| 摘要 |
<p>945,049. Drilling machine details; metal strip feeds. ETABLISSEMENTS SIRUGUE & CIE. Sept. 11, 1961 [Sept. 9, 1960], No. 32465/61. Headings B3C and B3W. [Also in Division H2] A work-table 1, e.g. on a punching, drilling boring, or welding machine, is driven along a bed 2 by an electric motor, the work-table also carrying photo-electric units 19-21 and 22-24 co-operating with riders 4 adjustably mounted on the bed 2; the arrangement is such that, when a light beam is interrupted by a rider, the motor is de-energized and an electromagnetic brake applied. The run-on, however, carries the photo-electric unit passed the rider and when the light beam is re-established an unspecified locking means is operated to positively stop the carriage. Each unit comprises two photocells illuminated by a single lamp and either or both of two operating cycles are initiated simultaneously with the de-energization of the motor according to whether either or both of the two cells are obscured by the rider 4. The two separate units may be arranged so that the operations are performed on both the forward and return runs of the carriage, the difference in their positions shown being equal to twice the run-on. The photo-cells operate through transistor circuits (Fig. 2, not shown), the locking device being operated for the time taken for a capacitor to re-charge after being discharged when the beam was interrupted. Specification 874,597 is referred to.</p> |
