| 摘要 |
<p>Apparatus and circuit for increasing the range of control of diaphragm controlled pressure reducing valves, esp. for control of O2 pressure in precision cutting/burning operations, in which the reduced pressure indicated by a reduced pressure manometer is sensed electronically - pref. photoelectrically - the signals so produced being used to actuate an adjusting device utilising logical circuits, two photodiodes being used for the defining set value and being covered by a pointer on the manometer when the set value and indicated reduced pressure correspond during deviations of the reduced pressure from the set value, the direction of variation being established directly in dependence on the motion of the pointer.</p> |
