Abstract: A device for improvement of reciprocating engine efficiency utilizing a free floating weight positioned between compression springs and assembled on each connecting rod. The springs are restrained on the connecting rods at the ends opposite the weights. The weights move on the connecting rods but lag the connecting rod movement because of inertia. The upper and lower springs are alternately compressed and extended due to operating against the weight during engine rotation. The springs are compressed during the deceleration phase of the stroke and extended during the acceleration phase of the stroke. This transfers energy from the deceleration phase to the acceleration phase during engine rotation thereby increasing engine efficiency.

Abstract: A trencher for digging a trench in the ground and being a mobile trencher including ground wheels and a power drive unit and a trencher boom with a digging chain. The trencher boom is pivotally supported about an axis in the trencher, and the ground wheels are driven traction wheels which are located in axially-offset positions to give optimum support for the trencher and resist the reactive forces of the operation of the trencher chain on the remainder of the trencher, all so that the traction wheels remain firmly on the ground and are not lifted off the ground through the reactive forces created by the trencher boom and its digging chain. A caster wheel is included in the ground wheels and is mounted to be free to caster and to alternatively be restricted relative to the remainder of the trencher for guiding the trencher along a desired line of mobilization.