Ключевые слова: abstract, background, cog, concept, connect, connection, design, drive gear, energy, engine, engineering, equipment, factory, gear, gear wheel, gearing, illustration, industrial, industry, involute, machine part, machine tool, machinery, mechanic, mechanical, mechanism, metal, module, movement, old, part, power, repair, screensaver, service, steel, technical, technology, teeth, template, texture, tool, transportation, vehicle, wheel, work, work of mechanisms,