1. Field of the Invention
This invention relates to record feeding apparatus and methods.
2. Brief Description of the Prior Art
Prior art U.S. patents to Martin, U.S. Pat. No. 2,300,625 and Masterson et al., U.S. Pat. No. 3,350,091 relate to apparatus for feeding sheets longitudinally while being guided at a side edge by an edge or side guide. Apparatus of this type generally involve a considerable number of parts, gears or pulleys and a special arrangement of bearings.
Various motor control circuits for controlling the feeding of a record web through record printing machines are known. Such systems generally use a continuously running motor coupled to a web advancing mechanism by means of a clutch mechanism which serves periodically to transmit power from the motor to the advancing mechanism for advancing the web. Other systems may use periodically energized motors or stepping motors for advancing the web.
Whereas these techniques serve to advance a web through a printing mechanism or the like, systems employing a clutch or periodically energized motors tend to be inaccurate in the positioning of the web in the printing mechanism. Stepping motor systems require a compromise to be made between step size and the accuracy of positioning because if the steps are made small enough to accurately position the web, the rate of advance is relatively slow unless excessively high stepping rates are used. If large enough steps to provide an acceptable advancing rate are used, inaccuracies in web positioning result.