Double crankshaft reciprocating engine

A double crankshaft reciprocating engine, wherein it comprises:

• a plurality of cylinder assemblies, comprising:
• a cylinder, which is provided with cylinder air inlets and an intake valve at the top;
• a piston, which is mounted in the cylinder, the piston and an inner wall of the cylinder located above the piston form a combustion chamber;
• the piston is provided with first vent holes and a first exhaust valve for controlling the on-off of the first vent holes;
• and
• a displacer, which is mounted in the cylinder and located below the piston, a cylindrical space between the displacer and the piston is a compression chamber;
• the displacer is provided with second vent holes and a second exhaust valve for controlling the on-off of the second vent holes;
• and
• a double crankshaft transmission system, comprising:
• two crankshafts provided in parallel, each crankshaft comprises a plurality of cranks, a plurality of the corresponding cranks of the two crankshafts constitute a plurality of crank pairs, and each of the crank pairs is mirror symmetric with respect to a YZ plane;
• and
• a plurality of rhombic drive mechanisms, which are connected to the two crankshafts by means of the crank pairs;
• wherein each rhombic drive mechanism is connected to the piston and the displacer of one of the cylinder assemblies;
• a pair of transmission gears of the rhombic drive mechanism are mounted on the front ends of the two crankshafts and mesh with each other;
• wherein a midpoint of a connecting line of centers of the pair of transmission gears is defined as the origin O of an XYZ coordinate system, the connecting line of centers is defined as the X-axis direction, a direction parallel to the axis of the transmission gears is defined as the Y-axis direction, and a vertical direction is defined as the Z-axis direction.