TRACK BALL DEVICE AND ELECTRONIC APPARATUS COMPRISING THE SAME

摘要

Relating to a track ball device for manipulating a cursor moving on a display screen of an electronic apparatus, a track ball device being manipulated precisely while generating a click feel when a ball is rotated, having a small play angle and small size is presented. Beneath the center of the ball, the ball is rotatably supported by four rollers. The section of a contacting portion of the rollers contacting with the ball is a circular sawtooth profile, and the directions of the sawtooth serrations of opposite rollers are reverse to each other. Rollers 2 to 5 have switches as rotation amount detecting units. Further, X roller and Y roller contacting with the outer circumference in the orthogonal direction as seen from above the ball, and third roller hold the ball rotatably. Plural undulations are formed on the outer circumference of large-diameter contacting portions of the X roller and Y roller 3 of circular shaft shape. Rotary encoders are coupled to individual rollers.