| 摘要 |
1478208 Automatic control of speed RENGO KK and NIPPON RIRAIANSU KK 23 July 1975 [29 Oct 1974] 30900/75 Heading G3R In a rotary cutter control system for cutting a continuously fed web into desired lengths, an actual web speed signal is multiplied by a coefficient equal to pre-set values of the cutter circumference and the desired length. The cutter speed is controlled according to the combination of the multiplier output and the difference between this output and the actual cutter speed. As shown, in Fig. 3, the desired length L of the web e.g. cardboard and the circumference I are set digitally at a and b, their quotient K being derived by circuit c upon completion of cutting as sensed by device OP. The actual web speed signal from tachogenerator PG A is phase shifted, multiplied at d by K to form a signal K# A which is compared in a digital-analogue converter M with the phase shifted actual cutter speed signal from tachogenerator PG B . The result of the comparison is combined by adder n with the signal K# A , from multiplier d via frequency to voltage converter k, to form the speed control signal V o for a motor driving the rotary cutter. The outputs of tachogenerators PG A and PG B are said to be pulse signals. |
