The loading system called Touch Down by the company itself was introduced by Sheaffer in 1949 for the homonymous models, and is nothing more than a more sophisticated reworking, carried out after twenty-five years (patent nº US-2610612), of the Chilton pneumatic filler system (whose patent, nº US-1528379, is mentioned explicitly). In fact, the operating principle is essentially identical, what changes is the way in which the pneumatic compression of the rubber sac inside the pen is carried out.
Also in this case there is an unscrewable bottom that is hooked to a metal cylinder that slides hermetically thanks to a gasket along the body of the pen, the mechanism is however much more complex to avoid the use of the ventilation hole on the bottom of the pen and allow compression only by pushing down the tube anchored to the bottom once you have extracted it.
In this case, the compression takes place by passing the air in the cavity through not a hole on the tip of the cap but short lateral grooves at the two ends of the inner tube. When opening the grooves on the bottom allow the expansion of the bag, closing the piston the slide is sealed and the internal air compresses the sac, at the end of the course the other grooves allow the air to escape and the expansion of the sac loads the ink.
- Patent n° US-1607048, of 1926-11-16, requested on 1925-07-18, of Edward Bergquist, Unbranded. Pen-filling mechanism.