Chart Drive
The paper chart is driven past the pen at a steady rate by a clockwork or electrical drive mechanism. One common method is to use a miniature synchronous motor which turns at a constant speed related to the power frequency; a gear-train is used to propel the paper. Industrial strip-chart recorders may have two-speed gear trains that allow a higher speed to be used for initial adjustments of a process or to follow process upsets. Medical and scientific recorders allow a wide range of accurately-controlled speeds to be set.
An "X-Y" recorder drives the chart depending on the value of another process signal. For example, a universal testing machine may plot the tension force on a specimen against its length. Depending on the particular recorder, either the paper chart is moved or else the pen carriage has two axes of motion. Examples of an x-y recorder date back to the 18th century in the form of the steam indicator diagrams used to record pressure and volume in steam engines.
Read more about this topic: Chart Recorder
Famous quotes containing the words chart and/or drive:
“Perhaps in His wisdom the Almighty is trying to show us that a leader may chart the way, may point out the road to lasting peace, but that many leaders and many peoples must do the building.”
—Eleanor Roosevelt (1884–1962)
“Who will go drive with Fergus now,
And pierce the deep wood’s woven shade,
And dance upon the level shore?”
—William Butler Yeats (1865–1939)