In an industrial robot of a type having an arm made of a pentagonally connected links, of which an uppermost link is secured to a stationary member so as to be swingable around its axis, the uppermost link is rotated by a first motor, while second and third motors are provided nearby the uppermost link...http://www.google.fr/patents/US4730975?utm_source=gb-gplus-shareBrevet US4730975 - Industrial robot
