Numerical control device

A numerical control device having a function of preventing machine collision, the numerical control device comprising:

• a collision determining unit that detects a possibility of collision between a machine and an area set as an entry prohibited area;
• an operation-continuation instructing unit that instructs whether to continue an operation when the collision determining unit detects the possibility of collision and shaft movement is temporarily stopped;
• a machining-information storage unit that stores internal operation information of the numerical control device regarding the temporary stop when the operation-continuation instructing unit instructs continuation of the operation;
• and
• a collision-determination processing unit that invalidates a collision determination on the basis of the operation information stored in the machining-information storage unit when executing the same machining program the next and subsequent times,
• a collision-determination invalidation command for invalidating a collision determination of a corresponding program row of the machining program in which the possibility of machine collision has been detected;
• or
• any one of a kind of interference check, current position coordinates of each shaft and original point information, which includes at least a machining-program row number of a corresponding program row of the machining program in which the possibility of machine collision has been detected.