The "crosshead"
testacroce The double-acting steam engines piston can not drive the rod directly.
The closed cylinder does not allow the rod to swing.
A device called the "crosshead" is put between the piston and the rod.
This can be clearly seen in the figure.
The piston is connected to a stem and the stem to the crosshead.
The stem must not swing. The rod, joined at the other side of the crosshead, can freely swing.
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