Patent ID: 8009064

Claim:
A data input device for a portable terminal having a main body, the device comprising: a rotation body enclosed by upper and lower cases in such a manner that a portion of the rotation body is exposed to the outside of the main body and moves when the rotation body is rotated or pressed; a holding unit for maintaining a stopped state of the rotation body, the holding unit being connected with the rotation body; a first switch unit for inputting data as a result of a rotating operation of the rotation body, the first switch unit being in contact with the rotation body; an elastic sliding unit linked with the holding unit for moving along with the holding unit to guide the movement direction of the holding unit when the rotation body is pressed, and returning the rotation body and the holding unit to their initial positions; and a second switch unit for inputting data when the rotation body is pressed, wherein the holding unit comprises a serrated belt pulley in contact with an interior of the rotation body to move along with the rotation body depending on movement of the rotation body and having multiple openings formed in an upper surface of the serrated belt pulley at equal intervals along an outer peripheral surface of the serrated belt pulley; at least one spring module in contact with the serrated belt pulley while being parallel to the serrated belt pulley's axis of rotation and opposed to the openings, said at least one spring module being coupled with one of the openings to maintain a stopped state of the rotation body at a certain interval.