Hob gear hobbing machines the computer of the process to include simulation of subsidiary channels in the human body through which vital energy

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Gear hobbing is one of commonly used methods of gear cutting. The validity that hob designs is to assure to be machined gear wheel is right dentiform is important premise. To the hob before shave (have salient and long predestined relationship) tooth form design is more complex, appear easily the design is wrong, cause cutting tool repair to discard as useless even, affect normal gear to produce. If use the computer to undertake gear cutting imitate to designing the hob after, the validity that can design to hob tooth form undertakes test and verify. 1. Hob imitate machines principle hob to machine the principle of gear to become a law to exhibit. Actually, the axis in gear is sectional go up, hob cuts the process of gear to be able to regard rack approximately to cut the course of gear, be by the tooth form of treatment gear namely rack (form of hob tooth cut) the curve including sth resembling a net of line of two side tooth form. And the relation of clench the teeth of rack and gear can use a figure 1 will express, can building the following coordinate by the graph is: The coordinate that P-xyz connects to originally with frame photograph is, the coordinate that O2-x2y2z2 connects to originally with gear photograph is, the coordinate that O1-x1y1z1 connects to originally with hob photograph is (P dot is working pitch point, o2 dot is gear center, r2 is) of radius of pitch circle of gear clench the teeth. Graph the coordinate department of 1 gear and rack clench the teeth moves coordinate to fasten O1-x1y1z1 in hob in, if shift is apart from L, fasten in gear coordinate turned relatively in O2-x2y2z2 2 horn of φ , by the clench the teeth of both pure scroll the relation has φ 2=L/r2, accordingly, when taking different L to be worth, hob tooth form can be in gear coordinate department hold different position, form all the time line a group of things with common features, and in gear coordinate department this all the time the line including sth resembling a net of line a group of things with common features is machined namely the tooth profile of gear. As a result of linear a group of things with common features the process that fashioning a process is hob gear hobbing, because this is usable and linear a group of things with common features form a process to come treatment of imitate gear hobbing, with linear a group of things with common features the line that include sth resembling a net will examine the tooth form that processes gear. By coordinate commutation concerns knowable, coordinate department O1-x1y1z1 and the commutation relation that coordinate is O2-x2y2z2 are (1) 　 by above relation knowable, if roll knife tooth form each a little bit coordinate is foregone, can calculate the coordinate value that gives tooth form to fall in gear coordinate department. It is with the hob before shave below exemple, introduce course of rolling cut imitate. 2. Computer simulation machines a graph sketch map of tooth form of the 2 hob before be shave. If plan institute shows left and basic tooth form to be AB, the tooth form that build a predestined relationship is BC, heavy angrily form is AD and DE. Basic tooth form is ′ of A ′ B on the right side of, the tooth form that build a predestined relationship is ′ of B ′ C, heavy angrily form is ′ of A ′ D and ′ of D ′ E. Because each paragraphs are linear, ask the coordinate that goes out each a little bit can decide equation of each paragraphs of dentiform only so. By given parameter of hob tooth form must nod coordinate to be 　 XA=hAtg α each, α of XB=(h-LZcos of YA=hA 　 　 ) Tg α , XC=htg α of 　 of YB=h-LZcos α 　 - α of Htg α X+LZcos () of α of Tg α X-tg, α of XD=hAtg of YC=h-H 　 　 + (HD-hA)tg α T, α of XE=hAtg of YD=hD 　 　 + (α of HD-hA)tg α T+(h-hD)tg, α of =S-hAtg of ′ of XA of YE=h 　 　 , α of =S+(LYcos of ′ of XB of 　 of 　 of ′ of YA ′ =hA - H)tg α , YB ′ =h-LYcos α pursues =S-htg of ′ of XC of 2 hob tooth form α + α of Htg α X+LYcos () of α of Tg α X-tg, α of =hAtg of ′ of XD of 　 of 　 of YC ′ =-h-H - (HD-hA)tg α T, α of =hAtg of ′ of XE of 　 of 　 of YD ′ =hD - (α of HD-hA)tg α T-(h-hD)tg, 　 of YE ′ =h takes the place of coordinate of each bits into equation (in 1) , with respect to attainable hob tooth form each end points moves coordinate to fasten medium coordinate in gear, each bits of join, must fasten the tooth form of hob blade ministry below in gear coordinate namely. If alternate coordinate formulary (the 2 situations with be pressed particular grow the φ in 1) to take a cost circularly inside certain limits, attainable in gear coordinate the department leaves curve of tooth form of hob blade ministry a group of things with common features, to this tooth form curvilinear a group of things with common features undertakes including sth resembling a net, can reach hob place processes the gear tooth form that give. Benefit undertakes with the computer above alternates very easily. Use the BASIC language with computational stronger function to undertake the coordinate commutation of end points of each tooth form is calculated above all, form coordinate of each bits data filestore to rise, next, below the support of AutoCAD software, adopt the AutoLisp plot program of the work out, on screen draw gives tooth form curve a group of things with common features, see a picture 3. Because need to get a complete dentiform includes sth resembling a net only,pursue can, so the extraction of 2 is worth φ interval should be cut from left blade begin to cut an end to right side edge. The element that another decides to tooth form includes precision of subsidiary channels in the human body through which vital energy is φ the 2 steps that take a cost circularly inside interval are long. The condition is chief lesser when, can obtain the very tall precision that include sth resembling a net, because this is examining,the tooth form that rolls tooth form can use lesser pace to grow when horn and tine compasses dimension, but enumerated data is right now more, the scale rate of the graph that include sth resembling a net is slower, the machine takes up memory is older; The condition is chief bigger when, although precision of bag sth resembling a net is poorer, but plot rate is rapid, and the analysis of tooth flank surface roughness that can make the gear after rolling cut. Graph 3 hob tooth form curvilinear a group of things with common features and bag sth resembling a net pursue 3. Gear tooth form examines reach machining error to analyse (1) in be being examined in actual gear tooth form by treatment gear dentiform, because seek a hob blade form very hard the equation of the line that include sth resembling a net of curvilinear a group of things with common features, so we also adopt gear tooth form program scale to be on screen, through gear tooth form with the joint degree of curvilinear a group of things with common features will examine tooth form. If give out 2 conditions of φ are chief very small, the tooth form of gear and simulative roll tooth form joint of curvilinear a group of things with common features is gotten very good also. (2) below the circumstance that is in to make sure gear tooth form is proper by analysis of machining error of treatment gear tooth flank, if press the machine tool rotate speed that gives out on craft to decide the pace of 2 grows φ , the knife number that place of individual tine hob cuts a gear is cut to be opposite when pressing effective treatment strictly namely φ 2 take a cost (right now the pace of 2 grows φ general bigger) , what can pass AutoCAD on screen is local can inspect a function to undertake surface roughness of gear tooth flank is analysed, if pursue,4 are shown. The volume that gives tooth flank arris to spend can be measured on screen, will examine from this the validity of craft parameter. Graph microgram of tooth flank of 4 treatment gear (3) dentiform of design of blame involute hob examines the design to hob of gear of blame involute dentiform also can use this imitate method to undertake test and verify, be about to roll tooth form to undertake on tooth depth equational, recover each equational points, recycle this method can. Divide into equal parts of hob tooth form is more, more accurate. Conversely, also can be not involute dentiform circumstance to come down to design blame involute hob in foregone gear, can regard a kind of hob as the graphical method of the design. CNC Milling CNC Machining