The actual inventor【主语】//  is 【系动词】// almost invariably【状语】//  the man 【表语】// who succeeds in combining and perfecting previous discoveries in such a way as to make them convenient and profitable【定语从句】// . 

以下是由关系代词who引导的限制性定语从句的语法结构分析供网友参考

who 【主语】// succeeds【谓语动词】 in combining and perfecting previous discoveries 【方面状语】in such a way as to make them convenient and profitable【方式状语】// . 

备注：关系代词who指代先行词the man并在定语从句作主语。succeed in doing sth 成功做成某事。in such a way 以这样一种方式。make sth convenient and profitable 使某事方便且有利。