CAPP applies mediumly in CNC Machining

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A procedure design is plant technology branch regular the technique works, it is the first step that production plans to work, also be the intermediate segment that join products plan and product produce. Traditional procedure design is by the technology that has rich practice experience the engineer is held the position of all the time. As the development of computer technology, the computer assists process to design (CAPP) replaces craft engineer's onerous repetition to work in great quantities. The development of computer technology reachs his to make the wide application in the domain in machinery, for process the design provided ideal tool. Connect with CAD on CAPP, fall to be linked together with CAM, formed thereby a kind of new-style contemporary design and production technology. Can be CAPP system divided into: of 3 kinds of forms by its job principle? Be good at ⒋ of  of copy of be good at ⑴ enters stew have a nightmare moisture in the soil asks in  of sour of be good at U fall graceful  of small cup of ひ of  of languid of pry of act  ∈ casts craft of noise? standard, typical craft, make technology. Among them, the computer that achieves type CAPP assists technology the design is most complex. Achieve type CAPP to make make type again. It and derive type CAPP are different, do not build instead base with be being mixed to the retrieval of typical craft. It is the spare parts information that perhaps obtains what the basis inputs from CAD system directly, the technical data in relying on a system and decision-making means make the system of the process of the spare parts automatically. According to specific spare parts, each working procedure that the system can machine place to need from movable raw spare parts and treatment are ordinal, automatic extraction creates knowledge, finish a machine tool automatically to measure of clip of choice, labour chooses and machine process optimization; to adopt applied technology decision-making logic, can the decision-making process of personnel of imitate technology design. Achieve type CAPP craft the design is achievable the decision-making process of complex mutiple level, much task. It involves the job such as choice, computation, program, plot and file editor. Achieve type CAPP system to not be a foundation with standard procedure, however from 0 begin to generate a new procedure directly according to spare parts information by software system. Selected a part when the system the treatment method of each surfaces and after arranging treatment order, be about to undertake detailed working procedure is designed. More important to the spare parts that machines on numerical control machine tool. The process general interest that achieves the CNC Machining that has a part on numerical control machine tool into type CAPP has the following flow: 1.

The choice of choice treatment method of method of cutting surface treatment is the process that the process capability information spare parts information and factory has matching actually. The part is formed by a lot of surfaces, often include the cutting face that has a variety of typical cases, surface of the circle outside be like, aperture, chamfer, planar, figuration is waited a moment. To surface of cutting of model of avery kind of, the precision that all can list all sorts of treatment methods can be achieved reachs exterior surface roughness. Accordingly, after the message that identify or understood surface of spare parts cutting, but according to particular case, choose the most appropriate treatment method. The choice that machines a method needs a series of logic is decision-making. Typical treatment method is to show in interior of enterprise of analysis, summary the contains general and direct import alternative that offers after experience of all sorts of production technique, production and the standard that concern with treatment machines methodological criterion. It develops as technology of updating equipment, production and change, have bigger flexibility so. Some criterion are ambiguous, this is the blame consistency that working procedure designs. These characteristics are being assisted with the computer should give when process is decision-making proper consideration. 2.

Treatment is sequential arrangement treatment is orderly arrange what point to working procedure early or late, closely related it and treatment quality, productivity and economy. Arranging what treatment should consider above all orderly is technology datum plane, locate especially fiducial. Locate the requirement that learns by mechanical workmanship answers when fiducial choice, by thick, essence fiducial choice principle undertakes. Working procedure of machining order, heat treatment, auxiliary working procedure and the treatment that have on machining center machine tool, the requirement that all should learn medium treatment to be arranged orderly by mechanical workmanship undertakes. Anyhow, treatment is sequential arrangement is a more complex issue, the issue that wants a consideration is very much, actual condition is agile also and changeful. Current, the decision-making and logistic research of this respect is still immature, very difficult summary gives general decision-making pattern, can press specific production environment and boy or girl friend of specific spare parts only, design corresponding decision-making pattern. 3.

The choice machine tool of machine tool and tooling chooses the treatment quality to working procedure, productivity and economy to have very big effect. Power of force of it and treatment method, cutting, cutting and machine tool utilization rate are relative. When the machine tool chooses, but the treatment method information that place of the information of machine tool norms in the machine tool database that will build beforehand inside CAPP system and spare parts information, spare parts chooses is compared, make next decision-making. Power of force of cutting of dosage plan cipher out, cutting undertakes the cutting that can press spare parts and the requirement that its machine a method to make primary election; be gotten according to choosing again next first commonly some systems return school nucleus; can undertake be adjustmented appropriately according to machine tool utilization rate. Tooling (cutting tool, clamping apparatus) choice and machine tool option are similar, the treatment method information that needs to choose according to place of spare parts information, spare parts likewise namely goes and build the information photograph in tool database to compare beforehand, make next decision-making. When doing not have off-the-peg general tool to be able to be used, CAPP system should raise the requirement that special tool designs. 4.

Does the affirmatory mental allowance of mental allowance have: of 3 kinds of methods generally surely really? Beat treat Mian to attack Mian of Mei Zhi of S of ā of Ju of  of road of ê of Gan of Chinese catalpa of Zhui ā ⒉ attacks Zhuo of humorous of gizzard of box of collate of be angry of び of model  commonplace is worth Zhui ㄈ mire persimmon Xia Bachen analyse  Qian  of danger of persimmon of Feng of  of apology of ㄊ of Gan of 2 Chinese catalpa. But because form is general, cannot consider particular case. Experience law is technologist basis experience will decide mental allowance. 5.

Use of working procedure dimension and public errand commonly certainly " by hind forth " method, press part drawing demand first, define the dimension of final process and common difference, the mental allowance that presses make choice of again pushs the measure of the working procedure before cipher out. Tolerancepublic errand machines methodological precision to give out by this working procedure. When fiducial changeover existing in be being designed when working procedure, undertake conversion of working procedure dimension with respect to need, seek solution with technology measure catenary namely. Right now, can seek solution with the computer through building mathematical model. The method that uses mathematical model to seek solution and move are as follows: (1) builds dimension to contact matrix. Dimension connection matrix is model of a kind of maths, dimension of the semifinished product in mirrorring a spare parts to machine a process, working procedure dimension, final measure reachs his mutual the connection between. It comes by the chart of technology measure catenary of the spare parts, it is to use computer calculative source. (2) builds dimension catenary matrix. Benefit can contact matrix to search a catenary of each working procedure dimension from dimension with the computer, build dimension catenary matrix thereby. (Deviation of dimension of 3) computation working procedure. With the computation of extreme value law formula is a foundation, press the linear equation that designs beforehand, benefit has consideration with the computer, decide dimension of each working procedure and its deviation. 6.

The affirmatory cutting dosage of cutting dosage is to point to cutting speed, feed and cutting deepness. Of cutting dosage decision-making the methodological know exactly how things stand that often uses learns a model law and check manual to choose a law to wait. Mathematical model law is to carry much experimentation research, the all sorts of cutting tool and treatment method maths model after obtaining parameter builds corresponding model warehouse, at the same time mathematical model in with material of workpiece material, cutting tool, cutting tool the concerned parameter such as durability, cooling fluid is written into data file to stock a library in, so that be called when mathematical model computation. Checking manual to choose a magic art consider to accumulate according to long-term experiment, course analysis is arranged, to the life of all sorts of cutting tool cost plan decides deepness of corresponding cutting rate, cutting and feed, and accordingly consummate cutting dosage manual. Be in specific when undertaking cutting dosage chooses, the limitative computation feed that presses the deepness of cutting of requirement primary election of cutting surface quality and feed; to press cutting power again first, can choose great value; to give power of cutting speed, cutting according to computation of cutting tool life again next as far as possible. If calculate gotten cutting dosage to cannot satisfy requirement of cutting surface quality, need to amend feed again. Relapse so, till satisfy the treatment of the spare parts,surface roughness of precision, surface is mixed till cutting tool life. 7.

Of process chart generate with scale process chart the graph that is technology design expresses kind. Process chart of the development in CAPP system builds the efficiency that module designs to improving technology and mass, the standardization that realizes technology design has very important sense. Current, the process chart scale of CAPP system still is difficult problem of a when CAPP system is developed and develop decisive technology, because,this is it and normally computer plot differs somewhat. Latter rises to replace job of artificial executive plot merely. In CAPP system, of process chart the process that building a course is a kind of trends, cannot secure its graph information completely. When the appearance of workpiece, dimension is changed, corresponding plot information parameter also wants a change, in order to get used to the metabolic requirement of working procedure. This shows, of process chart building a course is a kind of union actually information of part drawing form and treatment craft information, assist the process that makes news of process chart form by the computer. Process chart is generated and scale looks from the function, can divide for information changeover, graph is generated, dimension is tagged reach blame dimension to tag wait for a few stature module, if pursue,1 is shown. (1) process chart makes plan from process chart generate mechanism to look, can adopt the different plan such as set code law, appearance parameter law and mathematical model law. Build into set code law go up into group technology base in the spare parts, build the warehouse of geometrical graph element that presses spare parts a group of things with common features to deposit beforehand, serve as with the code of the spare parts retrieve, spell the basis that close. To satisfy all sorts of structural part requirements, structure of its graph library is huge, the difficulty that build a warehouse is greater also. Appearance parameter law is a basis parameter plot principle, essential factor of part drawing form depart becomes graph element unit, in the light of every kinds graph element unit writes subprogram of a plot, these subprograms formed CAPP process chart to assist the plot in making software child module. When working procedure is designed, give out the working instruction of every working procedure. These information are plot child the input parameter of module, the plot subprogram of unit of every graph element sets an appearance label. Input parameter can enter corresponding plot subprogram conveniently, scale gives corresponding figure. The foundation of mathematical model law is the mathematical model that builds of all kinds part, also be to apply into group technique to undertake classified to the spare parts, build a complex part for of all kinds spare parts next. After undertaking analytic consider and inducing generalizing to composite spare parts, abstraction goes out to already machined the surface to depict the model of spare parts maths that give priority to. When CAPP system works, produced every working procedure to have the news of the change to machining the surface. At this moment, process chart generates a system to answer the mathematical model that the basis already built, to machining exterior description information undertakes reconditioning, make the news of dimensional vector data of element of every geometry in process chart automatically. Next, go further make news of data of coordinate of geometrical element space automatically, get the process chart of need. (Data of graph of 2) process chart generates data of process chart graph the key that generating is process chart scale, data of process chart graph originates craft conclusion. Law of a kind of unripe set prescription is direct take out data from inside working procedure content. The data that the basis takes out can make data of process chart chart, working procedure of requirement of means of this kind of processing and description of labor situation content want very detailed. Additionally one kind is design by process chart decision-making generate data of process chart graph. Working procedure content is generated by working procedure inference, working procedure content is implicit in regulation of inference of design of working procedure content. So, from working procedure content the derive in designing inferential regulation gives process chart to design inferential regulation, design inferential regulation to generate data of process chart graph by process chart again. Data of process chart graph is generated child the diagnostic information file that module reads in a spare parts above all and technological process. According to technological process, the system undertakes searching to catenary of spare parts feature, locate the feature that answers relatively with treatment content area, offer this feature model dimension information, after choosing via mental allowance inference, can obtain the graphical information that place of feature of the scale on process chart face wants. (After 3) decides process chart outputs data of graph of plan process chart to generate, can process chart have the following kinds of methods to output: ? Americium of team of Luo  enzymatic M is grown brag attack? of Nao of ば of Yu of  of Qian  small box next printout. This way is simple, but output graph quality is low. ② uses advanced language to use the plot instruction process designing of graph plotter directly, on graph plotter the picture gives process chart. This law rate is rapid, graphical quality is high, but suffer graph plotter model to restrict. ③ uses AutoCAD to output process chart. Its method is an AutoCAD2 of work out of exorbitant level language second development program: A.

The figure that makes AutoCAD directly by advanced language exchanges file [.

Dxf] . This file structure is complex, process designing difficulty, take up a large number of outside put a space, but this kind of method makes graphical career fast. B.

Generate the command file [of AutoCAD directly by advanced language.

Scr] . This file can copy each function of AutoCAD, the structure understands easily simply, facilitating process designing, but the executive time of the file is long. C.

The ADS that uses AutoCAD or program of plot of ARX language work out, the data in the data document that produces by advanced language program is called when plot. Use this method, the system has certain flexibility, the data in the data file of the generation when be being designed by CAD can be called directly when plot, simplify design program, graphical subsystem easily augment and safeguard. CNC Milling CNC Machining