Abstract: For superfinishing an elongate cutting tool which has been rough-ground by a separate machine, a pair of grinding wheels are first urged against the opposite sides of the work via respective fluid-actuated cylinders, until sufficient fluid energy builds up in the cylinders to enable the grinding wheels to grind the work to any desired depths. Being mounted on a common carriage, the grinding wheels are then reciprocated longitudinally of the work while being held in constant rotation and being urged against the work under the fluid pressure. On reaching either end of the work during such reciprocation, the grinding wheels are relieved of the fluid pressure until they restart traveling toward the other end, in order to avoid overgrinding the opposite ends of the work. The reciprocation of the grinding wheels is terminated when the opposite sides of the work are ground to required degrees. The complete operation can be automated.

Abstract: A power generation cassette type power plant for marine electric propulsion includes a multiplicity of power generation units each being formed as a power generation cassette including a power generator, a prime mover, for example an internal combustion engine for driving the power generator and a support structure for supporting the power generator and the engine internally. The support structure is formed in the same shape as that of a container for transporting cargo. When the power generators of the multiplicity of power generation units are operated in parallel to each other to supply electric power to a load, controllers serve to share the load to the generators properly.