NC program generating method, NC apparatus, computer memory product, and computer program product

An NC apparatus for performing predetermined machining of a workpiece using an end mill, which determines a tool path of said end mill for said workpiece together with a feed rate in each portion of said tool path, said apparatus comprising:

• machining condition specifying means for specifying machining conditions including a machining start point, a machining end point, and the size of an end mill to be used;
• replacing means for replacing a required machining shape of said workpiece with a predetermined canned machining cycle depending on said machining conditions specified by said machining condition specifying means;
• estimated value calculating means for calculating an estimated value of cutting force exerted on said end mill during said canned machining cycle replaced by said replacing means;
• and
• evaluating means for comparing and evaluating said calculated estimated value with an appropriate value;
• whereby
• a tool path and a feed rate of said end mill is determined by making said estimated value calculating means repeat said calculation of an estimated value until said evaluating means obtains a predetermined evaluation result.

A computer memory product readable by a computer to execute a method for performing predetermined machining of a workpiece using an end mill, which determines a tool path of said end mill for said workpiece together with a feed rate in each portion of said tool path, said computer memory product comprising:

• a first process of replacing a required machining shape of said workpiece with a predetermined canned machining cycle depending on a specification of machining conditions including a machining start point, a machining end point, and the size of an end mill to be used;
• a second process of calculating an estimated value of cutting force exerted on said end mill by assuming a tool path and a feed rate during said replaced canned machining cycle;
• a third process of comparing and evaluating said calculated estimated value with an appropriate value;
• and
• a fourth process of determining a tool path and a feed rate of said end mill by repeating said second process and said third process until a predetermined evaluation result is obtained.

A computer program product for use with NC apparatus, comprising:

• a computer usable storage medium having a computer readable program code embodied therein for performing predetermined machining of a workpiece using an end mill, which determines a tool path of said end mill for said workpiece together with a feed rate in each portion of said tool path, said computer readable program code comprising:
• causing a computer to replace a required machining shape of said workpiece with a predetermined canned machining cycle depending on a specification of machining conditions including a machining start point, a machining end point, and the size of an end mill to be used;
• causing a computer to calculate an estimated value of cutting force exerted on said end mill during said replaced canned machining cycle;
• and
• causing a computer to determine a tool path and a feed rate of said end mill by repeating comparison and evaluation of said calculated estimated value with an appropriate value and calculation of an estimated value until a predetermined evaluation result is obtained.