| 摘要 |
1,145,384. Photographic type-composing apparatus. HARRIS -INTERTYPE CORP. 3 May, 1966 [7 May, 1965], No. 19575/66. Heading B6W. [Also in Division H2] In a photographic type-composing apparatus of the sort disclosed in Specification 1,008,146 a stepping motor, 57, Fig. 1, has an output member movable in equal steps, for the transport of film 130, under the control of digital spacing information; a first circuit 55 directs this spacing information as control pulses to motor 57; a selectively operable energy absorbing mechanism is connected to the motor output member for retarding movement thereof and a second circuit 185 operates the energy absorbing mechanism in response to the cessation of digital spacing information. Spacing pulses from space computers 145, justification computer 48 or tabulate control 175 are transmitted to motor 57 and also to OR gate circuit 180, where they establish a D.C. level. When the pulses stop this level drops and a signal passes over line 182 to circuit 185 (including a multivibrator circuit) which produces a single pulse to energize coils 220, Fig. 6. These coils on armature 215 thus form a magnet which then moves on spring plate 217 against brake disc 210. The time constants of the brake control circuit may be such that the pulse delivered to the coils has a short rise time but a longer decay time to enable the stepping motor to reach its proper position. |
