| 摘要 |
<p>1,266,922. Feeding metal sheets to shears. B.R.G. 17 April, 1969 [17 April, 1968], No. 19761/69. Addition to 1,104,522. Heading B3W. In a shear for cutting an approximately circular blank from a metal sheet by a succession of straight cuts while the sheet is rotated on a centring carriage 37 slidable on rails 7 and located in selected position by stops 21 including means for micrometric adjustment and springs biasing the carriage towards the shear (not shown), the carriage includes means for shifting the sheet angularly in adjustable feed steps in phase with the actuation of the shear. The sheet rests on an upstanding rubber rim 38a on a rotatable table 38 and is retained thereon by vacuum applied via a hollow spindle 45 and controlled by a handle 40a or by a bolt screwed into the spindle and extending through the sheet. The table 38 is coupled to an oscillatable drive-plate 44 by rollers 46 which engage in ratchet teeth 44c on the plate and, by a wedge action, rotate the spindle in the clockwise direction only. The plate 44 is oscillated by a single-acting jack 42 and a compression spring 43, the stroke of the plate 44 under the action of the spring 43 being limited by engagement of an adjustable barrel cam 39a with a stop 44b on the plate. The fluid supply to the jack 42 is linked to the fluid supply to a hold-down 9 of the shear to cause the feed step of the table 38 to take place while the hold-down is inoperative.</p> |
