Print Shuttle

Here is an IBM 1443 printer print shuttle,
below its storage
and above a slide rule for scale

This computing artefact consisted of the print shuttle
with just 7 of its full compliment of 13 print elements.

Unlike the train/chain/band which rotated around two wheels at high speed,
the print shuttle used on the IBM 1443 printer moved backwards and forwards.

Print elements containing 13 metal leaves
with a type element at the end
were held by spring clips in slots in a hollow aluminium bar.
The 1443 printer did not have an inked ribbon
the the full width of the hammer bank
but a narrow one fed across by two spools on either side.

Because the print shuttle had to stop and reverse direction for every
line printed it was not as fast as the line printers
that had loops of print elements spinning round continuously,
and could only manage about 120 lines per minute.

It had another weakness though.
As the ribbon got worn it could become frayed,
especially if you tried to save money by re-inking ribbons.
Then a type element could snag the frayed ribbon
and unspring the type element and others.
There would be a mess of elements and ribbon in the printer.

Back to Line Printer.