In fixed phase angle Stirling cycle engines, which is a typical form of hot gas energy transforming device, there is generally provided a power piston and a displacer piston powered by the power piston. The engine is usually constructed using a predetermined and fixed phase angle between the power piston and the displacer piston so that maximum engine power is obtained. This predetermined phase angle may be 90.degree.. For better understanding, phase angle is described as the distance the displacer piston leads the power piston in the direction of rotation. For example: if displacer piston leads power piston in clockwise rotation, the engine will then run clockwise. Thus, by modifying or changing the piston phase relation, it is possible to control the engine's power output from zero power to maximum power output in either rotational direction.
Typically, power transmission from the power piston to the displacement piston and drive shaft or power take off are accomplished through gears and levers as taught by U.S. Pat. Nos. 2,508,315; 2,885,855; 3,077,732; 3,416,307; 3,416,308; and 3,482,457.
As taught by the referenced patents, the mechanism is excessively complex, requires numerous operable components, has considerable power loss due to friction and because of the number of components required there is considerable economic expense for their production.
There has not been an entirely satisfactory means for transmitting the power from the power piston to the displacement piston and output power drive shaft until the emergence of the present invention.