摘要 |
<p>A balance beam has a fulcrum, at least one bellows (connected to a source of pressure or vacuum) acting on the beam and a connection to the armature of a differential transformer at one end. A poise is mounted for movement along the beam by rollers riding on shoulders formed on the beam. A carriage having a connection to the poise at the elevation of the axes of the rollers moves the poise and is, in turn, driven by a screw turned by a servo-motor controlled by the differential transformer. Provision is made for minimizing temperature error both longitudinally and transversely of the beam. The fulcrum and bellows may be moved to different locations relative to the beam, using spaced drilled holes in the beam and the base plate. Various readouts may be connected to the screw, and recorders and control devices may also be driven by the screw.</p> |