Image Number 3 for United States Patent #4223821.
A press-feed unit is operative to feed a length of stock material to a press. The unit comprises a body for fixing adjacent the press and a transport section reciprocable relative to the body by a pneumatic piston and cylinder assembly, the stock being clamped to the transport section during forward feed strokes of the latter. The unit further comprises a control valve, and a transport feed valve which is controlled by a pilot pressure signal from the control valve and operable to feed the transport cylinder. A pilot signal connection is provided which can be blanked off to enable the unit to operate independently, or connected through a pilot pressure pipe to a basically similar unit to provide a duplex arrangement of two units, one of which is directly controlled in dependence on press ram position and provides a pilot signal through said pipe to operate the transport feed valve of the other unit.