| 摘要 |
1276603 Programmed control of machines DOALL CO 11 Aug 1970 [21 Aug 1969] 38658/70 Heading G3N [Also in Division G4] The magnitudes of the mutual displacements and velocities between machine elements (5, 6); (6, 7); (8, 7) Fig.1 (not shown) are measured digitally by counting the traverse, and rate of traverse of interference fringes produced by interferometers of the Michelson type, 10, Figs.1, 2 (not shown) with a photo-sensitive detector (15) Fig.2 (not shown), mounted on the elements (6,7) Fig.1 (not shown), with reflecting devices 11 for one of the respective interfering beams on elements (5, 6, 8) Fig.1 (not shown). Bi-directional counter 18, and frequency meter 19 comparing the rate of fringe traverse with a known timebase, for displacement and speed respectively output to digital comparators 20, 21 which control servo 22 to move the respective machine elements, such as 5 by means of a respective hydraulic prime mover 9. A hydraulic motor and lead screw may be used. The machine is controlled by a program tape reader, or decoder 17 whose outputs provide the other signals for the comparators 20, 21. Deceleration is maintained within the capabilities of the servosystems, as desired positions are approached. For manual control of displacement and speed, overides 23, 24 are provided. The monochromatic light for the system is provided by a laser (12) Fig.2 (not shown). A single laser (25) Fig. 4 (not shown) may supply light to all the machine elements to be controlled, beam-splitting semi-reflecting devices (26) Fig. 4 (not shown) being used. The resolution of the comparator 20 may be adjusted to vary machining accuracy. |
