Abstract: A numerical control apparatus for controlling a machine having two moving shafts placed in parallel and separate servomotors 6 and 10 for driving one of the shafts as a master shaft and the other as a slave shaft in the same direction and performing return to origin of the above-mentioned master shaft and the slave shaft according to a dog technique. The numerical control apparatus comprises position determination module determining the positional relationship as to whether or not the master shaft is ahead of the slave shaft, and return-to-origin management module performing return to origin of the master shaft and the slave shaft with one dog based on the determined positional relationship, so that the return to origin of the master shaft and the slave shaft can be performed with one dog. Moreover, the return to origin can be performed reliably at parallel positions.

Abstract: A numerical control apparatus for controlling a machine having two moving shafts placed in parallel and separate servomotors 6 and 10 for driving one of the shafts as a master shaft and the other as a slave shaft in the same direction and performing return to origin of the above-mentioned master shaft and the slave shaft according to a dog technique. The numerical control apparatus comprises position determination means 16 for determining the positional relationship as to whether or not the master shaft is ahead of the slave shaft, and return-to-origin management means 14 for performing return to origin of the above-mentioned master shaft and the slave shaft with one dog based on the determination result of the position determination means, so that the return to origin of the master shaft and the slave shaft can be performed with one dog and moreover the return to origin can be performed reliably at parallel positions.