Continuous form printer having multiple feed sensors and method

A method for feeding continuous form paper along a paper path of a printer, the paper having a discrete page length defined by perforations in the paper, the method comprising:

• setting a first predetermined feeding interval from a plurality of settable feed intervals;
• repeatedly feeding the paper by the first predetermined feeding interval;
• detecting a leading edge of the paper;
• feeding the paper by a number of the first predetermined feeding intervals corresponding to the distance between the leading edge of the paper and a predetermined position along the paper path, until the leading edge of the paper reaches the predetermined position along the paper path, the predetermined position based on the discrete page length, the first predetermined feeding interval, and the detection of the leading edge;
• and
• starting a printing process when the leading edge of the paper reaches the predetermined position;
• wherein the feeding the paper until the leading edge of the paper reaches the predetermined position further comprises:
• monitoring feed interval signals;
• measuring a feeding amount between the detecting of said leading edge and until a subsequent feeding interval signal detecting said leading edge of the paper;
• setting a feeding adjustment amount based on the page length, the measured feeding amount, and the first predetermined feeding interval, the feeding adjustment amount defining a distance from the leading edge to the predetermined position;
• and
• feeding the paper by the feeding adjustment amount until the leading edge of the paper reaches the predetermined position.

A method for feeding continuous form paper along a paper path of a printer, the paper having a discrete page length defined by perforations in the paper, the method comprising:

• setting a first predetermined feeding interval from a plurality of settable feed intervals;
• repeatedly feeding the paper by the first predetermined feeding interval;
• detecting a leading edge of the paper;
• feeding the paper by a number of the first predetermined feeding intervals corresponding to the distance between the leading edge of the paper and a predetermined position along the paper path, until the leading edge of the paper reaches the predetermined position along the paper path, wherein the feeding the paper until the leading edge of the paper reaches a predetermined position along the paper path further comprises:
• counting a number of phase pulses output by a driving mechanism for feeding the paper, from a time at which the paper top sensor senses the leading edge of the paper until a time at which a next predetermined feeding interval is sensed,
• calculating a number of predetermined feeding intervals to be performed based upon the first predetermined feeding interval, the discrete page length, and the number of phase pulses counted, and
• feeding the paper until the calculated number of predetermined feeding intervals have been performed;
• and
• starting a printing process when the leading edge of the paper reaches the predetermined position.

A mechanism for feeding continuous form paper having a discrete page length defined by perforations between pages of the paper and having feed holes in the paper, comprising:

• drive means for driving at least one tractor;
• said at least one tractor feeding the paper by the feed holes along a paper path;
• signal generating means for generating at least a first and a second feeding signal corresponding to a first and a second feeding interval, respectively, wherein said signal generating means comprises a first signal generator, associated with said tractor, for generating said first feeding signal corresponding to said first feeding interval of said printer, and a second signal generator, associated with said tractor, for generating said second feeding signal corresponding to said second feeding interval of said printer;
• a signal selector for selecting one of said feeding signals;
• and
• a controller for controlling said drive means to drive said tractor to feed the paper by said feeding interval corresponding to said selected signal.