Linear combustion engines with valve in piston

A linear generator comprising:

• a combustion module;
• and
• at least one linear motor, each linear motor having at least one piston, the piston comprising:
• a piston head having an opening therein;
• a piston skirt opposed to the piston head;
• a piston side wall extending between the piston head and the piston skirt, the piston head, the piston skirt and the piston side wall co-operating to define an interior piston volume, the piston side wall having at least one port therein to provide a pathway between the interior piston volume and an exterior piston volume;
• and
• a valve mechanism movable relative to each of the piston head, the piston skirt and the piston side wall, the valve mechanism including:
• a valve stem extending through the piston skirt and the interior piston volume into a mover shaft of the motor;
• and
• a valve head coupled to the valve stem and configured to cover the opening of the piston head;
• wherein the valve mechanism is movable between a first position where the valve head is covering the opening of the piston head and a second position where the valve head extends outwardly from the piston head into a combustion chamber of the combustion module to expose the opening and provide a pathway between the interior piston volume and the combustion chamber.