utilized to couple movement of the bail arms to actuate a particular punch and die pair. A separate pair of interposers is required to be actuated and moved for each operation of a punch and die pair which results in a machine having a high degree of electromechanical complexity.
In the machine shown in U.S. Pat. No. 4,088,216 cards are supported in an X-Y access controlled positioning mechanism which places the proper portion of the card surface in alignment with a selected punch and die member mounted around the circumference of a punch and die wheel coaxially mounted on a single hub driven by a drive shaft. The angular position of the wheel selects the proper punch and die pair from the wheel. Bail arms driven by an eccentric link from a drive shaft apply the embossing pressure to the selected punch and die pair. Motion of the bail arms is converted to movement of the punch and die by actuating interposers positioned between the bail arms and the punch or die elements carried by the wheels. The interposers provide a mechanical coupling between the bail arm and the punch or die. The bail arms are indicated in the patent as necessary to allow for unobstructed rotation of the punch and die wheel while the bail arms continuously reciprocate or oscillate. The use of interposers which must be actuated and electromechanically moved on each mechanical cycle of the machine greatly increases the complexity of the machine.
In the embossing machine shown in U.S. Pat. No. 4,378,733, issued Apr. 5, 1983, a rotating cam was used to drive cam followers mounted on the bail arms. The embossing punch and dies are carried in slots positioned about the circumference of punch and die wheels mounted on a single hub and driven by a single shaft from a single power source. Electromechanical interposers again provide the mechanical coupling between the bail arm movement and the punch and die elements. In order to drive the embossing element into contact with the card the interposers are required to be actuated and moved into the interposing position in order to couple bail arm movement to the embossing elements.
While all of the systems described above are satisfactorily operable, the requirement of using electromechanical interposers between moving bail arms and the movable punch or die elements adds substantially to the mechanical complexity of the machine, thereby reducing its inherent reliability. Furthermore, the use of punch and die wheels mounted on a single shaft requires use of larger print wheels in order to provide coverage of the entire surface of the card to be embossed. Of course, the consequence of using larger print wheels is that they unavoidably have a much higher inertia and are more slowly positioned and require a substantially larger amount of power to drive them. The sensitivity to size is particularly acute because the moment of inertia of the embossing wheels increases exponentially with their radius, thus requiring an exponential increase in motor torque with a corresponding requirement on motor current.
In accordance with one aspect of this invention, there is provided a machine for utilizing a plurality of pairs of cooperative embossing elements positioned on opposite sides of the card to emboss a selected character at a desired imprint location. The machine includes a positioner for positioning the desired imprint location of a card in alignment with an embossing station in the machine. The machine utilizes first and second print wheels rotatably mounted on opposite sides of the path of the card through the machine and each wheel is constructed and arranged for carrying a plurality of cooperative embossing elements about its circumference with each of the elements slidably movable along the axis of the wheel for engaging the card. The machine also includes apparatus for rotating the first and second print wheels for positioning a selected pair of embossing elements at an embossing station and reciprocating means for engaging a selected pair of embossing elements at the embossing station and applying a selected character to the desired imprint location upon a card.
A primary object of the invention is to provide a card embossing mechanism which does not require the operation and movement of an electromechanical interposer to couple movement of a reciprocating oscillatory bail arm to a selected punch and die pair.
Another object of the invention is to provide an embossing mechanism where the embossing element carrying wheels are mounted on separate shafts to avoid interference between a common mounting hub and a card positioned between the embossing wheels thereby reducing the size of the wheel required to emboss the entire surface of a card having a particular size.
A further object of the invention is to provide an improvement to a card indexing arrangement for indexing cards along a card track by engaging an edge of the card with a projection on a continuous belt which includes a segment running parallel to the track and wherein the card can be transferred from one such belt drive to another without damaging projections on the indexing belt.
A still further object of the invention is to provide a servo control system for individual printwheels which causes them to be moved in precise synchronism by separate drive motors in response to a common command signal.
Another object of the invention is to provide an electromechanical interrupter mechanism to decouple the bail arms and print elements to prevent application of full embossing pressure to print elements in the event of failure.
Yet another object of the invention is the provision of a circuit for supplying a rate feedback signal from a position encoder transducer where the differentiation of the position signals occurs subsequent to commutation while utilizing a single differentiation circuit rather than multiple differentiation circuits as is common in the prior art.
US Referenced Citations (10)
Foreign Referenced Citations (2)
| Number |
Date |
Country |
| 1118804 |
Dec 1961 |
DEX |
| 2430292 |
Jan 1975 |
DEX |
Divisions (1)
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Number |
Date |
Country |
| Parent |
449131 |
Dec 1982 |
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Patent Grant
4688785
