The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 26, 1995
Filed:
Dec. 10, 1992
Ronald B Howes, Jr, Minneapolis, MN (US);
Thomas R Emmons, Minneapolis, MN (US);
Dennis J Warwick, Richfield, MN (US);
DataCard Corporation, Minnetonka, MN (US);
Abstract
A method and apparatus for a two-pulse solenoid embossing system implementing an amplitude feedback circuit, i.e., current monitor (48), to provide precise amplitude and timing control over two current pulses (4, 5), and thereby provide precision control over the position and velocity of the embossing system's print elements (64a, 64b). To maintain the current amplitude during the second current pulse (5), the method and apparatus alternatively switches the power on and off to the solenoid coils (55) with a frequency such that a substantially constant current amplitude is maintained in the solenoid coils (55). The embossing system provides an improved solenoid body assembly (61) including a first stack of steel laminations (93), a center block (82) and a second stack of steel laminations (81). A plunger (62) is slidably connected to the solenoid body assembly (61) by shaft (63). Cavities (79) receive dowel pins (71) which are attached to plunger (62). The cavity and dowel pin arrangement (79, 71) prevents the plunger (62) from rotating.