| 摘要 |
740,640. Recording-apparatus. SWARTWOUT CO. May 18, 1953 [Aug. 8, 1952], No. 13892/53. Class 106 (4). A strip chart P reverses its direction of movement by passing around the edge 4 of a transversely curved plate 5 so that the chart is shaped to the curvature of the edge which corresponds to the arc of movement of a pen 11 marking the chart adjacent ot the edge. The strip of paper P is drawn from a supply roll S, round a side edge 4 of the backing plate 5, across the face of the plate 5, around a drive sprocket roll D on to a take-up spool F. The roll D has two spaced sets of teeth 6 engaging rows of perforations 7 in the paper P and the perforations 7 are larger than the teeth to allow for expansion or shrinkage due to variations of humidity. A pen arm 10 rotates about an axis A, parallel to the direction of movement of the paper P over the plate 5, and carries the pen 11 adjacent the edge 4 which is arcuately curved about the axis A so that the paper P is linearly inscribed as it doubles back on itself round the edge 4. A similarly curved face 14, preferably lined with felt 15, of an adjustable bracket 13 ensures close conformity of the paper to the shape of the edge 4 which is rounded for smoothness. The instantaneous value of the variable may be indicated by a pointer on the pen arm 10 against a curved scale 23.
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