Abstract: Apparatus for following the sun using the sun's radiant energy to heat a fluid-containing sensor to create a pressure which is used to rotate the apparatus against a spring force provided by an expansion bellows. The sunlight is permitted to strike the sensor only for certain angles of incidence to the apparatus so that the fluid pressure and the spring force rotate the apparatus to a predetermined position relative to the angle of incidence. In one embodiment, sunlight passing through a filter including several parallel plates which allow passage of sunlight having a predetermined angle of incidence relative to the filter is focused on the sensor. A reflector focuses sunlight on the sensor to reposition the apparatus to the desired position when the apparatus is incorrectly positioned because the sun has been obscured by clouds. In two alternative embodiments, a fresnel lens and a parabolic reflector, respectively, focus sunlight having a predetermined angle of incidence onto the sensor.

Abstract: Apparatus for following the sun using the sun's radiant energy to heat a fluid-containing sensor to create a pressure which is used to rotate the apparatus against a spring force provided by an expansion bellows. The sunlight is permitted to strike the sensor only for certain angles of incidence to the apparatus so that the fluid pressure and the spring force rotate the apparatus to a predetermined position relative to the angle of incidence. In one embodiment, sunlight passing through a filter including several parallel plates which allow passage of sunlight having a predetermined angle of incidence relative to the filter is focused on the sensor. A reflector focuses sunlight on the sensor to reposition the apparatus to the desired position when the apparatus is incorrectly positioned because the sun has been obscured by clouds. In two alternative embodiments, a fresnel lens and a parabolic reflector, respectively, focus sunlight having a predetermined angle of incidence onto the sensor.

Abstract: An automatic blade angle controller system capable of maintaining a blade an earth-working tool level with the ground. A transparent, closed manometer partially filled with an opaque liquid is contained in an opaque enclosure. A light source is located within the perimeter of the manometer. Two solar cells are located on opposite sides of the enclosure in such manner that the light from the light source must pass through the manometer before impinging on the solar cells. The opaque liquid partially blocks the light from impinging on the solar cells. The voltages from the solar cells are subtracted resulting in an error signal. Of course, when the two voltages are of equal value, no error signal is produced, thereby establishing a level reference position for the enclosure. The enclosure is rigidly affixed to the blade, thereby establishing a reference position for the blade. A servo-hydraulic system returns the blade to its reference position upon receipt of the error signal.

Abstract: A torque converter that uses the reaction of energy storing devices to mechanically convert a given input angular velocity into an output torque. The torque converter is comprised of an input shaft which delivers an oscillatory motion to an inertia device, such as a flywheel, through connecting rods and lever arms. The inertia device transfers the oscillatory motion to the output shaft through differential gears and overrunning clutches. In the preferred embodiment, two inertia devices mounted on parallel axes with each 90.degree. out of phase provide a smooth, continuous output torque.