The fixed position on machining center decides fiducially
- source:LENA CNC Machining
Machining center has working procedure to wait for an advantage centrally, go up objectively ask place choosing fixed position is standard should satisfy as far as possible " hold clip, all (or major) machine " , before be being machined so very be necessary to choose location seriously fiducial, in order to produce the advantage of machining center, reduce the number that hold clip, improve product quality, reduce manufacturing cost. A few typical parts combine below, how does preliminary analysis decide on machining center its fixed position is standard. 1, typical the affirmatory with a standard fixed position 1.
1 cuboid some pattern that shows 1 times like the graph core, 3 faces need to machine (underside, left side and on the surface) , its issue makings dimension to be × of 261 Mm of × of 281 Mm 331 Mm (curiums cut next material, unilateral stays each about 0.
5 Mm surplus, each surface surface roughness is basic consistent) . This appearance suits to use means of 3 planar fixed position, so, what face to choose to make fixed position fiducial? Which face decides fiducial? Analyse treatment craft above all, can you divide for 3 strides: ? The rough machining before?1) heat treatment reachs local finish machining, need to hold clip 3 times on machining center of 3 axes vertical (if choosing four-axle horizontal machining center, can installing clip to finish full treatment; is underside only cooling when deep aperture treatment effect what go up in vertical machining center not as good as is good) ; ( of of; of 2) heat treatment (3) finish machining includes left, among them the finish machining of old plane can be arranged go up in grinder, the electric spark of appropriate of difficult milling area such as local and narrow groove is machined, the others still has precision work on machining center. Graph selection of 1 mould core is wide fiducial when, the key considers how to assure to machine a face to be able to allocate reasonable mental allowance individually, assure to machine face and the positional dimension that do not machine a face and positional precision, offer reliable choice for follow-up working procedure even at the same time fiducial. Does choice plane make: of Lv of fiducial and general take an examination? ?1) oneself locates ability loses by force, basically include: The level of face region size, level, surface roughness, difficulty that hold clip, stable rate (not changeful form, endurance) the planar and first consideration that waits for; area to jump over big, surface roughness to jump over clip of low, outfit to go to the lavatory more. (Locate ability loses by force related 2) , advocate the influence degree that if point to,concerns to dimension public errand and to fiducial principle reflect rate. Make fixed position standard as far as possible as fiducial as the design, measure fiducial unite with process designing origin rise. On the base that considers afore-mentioned factors integratedly, when the primary and secondary that fixes 3 datum plane concerns, still should avoid main fixed position as far as possible fiducial with wait for treatment face to be the same as azimuth, arrange its power of can effective opposite what treat treatment range counteractive cutting, also be helpful for simplifying clamping apparatus structure. Choose the 2nd location Lv of fiducial take an examination its are oriented action, with advocate the verticality with standard fixed position, surface roughness, and the place that needs treatment range together affects. In the 3 paces that machine afore-mentioned moulds core, each pace is existing to decide fiducial issue, and so much working procedure, certainly will should be united fiducial. Going up as a result of main appearance the surface, reason and its corresponding underside appropriate decide fiducial. Additional, the region of two lateral faces that makes bit of F is bigger, good; of the effect that prop up but see those who devise measure tag a circumstance again, on 3 ranges that make bit of O dimension is tagged much, but viewpoint O is a design fiducial, at the same time its face region is used propping up also is possible, reason the angle from fiducial coincide, the fixed position before choosing 3 ranges that make bit of O to make heat treatment is standard. There is a center only on blueprint of a mould normally, the dimension of each component is rolled out from this. Machine some specific component when, go up in this specific feature, line, face establish is fiducial, basis dimension concerns, building coordinate is. If 3 faces mutual very not perpendicular (usually, semifinished product short of this requirement) , can machining underside (machine underside first normally) when, give priority to with underside fiducial, on additionally two flank, according to need, respectively the fiducial area that mill gives certain length is used for follow-up treatment, assure fiducial and unified, if pursue,2 are shown. Graph 2 model fixed position of core semifinished product is standard afore-mentioned fixed position are standard in the treatment process that is used before heat treatment. After heat treatment, must detect this deformation of fiducial oneself, and shape face photograph is old to be out of shape because be out of shape,; can appear occasionally fiducially and cannot serve as again fiducial used case. Accordingly, before heat treatment, should consider and the finish machining fixed position with more reliable obligate is standard. When alternative energy is fiducial, what consider mainly is the fixed position error that how reduces workpiece, assure the treatment precision of the spare parts, also should consider a spare parts to assemble and unassemble at the same time convenient, clamping apparatus structure is simple. Should follow the following principle commonly: Fiducial and fiducial coincide, unified, it is for fiducial, each other oneself fiducial reach outfit clip to go to the lavatory etc. This is medium, aperture of 8 Mm passes reamer precision work, exterior quality is good, cause because of heat treatment be out of shape lesser also, can serve as finish machining fiducial with. A kind of when this wants respecting subsequently namely more typical method -- the rough sketch that uses aperture or rod (central line) make fixed position fiducial. What above says is the sheet that is a delegate with mould core production. Cuboid when batch is produced, should use clamping apparatus to secure the position of 3 datum plane normally come down, in order to improve efficiency. Such example is very common, in article no longer give uncecessary details. But those who be like the cuboid work that the graph shows 3 times is fiducial and affirmatory, a little some are special. This form is not complex, outstanding characteristic is dimension public errand the demand is very little (± 0.
01 Mm) . Belong to supplied materials treatment, its issue makings dimension to be × 51 Mm of 45 Mm of × of 76 Mm, to reduce the number that hold clip, the fixed position that produces way of lieutenant general length piece used mobile gauge block, outfit clip (show 4 times like the graph) when fixed position, carry away after outfit clip is good, place next treatment to be over in outfit so two end panel and end face, realized working procedure concentration is the biggest change, decreased to hold clip number, produced the advantage of machining center adequately, also assured (75 ± 0.
The dimension such as 01) Mm asks. Because machine direction of the length in the process to go up nonexistent fixed position, belong to; of not complete fixed position to machine the effect actually nevertheless so not bad, almost rarely assemble is moved. About this treatment, will introduce technically subsequently. Graph 3 slide block pursue outfit of 4 slide block places sketch map 1.
2 swing tower swing tower fixed position is standard choose its normally inside (outside) the surface. Basic method is: Use the syringe needle of dial gauge (or of photoelectricity inductor touch first class) , the edge measures the center that gives 4 to nod to be central line position namely crisscross, detailed sees a picture 5. Specific when measuring, should of preexistence aperture upper part 2 -- 3mm place rotates watch needle, make syringe needle is being measured roughly the side outside bore diameter (axial word, answer deflection inside) , press what watch needle makes gently to enter hole next inside, find out the semmetry on some direction above all at 2 o'clock (if nod A and C or as parallel as AC line some locally at 2 o'clock) symmetrical center, hereinto heart line (CD line) during the divide into equal parts that goes up to look for C and bit of D again nods O (, need adjusts syringe needle position) , a week rotates again after finding out, examine watch needle jumpy circumstance, whether does the AC line that a moment ago fixed in order to check pass bit of O, the machine tool coordinate that finds out O of the centre of a circle finally thereby (rotate a week, the fall asleep that express a needle or slight quiver) . Should notice in certain course, does the fall asleep that express a needle have 3 to plant likelihood: ? ?1) was not contacted inside of exterior; (2) and inside the pressure between the surface is too great and cannot beat; (3) main shaft is in position of the centre of a circle. Because of final record is position of the centre of a circle, inspect axes to be fixed position fiducial also have not cannot. Close document to consider to prove both does not have substantial difference. Graph 5 swing tower fiducial aperture searchs of Z direction fiducial but the surface on first consideration. Give priority to as to which fiducial, should combine mental allowance and exterior surface roughness to decide. Normally, it is the spare parts of main feature with swing tower, inside (outside) fixed position effect of the surface is a few mainer, because it often can be a design fiducial, impact of dimension public errand is much, eye of limitative workpiece number of degrees of freedom is much. As a result of lever dial gauge and the top that workpiece contacts the diameter is 3 Mm, want bore diameter to be more than 6 Mm only so, when can using; to be less than 6 Mm, can consider to insert arbor, measure external diameter. Choosing through CAPP system when fixed position is standard, to ensure correct and decision-making with treatment precision, these influencing factor also should be considered. Manage together, make with keyway when fixed position is standard, because gauge block is OK,a place of strategic importance goes in, so theoretic, the fixed position that the keyway of above of width 1 Mm is a likelihood is standard, using CAPP system to choose when fixed position is standard, also do not answer by oversight. 1.
3 abnormity if be lacked on workpiece,can regard fixed position as fiducial appropriate surface, be necessary to make a few datum plane artificially, make its have fixed position effect in treatment, this kind fiducial call auxiliary and fiducial. Graph 6 for some product sketch map, batch production, besides " shape face " besides the part, 5 faces all are the others coordinate a side, need precision work, precision demand is high, shape at the same time clip cannot be held on the face. It how should hold clip, fixed position so is good to how should hold clip, fixed position so? Observe product figure can discover carefully, by R 1, R 2, the circular arc surface that R forms 3 times and the fluctuation range that make dimension 70 Mm are potential fixed position fiducial option. Through the analysis, decided R finally 1, R 3 and on the fixed position that plane is different process respectively is standard, but only this is unwarrantable still the exact location of each working procedure and outfit clip.
In do not hamper used premise falls, craft opening increases on primary product figure: M8 whorl increases in end face, overleaf increases 10H7 of of ministry of mouth of M8 (of 3 × deep 8 Mm makes fixed position use) , reason revises a product to if the graph is shown 7 times,pursue. On this foundation, design then cast semifinished product picture, these 3 go up to increase A of datum plane of auxiliary fixed position, B and C (again in cast fiducial belong to add capable person, use hind take out) . Graph 6 some abnormity product figure pursues the 7 abnormity that take workpiece art aperture product figure pursues 8 abnormity the place before semifinished product graph is like is narrated, these are fiducial use in different process respectively, how should fiducial and unified principle assure? Settling way is: Use machining center to machine precision tall and the dominant position that working procedure amasses, be in as far as possible in outfit clip all fixed position that can machine fiducial machine come out; really of short duration cannot machine, machine auxiliary fixed position for its fiducial. From effective treatment the result looks, these fixed position assured product quality effectively. These are auxiliary and fiducial action is lost after treatment, belong to the word that adds capable person, after the event can be decreased by take out; normally material kind (like craft aperture) do not affect a product to use commonly, withhold. From on the exemple is OK see: The abnormity that produces to batch, be in affirmatory and fiducial when, answer to combine treatment technology cheek by jowl, make full use of the idea that has the; such as the plane on appearance and circular arc face to repass adds capable person or reduce ability when necessary, increase auxiliary fixed position fiducial, assure product quality thereby. Machining center of 2, last word has efficiency of working procedure concentration, production to be mixed high treatment quality is good wait for an advantage, when location of certain on machining center work is fiducial, how does Lv of take an examination produce the advantage of machining center adequately, those who realize product treatment is high quality and efficient. Be opposite in article cuboid, swing tower with abnormity fixed position is standard the analysis of the choice, although specific method is different, but guiding ideology is consistent: Buckle the treatment feature of the product closely, pay attention to the dominant position that develops machining center adequately, seek efficient and high grade treatment course. Nevertheless, the affirmatory method with standard fixed position just went up to do a preliminary summary to machining center in article, not quite comprehensive still, still a lot of circumstances need farther henceforth summary, abstraction. Origin: Project of Electromechanical of institute of Henan profession technology is, institute of Electromechanical of university of industry of Henan Zhengzhou northwest, institute of machinery of university of water and electricity of China north irrigation works CNC Milling