Exceed the impact of speed of accurate and planar abrade treatment to precision

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The lens face of 02 μ M. The silicon of such as gauge block, optical plane, integrated circuit base piece wait for hard clear part, finally is to use exceed nicety abrade the high quality surface that receives a demand with polishing. Its key is how to raise precision of efficiency, treatment, reduce cost. Use those who exceed atomic diamond emery wheel is perpendicular those who decorate exceed accurate and planar abrade method 8, can satisfy afore-mentioned need. Its structure is shown 1 times like the graph. Planar and abrade as a result of abrade annulus with workpiece surface contact, the effective cutting number that wears bead is more, can gain tall exterior precision and treatment efficiency. In the meantime, to improve position of cooling fluid job, reduce the effect that machines dynamic pressure, grind now ground round of majority to use construction of type opening slot to design 2 9. Basically have: Radiation groove structure and structure of corkscrewed yarn groove two kinds of forms. Be aimed at afore-mentioned abrade methods, the article undertakes comprehensive analysis to this treatment parameter of abrade process, reach atomic diamond is abrade annulus different groove structure and treatment rate change are right the influence that machines face precision, and from theoretic solve plane abrade in the option issue of parameter of emery wheel treatment. 1 planar and abrade principle pursues 1 to exceed the structural diagram with accurate abrade plane. Machine tool emery wheel and workpiece main shaft use gas fluid to mix bearing to remove the oscillatory effect in treatment, workpiece uses adhesive bonding or true suction force is secured go up in special fixture; Workpiece main shaft relies on bedspring to prop up go up in the machine tool, the adjustable length that controls bedspring can realize the constant voltage treatment to workpiece. The nap that online nap orgnaization can realize to use emery wheel to treatment is shut 1. Principle of planar and abrade treatment is shown 2 times like the graph. For convenient analysis, the set in the graph: M is emery wheel on a bit; N is a bit what be gotten on by treatment workpiece, if what the basic parameter of emery wheel and workpiece shows in the graph. By the graph 2 movement that show emery wheel and work concern, the θ in alternating through coordinate the M on attainable emery wheel nods the treatment contrail equation on workpiece to be type, emery wheel machines initiative horn ω 1, the angular velocity ω of workpiece 2, the angular velocity α of emery wheel, the center of emery wheel and workpiece is apart from R, the radius of dot of the M on emery wheel, coordinate fastens X ' O2y ' produce on radius nods the slippage contrail equation on emery wheel to be the φ in type for the N of R, workpiece machines initiative horn ω 1, the angular velocity ω of workpiece 2, the angular velocity α of abrade emery wheel, the center of abrade emery wheel and workpiece is apart from R: The M on emery wheel nods the LM of cutting contrail length on workpiece (on emery wheel grind bead to wear away) in be type, φ M φ - M -- the LN of significant slippage length that the emery wheel of angle of cut of the week outside the cutting contrail that the M on emery wheel nods and workpiece nods in the N on workpiece is 2.

Equation of radiation of emery wheel of 1 radiation emery wheel can write the N in be type, the significant slippage length of emery wheel of radiation of radiative lines number is emery wheel I of the β in type, the nodical β of upside of emery wheel radiation and trochoid - I, the node of bottom of emery wheel radiation and trochoid 2.

Equation of corkscrewed yarn of emery wheel of emery wheel of 2 corkscrewed yarn can express to be the γ in type, T of coefficient of emery wheel corkscrewed yarn, width of emery wheel corkscrewed yarn can solve the nodical coordinate that gets trochoid and emery wheel corkscrewed yarn, I of the α in getting the significant slippage length of corkscrewed yarn emery wheel is type from this, the nodical α of upside of emery wheel corkscrewed yarn and trochoid - I, the nodical α of bottom of emery wheel corkscrewed yarn and trochoid 1... α J, nodical coordinate J, nodical number uses a list the parameter of emery wheel structure of 1, adopt formula (4) , (6) and (8) the significant slippage length that can get planar, corkscrewed yarn and radiation structure emery wheel respectively. Convey different structure to facilitate at the same time abrade annulus treatment precision 1, introduce the idea that machines precision coefficient L(r) first. The Ln in type, the L0 of significant slippage length that the N on workpiece nods, the significant slippage length of work center by formula (3) the effective cutting length that can get dot of emery wheel M to go up in workpiece with watch L. Same, to facilitate expression differs the structure is abrade annulus wear away 2, fetching emery wheel wears away coefficient K(R) concept. The LM in type, the LK of effective cutting length that the M on workpiece nods, the influence of change of 3 opposite angular velocity to abrade treatment machines the effective cutting length of planar emery wheel in, because acceleration reachs the influence that machines load change, and the influence of parameter of simple structure of the dynamic pressure that machines cooling fluid and workpiece material, abrade round of angular velocity with workpiece cannot assure to agree, abrade annulus with there is angular velocity to differ △ ω between workpiece. Be aimed at radiation now abrade annulus with corkscrewed yarn abrade annulus, research is abrade in emery wheel and workpiece angular velocity are unequal (1 ≠ of ω ω 2) when, the L(r of treatment precision coefficient that the angular velocity of abrade emery wheel and workpiece differs pair of emery wheel) and wear away coefficient K(R) influence. For convenient research, the article assumes θ =0 ° , φ =0 ° , ω =400r/min is changeless, 2 change of ω . Two kinds of structures are abrade if round of structure parameter expresses L place to show. Nextpage3.

The influence of change of 1 opposite angular velocity to machining precision pursues the 3 ω that it is △ (ω of 2- of ω of △ ω = 1) when taking different cost, workpiece is in the significant slippage length on emery wheel. Line of 3 trends in the graph represents △ ω =-20r/min respectively, 0 R/min of △ ω ＝ , △ ω ＝ the circumstance of 20 R/min. Can see from inside the graph: Abrade to radiation annulus, when O of △ ω ＞ , workpiece is in the significant slippage length on emery wheel is the longest; When △ ω =0, take second place; When O of △ ω ＜ , workpiece is in the significant slippage length on emery wheel is the shortest. And abrade to corkscrewed yarn annulus, the change of △ ω is not apparent to the influence of significant slippage length. By formula (9) can get △ ω (ω of 2- of ω of △ ω = 1) when taking different cost, the treatment precision coefficient of different structure emery wheel is shown 4 times like the graph, line of 3 trends in the graph represents △ ω =-20r/min respectively, 0r/min of △ ω ＝ , △ ω ＝ the circumstance of 20 R/min. Length of significant on emery wheel slippage has treatment precision coefficient and workpiece to concern directly, to radiation emery wheel, treatment precision coefficient increases along with what angular velocity differs and increase; And to corkscrewed yarn emery wheel, treatment precision increases along with angular velocity, change is not big. 3.

2 photographs are right to angular velocity change abrade round of tatty influence graph 5 for radiation and ω of △ of corkscrewed yarn emery wheel (ω of 2- of ω of △ ω = 1) when taking different cost, emery wheel is in the effective cutting length on workpiece. Line of 3 trends in the graph represents △ ω =-20r/min respectively, 0r/min of △ ω ＝ , △ ω ＝ the circumstance of 20 R/min. If plan institute is shown, different to two kinds structure is abrade annulus, as the addition with poor angular velocity, the effective cutting length on workpiece also increases. By formula (10) can get △ ω (ω of 2- of ω of △ ω = 1) when taking different cost, of radiation and corkscrewed yarn emery wheel wear away coefficient is shown 6 times like the graph, line of 3 trends in the graph represents △ ω =-20r/min respectively, 0r/min of △ ω ＝ , △ ω ＝ the circumstance of 20 R/min. △ ω increases, wear away coefficient increases, namely abrade annulus wear away increase. Also can see, the wear curve it may not be a bad idea of itself of radiation emery wheel at corkscrewed yarn emery wheel. The article passes 4 conclusion build plane abrade in abrade model of round of opposite motion maths with workpiece, the cutting contrail that gets emery wheel went up in workpiece reachs the on workpiece a bit slippage orbit on emery wheel. Analysed different structure abrade emery wheel and its and workpiece are mixed relative to angular velocity and workpiece precision coefficient emery wheel wears away the relation between coefficient. Study the result makes clear: (1) is abrade to radiation emery wheel, be worth as the difference of angular velocity of abrade emery wheel and workpiece angular velocity to increase, treatment precision rises; And corresponding ground, increase reversely as the poor value of angular velocity of abrade emery wheel and workpiece angular velocity, machine precision general subsequently and reduce. And abrade to corkscrewed yarn emery wheel, treatment precision changes an effect along with opposite angular velocity not quite. (2) is abrade to radiation emery wheel and corkscrewed yarn are abrade emery wheel, be worth as the difference of angular velocity of abrade emery wheel and workpiece angular velocity to increase, of abrade emery wheel wear away increase, this treatment precision accordingly exasperate workpiece. From reduce emery wheel to wear away, the angle that raises emery wheel utilization rate sets out, answer to reduce the poor cost of angular velocity of abrade emery wheel and workpiece angular velocity as far as possible, or increase what make reversely. (3) machines parameter through logical choice, control the bulk of opposite angular velocity namely, can get first-rate machines precision curve, obtain ideal emery wheel wear curve at the same time, effectively implementation treatment precision is tall, abrade the end with round of long life. CNC Milling