Put forward two kinds of CNC Machining to be not the new method of round curve outline, make computational difficulty and computational quantity are reduced greatly, already but time of managing process designing, can obtain again approach an error lesserly. Machine tool of economy of current our country numerical control, have linear interpolation and function of circular arc interpolation only commonly, do not have the interpolation function of the Y=f(x) of the curve that be not a circle such as parabola. When accordingly CNC Machining is not the outline of round curve Y=f(x) , must use linear or circular arc paragraph approach. Show some to approach the method of the curve that be not a circle with circular arc, computational difficulty and workload are very big. The article formulates two kinds of new methods, reduced working difficulty, reduced approach an error. Graph the first kind of 11 methods are shown 1 times like the graph, MN is the tangent that bit of A celebrates a festival on Y=f(x) of the curve that be not a circle, make the parallel AB of MN, distance MN is D allow / 2, d allow allows an error for what outline machines, the 1/5 ～ 1/10 that is work measure public errand commonly is advisable. The parallel CD that makes MN is apart from MN to be δ allow, AB and CD hand in the curve that be not a circle to be B and C respectively. The coordinate of the coordinate node B that begs nodical B and C can pass equation series (1) gets: (1) among them K=f(xa) . The coordinate of nodical C can pass equation series (2) gets: (2) among them K=f(xa) . Cross A, B, C to be able to decide a paragraph of circular arc that is less than 180 ° at 3 o'clock, this paragraph of circular arc is round curve of Duan Fei of A, B, C namely approach circular arc. Round equation is: Press above means, a paragraph of terminus that approachs circular arc began to be able to find out sequel once upon a time a series of approaching circular arc. Graph the 2nd kind of 22 methods are shown 2 times like the graph, MN has been the tangent of A of the node on Y=f(x) of the curve that be not a circle, the parallel AB that makes MN is apart from MN to be δ allow, AB is handed in blame, round curve is nodded at B. The parallel AB that crosses B to nod the tangent MN that makes the curve that be not a circle again to make MNq with manage is apart from MN to be δ allow, aqB hands in the curve that be not a circle to be nodded at C. The coordinate of the coordinate node B that begs nodical B and C but group of through type equation (3) gets: (3) among them the coordinate of K=f(xa) nodical C but group of through type equation (4) gets: (4) among them K=f(xb) . Cross A, B, C to be able to decide a paragraph of circular arc that is less than 180 ° at 3 o'clock, this paragraph of circular arc namely of round curve of Duan Fei of A, B, C approach arc. Round equation is: Press above means, a paragraph of terminus that approachs circular arc began to be able to find out sequel once upon a time a series of approaching circular arc. Above of 3 brief summary approachs the method of the curve that be not a circle two kinds with circular arc, apply actually via us, discovery has the following characteristic: Computational difficulty and computational quantity are reduced greatly, managing process designing time. The acquisition length that approachs circular arc varies along with the curvature of contour line and change. Curvature is big circular arc is short, curvature is small circular arc is long, because this does not accept the restriction of size of outline curve curvature. Approach an error to decided round law to want at 3 o'clock than waiting for an error small, but circular arc paragraph number increase. The first kind of method approachs an error than the 2nd kind of method small, but circular arc paragraph amount is much. CNC Milling
CNC Machining