Machining center is in machine the promotion that measures pair of working procedure quality

1 be in machine the composition that surveys a system is carried out in machine measure basically measure receiver of head, signal and output cable by contact in aircraft capacity appearance (or interface device) composition, according to the property of deferent signal, divide again wait for 2 kinds for infrared ray and radio. Under photograph comparing, a kind signal conveys after capability is some stronger, not only deferent space is large, insusceptible also below the circumstance that is held back by the object. The graph gave out the composition of a kind of typical system and working process: Contact measures a head detect the result sends installation with infra-red signal means the receiver inside machining center, receiver passes output cable (or course interface device) convey signal to control a system to the machine tool. Current, detect software part two kinds: By what offer in manufacturer of aircraft capacity instrument comprehensive and three-dimensional metric in machine measure software, by in manufacturer of aircraft capacity instrument or the simple one dimension that machine tool manufacturer has woven by effective demand or feature of 2 dimension geometry measure grand form. At present a lot of users use latter and auxiliary treatment, have all-pervading tendency. 1.

2 main functions measure a head in the contact of aircraft capacity appearance, metrical object can be workpiece, clamping apparatus, also can be cutting tool, come completely according to the need of different user. Design and carry out corresponding function. Should detect the object is workpiece and clamping apparatus when, will use a graph to measure a head mediumly 1. Right now, contact measures a head to be just like cutting tool same, in depositing the knife library in machining center at ordinary times, the demand with diverse according to, before machining working procedure together or later v, carry out by the program again detect automatically, realize some kind of function thereby. And should detect the object is cutting tool, adopt a plan 1 measure a head mediumly 2 (also call pair of Dao Yi) , at this moment " type " measure a head to be secured to be on the mesa of machine tool job of machining center. Say wraparoundly, be in through be in what aircraft capacity appearance carries out machine measure, basically can achieve the following goal: Of cutting tool condition detect of pair of cutting tool condition detect also call " to the knife " , refer to a graph 2. Right now, it is the measurement unit that uses a setting to go up in mesa of machine tool job (to Dao Yi) , to knife library medium cutting tool is pressed beforehand the program of set undertakes the knife is measured is opposite, make judgement is made after comparing with fixed cost next. In the meantime, pass pair of cutting tool detect also can come true to wear away to cutting tool, damaged or installation model are correct identify. Graph 2 it is a few give typical examples that measure to the knife: A: What having cutting tool is long (tall) degree detect, b: Measuring in what have way of cutting tool radius, c: Wait for detected cutting tool right now already damaged, through measure can seasonable discovery and calling the police to the knife. Use pair of Dao Yi to make be opposite inside machine knife, not only managing be opposite outside machine the manpower when the knife, material resources, improved work efficiency, and located to the knife environment and treatment status are consistent, can reduce the effect that brings by cutting tool clamping force and temperature change to the greastest extent. In " cutting tool condition detects " circumstance of this kind of application, detect what signal uses is before narrate cable device of interface of deferent means input, or join with system of machine tool numerical control directly. To the knife measurement unit has contact and blame contact (optical) type two kinds, graph the 2 give typical examples that are more commonly used contact. The set of parameter of machine tool treatment is passed in aircraft capacity appearance in machine measure, indirect or get machining center forthrightly the most appropriate when carrying out next line working procedure treatment parameter, can improve the production quality of workpiece greatly thereby. This kind have specific aim, the circumstance application that the working way that intelligence changes is in those having to cooperate relation or special requirement is more, if take the plane on the cylinder body of cylinder bushing,treatment, crock covers the situation such as the treatment of combustion face. Ensure true treatment condition: Of workpiece, clamping apparatus search to be being mixed compensation is so-called " search " , it is to point to takes to assure the correct installation of workpiece, fixed position corresponding step. As to existence " frame-up " , have the reason of clamping apparatus respect already, also have the effect of workpiece oneself element. Undoubted, machine the seeks to ensure workpiece machines quality just about base of condition. Additional, to clamping apparatus " search " the deviation that measures in the process, and because be worn away by temperature change and cutting tool,wait for action of gradual change element, the meeting that the stability place that machines condition produces affects the change of finished products quality, returning when necessary need to take step of a few compensation. In machine main effect also was produced during measuring a system to be in. Of workpiece detect automatically after a working procedure ends, perhaps be in after all working procedure already were finished, undertake be metricaled automatically to workpiece again, be in what pair of finished products carry out on the machine tool to examine directly namely, be machine another kind of function that immanent machine measures. Right now, be equivalent to measuring a coordinate machine moved on the machine tool, apparent, this can reduce the auxiliary time that off line measures greatly, reduce quality-related cost. In fact, nowadays is in this kind machine measure a function also truly very powerful already, detect quickly besides what can have all sorts of geometry elements outside, the software that uses special development still can finish off line process designing, through be in computer imitate, still can avoid to be in machine the phenomenon such as the happens possibly interference in measuring, collision. 2, application is in before example machining center is old domestic mechanical manufacturing industry already applied somewhat, but be in machine the equipment of control of a kind of process that testing system just still appears nearly 10 years and means. Because can have promoted programmed control to restrict ability significantly, rise production quality, work efficiency and reduce accident, the application of production industry of automobile industry, etc of aviation of mould, spaceflight to its rises extensively gradually, and in automobile industry, the application of the factory such as car engine, gear-box with each passing day grow in quantity. A few more the following the give typical examples with the actual production that comes from automobile industry provided sufficient specification. 2.

1, temperature compensation and cutting tool wear away before compensating 10 years, the factory is checking and accept some engine one flexible the crock builds automatic product line, be opposite among them parameter of a few crucial and linear dimension has 2 machining center when equipment ability assess, discover machine capability index can satisfy a requirement. But when should carrying out process ability to evaluate, namely when to continueing class or 2 longer sampling observation data undertake statistic is analysed, appear dispersive sex is bigger, the process capability index, circumstance that is worth on the low side, namely the requirement that short of of working procedure quality sets. The course is more comprehensive to the cause that causes possibly analyse, environmental temperature change causes affirm, apparent, if do not accept compensation,measure eliminates the error that causes from this hard. Finally, be in through was being added to the machine tool machine detect function, solved a problem thoroughly eventually. The method is: Deserve to touch hairdo to measure a head in knife library, basis beforehand the frequency of set second (be like 1 times / 10) , as taking out the land like cutting tool, the some that is hit on the clamping apparatus that installs workpiece secures the position. Because judge the change that gives this one seat and controlled key correctly,is linear between dimension relevant, because this is OK,the change that is worth according to be being measured adjusts feed amount, carried out compensation effectively thereby. No less, undertake temperature compensation or cutting tool wear away compensation also can use another kind of method. Not long ago, southern one car engine the dimension precision after the factory machines crock of Gai Shangping face to ensure, adopted the measures a head to be hit after milling ends workpiece in aircraft capacity appearance apparently, undertake metrical by every 10 1 interval. If discover bigger error, machine parameter according to the compensation means self-correcting of set namely. Generally speaking, suffer temperature change or the wave motion that cutting tool tatty is affected and bring to present regularity, can decide corresponding compensation way accordingly. 2.

2, the set of parameter of machine tool treatment pursues 3 medium aluminium pledge cylinder body needs Lang to embed cylinder bushing, cylinder bushing is bought-in component, its install plane (arrowhead of the green in seeing a picture indicates) under the plane on cylinder body (be caused by of arrowhead of the red in seeing a picture) , a working procedure of this machining center is to machine this cylinder bushing to install plane namely. The axial distance H that installs plane to ensure the plane on cylinder body comes can be controlled inside limits of formulary public errand, installed inside the machine tool in machine testing system. This working procedure needs pilot H to be worth is by the bottom of cylinder body plane arrives go up the height of planar height and cylinder bushing decides, namely: H=- - L secures the bearing face at machine tool clamping apparatus as a result of plane of cylinder body bottom, latter is the datum plane of treatment, and L is calm value, because this gets to ensure consistent H is worth, must pass in machine detect after the value that gets every work, will decide corresponding cutting measures M again: M=- - (H+L) particular way is a graph 3 touch hairdo mediumly to measure head order to be in of cylinder body on plane measures 4 to nod, take average by gotten data, next by before already the cutting quantity that set value will come to request a photograph correspondence, machine the basis when cylinder bushing installed surface as next line working procedure. 2.

3, clamping apparatus searchs to pursueing 4 shown machining center have huge, call " exchange implement " revolving stage, in its diametical direction installed 2 " tray " , it is 2 circumgyrate workbench that are used at holding clip work actually, can carry Xiang An on the back to install 2 crocks to build case. 2 workbench are located the position always is corresponding machine tool before, hind " expect up and down " and " treatment " labour, be in when a group of workpiece namely when working station is made machine by order, jockey is versed in in fluctuation makings a discharge after be engaged in working procedure ending and go up again makings. "Exchange implement " and " tray " circumgyrate precision is very tall, but former when exchanging two workbench position, must first by lift litre of orgnaization to raise whole revolving stage, turn next 180 ° , fall to be comprised by 4 cone, taper hole again, rely on the tabulator that cone matchs. Because working environment is harsh, the aluminous bit that hard to avoid can have cooling fluid to be taken, sundry wait for conglutinate to be on fixed position face, can cause the minim deflection of revolving stage from this, deliver workbench (" tray " ) the clamping apparatus that goes up with its. But the principle of tabulator and structure decided, also ensuring minim deflection is only likely is translation, and cannot be askew. From the graph 4 visible, the crock lid case that is machined is erect outfit clip, if incorrect this one element that causes an error undertakes monitoring, will go against the quality that assures workpiece, for this, arranged in machine detected link, search with what provide at clip, say exactly, it is to pass " search " undertake compensating. Specific executive means is on workbench the upside of clamping apparatus is set one fiducial piece, when the working station of workbench park machine tool, before to workpiece executive cutting is machined, head first v measures a head, hit in fiducial piece on facet (see the graph is shown 4 times) , pass with beforehand the condition that set value photograph judges clamping apparatus quite, should appear when the deviation that exceeds limit, inform an operation personnel or machine repair personnel to undertake handling namely. The graph shows the basis 4 times by the actual condition of treatment workpiece, this allow poor limits is ± surely 0.

2mm, should be in namely machine metrical outcome is less than ± 0.

When 2mm, think to be able to solve the machining error that clamping apparatus deflection causes through compensation. It is in the treatment process later, through the compensation value that correspondence introduces in parameter is being estimated in cutting, in order to remove the bring effect of clamping apparatus deflection, ensure thereby the production quality of workpiece. 2.

4, workpiece searchs to be being machined workpiece is the large aluminous cast on engine of a kind of novel car -- chain wheel case, in the numerous working procedure of this machine tool, right among them the treatment of 4 aperture is very important. Graph 5 in, from left to right showed these hole, among them the 4th, also be most on the right side of one is being gone wait for measure (be equivalent to " treatment " ) the position. To ensure the treatment quality of aperture, must make on craft the center of the centre of turning circle of cutting tool and aperture of work semifinished product keeps consistent. But see from inside the graph, 4 aperture submit radiation, dispersed form, gao Youxiang differs bore diameter and center very big. Below this kind of circumstance, if still implement invariable machine program to each workpiece, so even if the nuance in holding clip, or a few difference that are cast oneself, will affect the production quality of aperture. For this, must have a plan to workpiece first 5 in machine detect use at workpiece to search " search " , use a machine tool namely in machine before testing system is being machined first one by one is right Kong Jin measures every semifinished product all right. The method is the coordinate position that came to accurately affirmatory aperture center at 4 o'clock through be being hit in all in circumferential fluctuation, left and right sides, accordingly, again specific aim ground carries out the treatment of each aperture, apparent, through " workpiece searchs " later, the production quality of each aperture had assure adequately. In addition, searching while, return the semifinished product surplus that can obtain casting aperture, if use variable process designing further, allocate automatically what still can achieve semifinished product surplus, power of the cutting in can making sure aperture machines a process already so won't be too great, lest injure machine tool and cutting tool, can raise the durability of cutting tool again, in order to make work efficiency is achieved highest. 3, in machine metrical application promoted working procedure quality to use a setting inside machining center in aircraft capacity appearance makes be opposite inside machine knife, before passing treatment in machine measure the automatic set that completes relevant treatment parameter, or carry out to clamping apparatus, workpiece " search " , have corresponding correction, compensation accordingly, and pass after treatment in machine measure undertake tatty of temperature, cutting tool is compensated. Every this a variety of, not only the treatment quality that assured a spare parts, and the quality level that raises manufacturing process effectively to move. Graph 6 it is an example 4 (2.

4) process ability analyses a result, chosen evaluation it is a graph 5 in measure a head to undertaking searching that aperture: , also be 4 are looked for a the demand in aperture is top. The treatment quality for objective of test and verify and the quality standard that produce a process to move, during be being produced normally according to a month the data of normative sampling, undertook statistic is analysed. Graph 6 in, a is graph of only cost process, also say " medicinal powder the dot pursues " , during mirrorring this, be machined metabolic trend, b is histogram. Accordingly, calculable a target cost that process riding quality produces during evaluating this -- CP of process capability index, CPK, gotten eventuate: CP=3.

24, CPK=2.

95, the working procedure quality that demonstrated this machining center apparently already reached quite high level. Graph 7 it is an example 3 (2.

3) process ability analyses a result. From the graph 4 - B can see, through be in machine those who measure pair of clamping apparatus " search " and after having corresponding compensation, the work measure parameter that improved precision directly is with head axes is the same as to high value, because the size of this value depends on completely,cutting tool is opposite the milling quantity of workpiece vertical plane. Be similar to afore-mentioned is opposite the statistic of 4 analyses example, produce quality and the working procedure quality that produce a course actually of workpiece for test and verify, the data that also be obtained with means of normative sampling observation to a month did an analysis, assess object is workpiece locates the face arrives graph 4 - be machined in B the distance of the face: 20.

4 ± 0.

2. From acquisition only cost the process pursues (graph 7 - A) with histogram (graph 7 - B) , and during mirrorring this via what computation gets from this the index of level of process riding quality -- the value of process capability index: CP=3.

33, CPK=3.

01, also showed working procedure quality is quite high. In this case, use in machine measure a process to controlled a method to promote the treatment that is located in a machine tool to machine the spot quality directly, reflected modern industry very well " product quality is to make come out " this one concept. CNC Milling CNC Machining