| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power transmission apparatus for a machine tool of a simple structure eliminating the use of a clutch.SOLUTION: A chuck 3 or a facing unit 37 is provided at the front end side of a hollow main spindle 1, a main spindle rotary body 5 co-rotating with the main spindle 1 is provided at a rear end side of the main spindle 1, a main spindle side gear mechanism 4 transmitting the rotation of the main spindle rotary body 5 to a power transmission output shaft 21 is combined with a power transmission side gear mechanism 11 transmitting the rotation of an input shaft 17 connected to an electric motor 10 side to the power transmission output shaft 21 via a planetary gear mechanism; a gear ratio of each of the gear mechanisms is set in such a manner that the rotation of the power transmission output shaft 21 becomes the same rotation of the main spindle rotary body 5 in a rotation-stopped state of the input shaft 17, the relative rotation of the main spindle 1 to the power transmission output shaft 21 is enabled, axes of the input shaft 17, the power transmission output shaft 21 and the main spindle rotary body 5 are set on a same line, the power transmission output shaft 21 is connected to a transmission shaft 23, and the power is transmitted to the chuck 3 or the facing unit 37 via the transmission shaft 23. |
