All Powair units incorporate a reversing feature as standard, enabling them to be positioned either way round on the press. In certain circumstances, using a unit in the reverse mode can be an advantage. For forward operation one of the two screws is tightened and the other can be adjusted to give the required speed, and for reverse operation the screws remain in the holes but exchange functions.
Where tools with pilots are to be used, Powair will supply units which have a simple calve arrangement whereby clamping is momentarily released just as the pilots enter, then clamping is re-applied immediately they are 'home'. The material is thus always under control, either by the clamps or the pilots.
Powair feeds can be supplied with a trigger which is operated by a striker fitted to the press ram. The trigger remains deflected during the down stroke so the material s firmly clamped, then as it is released on the upstroke it intialises the feeding sequence. A reverse feature allows feed in either direction.
Where there are frequent set-up changes which would mean resetting the tripping action with Trigger Operation, an alternative is to use a Powair remote control feed. In this case either an electrical switch or a pneumatic valve mounted from the press frame is tripped by a cam added to the end of the crankshaft. Thus the action is independent of the press stroke setting or the tools being used.
Where feed lengths are required in excess of the maximum stroke setting of a particular unit, Powair can supply an electronic repeater control system which is capable of initiating up to 99 feed movements for each stroke of the press. The system also allows normal single stroking operation, being readily switchable between the two.
When required the feeder can be fitted with safety guards. They completely enclose the moving parts yet allow full access for adjusting the stroke and can be easily removed when necessary