Oscillograph for recording graphic art patterns - has two concentrically mounted pendulums whose centres of rotation are almost superimposed

摘要

A tracing arm acts on a oscillating platform which has a pendulum mounted underneath it. This has a semi spherical shape which locates in one of two concentric cups mounted in a hole on a table. Two sets of ball bearings keep friction to a minimum and allow the pendulum to turn on themselves to increase the range of possible traces. Variation of the relative movement between the two pendulums is controlled by adjustment of the respective counterweight to adjust the respective periodic movement. Appropriate fixing methods allow vertical or horizontal displacement of the table if a ballast fluid is added or removed.