Abstract: End-mill machining control method and apparatus in which cutting forces tangential and normal to tool motion are detected and machining is controlled based on the detected cutting force values. A primary component Ft and motion axis components Fx, Fy of a cutting force are determined from current values of a spindle motor and motion axis motors for tool feed. A cutting-engaged angle ?en is determined from a radius R of a tool and a depth of cut I into a workpiece. A motion direction angle ? is determined from distribution motion amounts ?X, ?Y to the axes. The cutting forces Fm, Fs tangential and normal to tool motion are determined from the primary component Ft and a motion axis component Fx or Fy whichever is the largest, the cutting-engaged angle ?en, the motion direction angle ?. The accuracy of the determined cutting forces Fm, Fs is high since they are determined from the primary component Ft less affected by disturbance and the largest axis component of the cutting force.

Abstract: An NC apparatus 1 replaces a required machining shape of a workpiece 5 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 E to be used. Calculation of an estimated value of cutting force exerted on the end mill E fed along the assumed tool path during the replaced canned machining cycle is repeated until a predetermined comparison and evaluation result is obtained in comparison with a predetermined appropriate value. Accordingly, the tool path of the end mill E together with the feed rate in each portion of the tool path is determined. This permits generation of an NC program which is used in a NC machine equipped with an end mill serve as a cutting tool, and which optimizes the tool path of the end mill together with the feed rate in each portion of the tool path such as to achieve high machining efficiency and accuracy.

Abstract: End-mill machining control method and apparatus in which cutting forces tangential and normal to tool motion are detected and machining is controlled based on the detected cutting force values. A primary component Ft and motion axis components Fx, Fy of a cutting force are determined from current values of a spindle motor and motion axis motors for tool feed. A cutting-engaged angle &agr;en is determined from a radius R of a tool and a depth of cut I into a workpiece. A motion direction angle &bgr; is determined from distribution motion amounts &Dgr;X, &Dgr;Y to the axes. The cutting forces Fm, Fs tangential and normal to tool motion are determined from the primary component Ft and a motion axis component Fx or Fy whichever is the largest, the cutting-engaged angle &agr;en, the motion direction angle &bgr;. The accuracy of the determined cutting forces Fm, Fs is high since they are determined from the primary component Ft less affected by disturbance and the largest axis component of the cutting force.

Abstract: A maximum undeformed chip thickness, a cutting arc length or an engage angle, and an active angle for each tooth of the end mill are calculated when a ball end mill is used in machining, or the maximum undeformed chip thickness, the cutting arc length or the engage angle, and an axial depth of cut for each tooth of the end mill are calculated when a straight end mill is used in machining. Then, the estimated value of the cutting force Fxy or Fxyz in each portion of the tool path is calculated on the basis of a response surface whose explanation variables are composed of the above-mentioned calculated values, whereby the feed rate contained in an equation for the maximum undeformed chip thickness tm is determined to maintain the obtained estimated value of the cutting force Fxy or Fxyz at an appropriate value.

Abstract: An NC apparatus 1 replaces a required machining shape of a workpiece 5 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 E to be used. Calculation of an estimated value of cutting force exerted on the end mill E fed along the assumed tool path during the replaced canned machining cycle is repeated until a predetermined comparison and evaluation result is obtained in comparison with a predetermined appropriate value. Accordingly, the tool path of the end mill E together with the feed rate in each portion of the tool path is determined. This permits generation of an NC program which is used in a NC machine equipped with an end mill serve as a cutting tool, and which optimizes the tool path of the end mill together with the feed rate in each portion of the tool path such as to achieve high machining efficiency and accuracy.

Abstract: A maximum undeformed chip thickness, a cutting arc length or an engage angle, and an active angle for each tooth of the end mill are calculated when a ball end mill is used in machining, or the maximum undeformed chip thickness, the cutting arc length or the engage angle, and an axial depth of cut for each tooth of the end mill are calculated when a straight end mill is used in machining. Then, the estimated value of the cutting force Fxy or Fxyz in each portion of the tool path is calculated on the basis of a response surface whose explanation variables are composed of the above-mentioned calculated values, whereby the feed rate contained in an equation for the maximum undeformed chip thickness tm is determined to maintain the obtained estimated value of the cutting force Fxy or Fxyz at an appropriate value.