Patent ID: 7001139
Filing Date: 2006-02-21
Classification: B25J,Y10S,Y10T

Abstract:
1. A robot arm mechanism comprising: a first arm link mechanism consisting of a first quadric crank chain comprising a first arm link, a second arm link substantially in parallel relationship with said first arm link, a third arm link, and a fourth arm link substantially in parallel relationship with said third arm link; a second arm link mechanism consisting of a second quadric crank chain comprising a first arm link, a second arm link substantially in parallel relationship with said first arm link, a third arm link, and a fourth arm link substantially in parallel relationship with said third arm link, said third arm link of said second arm link mechanism being fixedly connected with said third arm link of said first arm link mechanism, said second arm link mechanism is pivotably connected with said first arm link mechanism; a link retaining mechanism having a reference line, said link retaining mechanism pivotably retaining said first arm link mechanism and said second arm link mechanism respectively and keeping a first angle substantially equal to a second angle, said first angle being an angle formed by a line passing through said first arm link of said first arm link mechanism with said reference line, said second angle being an angle formed by a line passing through said first arm link of said second arm link mechanism with said reference line; a robot arm driving mechanism comprising; a first driving shaft operative to rotate said first arm link of said first arm link mechanism around a rotation axis in any one of two rotation directions consisting of a first rotation direction in which said first arm link mechanism and said second arm link mechanism are extended, and a second rotation direction in which said first arm link mechanism and said second arm link mechanism are contracted; and a handling member for supporting and handling an object, connected with said second arm link mechanism, whereby said robot arm driving mechanism is operative to rotate said first arm link of said first arm link mechanism around said rotation axis in said first rotation direction, and said fourth arm link of said first arm link mechanism around said rotation axis in any one of two directions consisting of said first rotation direction and said second rotation direction while maintaining said first angle formed by a line passing through said first arm link of said first arm link mechanism with said reference line less than a third angle formed to be less than 180 degrees by a line passing through said fourth arm link of said first arm link mechanism with said reference line in said first rotation direction.