| 摘要 |
<p>in a printer having a print head assemblage (18) longitudinally moving along a path parallel to a record medium (16) a portion of the print head assemblage is controlled to strike the record medium of a desired point by measuring the time required for sonic pulses generated in a rod (36) at the position of the print head asssemblage to arrive at a sensor, (34) such time being a function of the distance from the print head assemblage to the sensor. A representation of this time is compared against a similar representation of a time associated with the position of the desired point and upon equality the portion of the print head assemblage is driven toward the record medium.</p> |
