| 摘要 |
1,138,034. Automatic control of speed. L. SCHULER G.m.b.H. Aug.31, 1967 [Sept.23, 1966], No. 39908/67. Heading G3R. In a system for keeping one or more machines 1, e.g. presses, in a production line in synchronism with a master machine or reference 2 by adjustment of its speed in a correcting sense when the phase deviation, detected at 5, reaches a first predetermined value, a further and smaller adjustment is made in the opposite sense when the deviation has dropped to a second, lower, value. Each machine is driven by a three phase commutator motor whose brushes are moved by a servomotor 11, which is energized for a finite time by a relay 9 (for positive errors) when a phase error great enough to close a relay 6 has persisted for a time determined by a delay switch 7. After a further time, determined by 12, the relay 6 is "tested" at 13 and if it is still energized (i.e. the error has persisted) a further adjustment in the same direction is made by relay 9. The relay 6 drops out when the phase error has dropped to half, when after a time 14 a relay 16 is closed for a short time to energize the servomotor 11 in the opposite direction. A similar arrangement corrects for negative errors, via relay 18, and the time intervals can be different from those pertaining to positive errors. It is stated that the adjustment made when the phase error has decreased may be in two stages, the second smaller than the first, and that the correcting servomotor may be run for a time proportional to the speed or phase deviation. |
