Milling machine clamping apparatus is right dimension of knife piece position is decided really
- source:NEHMER CNC Machining
The keyway of 06mm, assure symmetry 0.
2mm and positional dimension 30-00.
2mm, the graph is shown 2 times pursue to the knife for fixed position, the aperture inside workpiece is 20H70+0.
021mm, arbor is 20h6-0.
007mm, to secure unilateral contact, choose right angle to be opposite knife piece, 1mm of ＝ of S of ply of feet of a place of strategic importance, the computation that determines size of pair of knife piece position is as follows: Graph 1 graph the positional measure that 2 show pair of knife piece with H/2 of H ± δ , the size that the dimension on its correspondence workpiece assures directly to the knife namely indicates with H/2 of H ± δ , here H is the average of the dimension that assures directly to the knife. Inside the limits that the key that seeks a H/2 of H ± δ according to H/2 of H ± δ is the tolerancepublic errand area that should check cutting tool to H/2 of δ of dimension H ± , take δ H ＝ normally (5 ～ of 1 ／ 1 ／ 3) δ H. Line out is right if dimension of knife piece position pursues 2 in H1/2 of H1 ± δ and H2/2 of H2 ± δ , the dimension that goes up according to workpiece gets: H2/2=(30-0 of H2 ± δ .
1) ± 0.
9 ± 0.
H1/2 of δ of ± of H1 of 1mm needs to be gotten through solving dimension catenary, if pursue,3 are shown. H1/2=4 ± of H1 ± δ 0.
07mm takes 4=0 of ／ of H1 of δ of δ H1 ＝ .
4 ＝ of 14 ÷ 0.
4=0 of ／ of H2 of δ of ＝ of 035mm δ H2.
4 ＝ of 2 ÷ 0.
H1/2=4+1 ± of δ of ± of H1 of 05mm reason 0.
± of 035 ／ 2=5 0.
0175mm, (± of H2/2=(H2-S-i2min) of δ of ± of H2 of I1min=0) 0.
=29 of of of of of 05/2 .
2 ± of 007 ／ 0.
=28 of of of of of 025 .
897 ± 0.
025mm still can use a figure additionally 2/2 of ′ of H of 2 ± δ comes to 2 medium H ′ state pair of knife piece are perpendicular directional position, regard fixed position as standard treatment chamfer with A of the generatrix on the aperture inside workpiece right now, right the 2 ± of ′ of positional dimension H of knife piece surface 2/2 of δ H ′ from fixed position the bearing of fiducial A orders the generator on A(arbor) tag case. H ′ 2 by the graph 1 in S of ply of feet of subtractive a place of strategic importance calculates average of dimension of workpiece working procedure. Namely: δ H ′ 2 need to get δ H ′ through solving dimension catenary 2 hind get, (See graph 4) . 2=0 of δ H ′ .
2 ／ of ′ of H of δ of 2= of ′ of 1995 H extraction δ 4=0.
4 of 1995 ÷ 0.
2 ± of ′ of 0499 reason H 2 ′ of δ H ′ 2/2=18.
895 ± 0.
02495mm exemple 2: Graph 5 for workpiece process chart, graph 6 pursue to the knife for fixed position, right the positional dimension of surface of knife piece job by V the standard heart great center of form piece is noted case, right now Imin=0, reason is right the positional dimension H of knife piece end face presses average of working procedure dimension (H-TH/2) and decision of S of ply of feet of a place of strategic importance: Graph 3 graphs because of,H=H-TH/2-S of 4 takes 4 of ／ of 4=TH of ／ of H of δ H= δ 8 graphs of ／ of TH of ± of H/2=H-TH/2-S of δ of this H ± 62 computation of 5 graphs are right the general formula of dimension of knife piece position by above the analysis of two example is calculated, can induce a computation is right the general formula of H/2 of δ of ± of H of dimension of knife piece position is: In type of H/2 of δ of ± of Imin of ± of S of ± of H/2=H of H ± δ : H, fixed position is standard the average that is apart from to what machine the surface; S, ply of feet of a place of strategic importance; Imin, fixed position is standard the volume of the smallest displacement that processing measure respect. When Imin makes machine dimension to increase, take before Imin " - " date; When Imin makes machine dimension to narrow, take before Imin " + " date. δ H, right the public errand of H of dimension of knife piece position, take δ H ＝ normally (5 ～ of 1 ／ 1 ／ 3) δ H, among them the public errand that δ H is dimension H. Clamping apparatus of 3 affirmatory milling machine is right the measure of dimension of knife piece position (1) decides pair of knives are fiducial, line out is right the Hv/2 of δ of ± of positional dimension H of knife piece. (The H/2 of δ of dimension H ± that 2) finds out the workpiece that assures as correspondingly as H/2 of δ of dimension H ± directly to the knife to go up, this dimension is below some circumstances foregone, the need below some circumstances solves dimension catenary to get. (3) reachs δ H ＝ by H/2 of δ of ± of Imin of ± of S of ± of H/2=H of H ± δ (5 ～ of 1 ／ 1 ／ 3) δ H begs a H/2 of H ± δ according to H/2 of H ± δ , inside the limits that assures to be opposite cutting tool to public errand of H/2 of δ of dimension H ± to take thereby. 4 precision desired result uses a level feet of a place of strategic importance and right knife piece is right knife, must make sure W of Δ of position error of DA of pair of knife error Δ , clamping apparatus satisfies δ of ≤ of W of Δ of DA+ of Δ of of inequality / 3 or 3 ability of 2 δ ／ assure ≤ of W of Δ of DA+ of Δ AZ+ Δ finally treatment precision. Among them: Δ AZ -- workpiece mounting error (include J of Δ of error of DW of Δ of fixed position error, clamp; δ -- the public errand of workpiece treatment dimension. CNC Milling CNC Machining