Optimize the hob before designing gear shave

8normal Align=center> experiments 3 Normal Align=center>70normal Align=center>546normal Align=center>1 ' 15 " Normal Align=center>l.

The allocation that 2 hob chamfer counts is the task that needs thorough research likewise, be in identical outside below round condition, the addition that groove counts is equivalent to the cutting amount that in the hob in the process of same rotate speed every discharge tine reducing, of such hob wear away degree can be reduced greatly, improve the service life of hob then. The cutting amount that if make every are discharged,ages conversely is same, can improve cutting efficiency greatly, reduce gear hobbing time. Can make the test above likewise, such OK the more reasonable groove number that selects hob. Graph 3 show 3 times like the graph, use length effectively of hob to be concerned with the size of emery wheel diameter in machining a process, with blueprint requirement hob hind horn (the quantity that shovel a back) about, in the horn after emery wheel size is mixed same situation falls, the groovy number of hob is more, criterion the space that emery wheel walks is less, use length effectively smaller, blade wears a number less. Computation but the basis pursues 3, in emery wheel size foregone circumstance falls, emery wheel intersects when point of a knife of tine issueing a platoon, affirmatory emery wheel and shovel back estimate the place of circular arc node, can calculate a graphic representation to use the maximum of length effectively so. (For example, the diameter is 85mm hob, form of standard of the chamfer that hold bit 11 chamfer, the quantity that shovel a back 4.

25, 60mm of emery wheel diameter, use length effectively to be able to be amounted to 8.

5mm left and right sides. ) pass mass data accumulate the chamfer that can find special ideal to count program, the effect is very apparent also. (2) pours horny treatment to aging teeth of a cogwheel supports, the architects of hob are very much nowadays had been calculated very accurately, it is the research that position of horn of the many clench the teeth in hob and process of gear clench the teeth affects. The optimizes a design thought here is to will pour horny angle to increase, body pursues namely on hob now 1 in the angle that bottom tilts, pursue namely 4 in the angle that Hd dot carries on the head to tine. And the change of this angle to dimension H. volume has immediate effect, the requirement on a lot of blueprint and craft is 45 ° , and because this pours horn to be involute and tine have a common boundary, be not simple two perpendicular edges pour wine cup, if the angle of this one part of hob is designed,be 45. Be in the length that creates character and height intuitionistic on looking is unequal, such not beautiful. But more important is this angle is increased, apparently will OK make if the graph is shown 4 times,the with gear hobbing hind involute length span before gear hobbing is reduced, because gear hobbing tooth form and shave tine tooth form age the top falls to horny angle is increased and make change of Hd spot position is reduced. Can raise shave tine to machine the stability of the process so. Tine prevents after here must notice to increase angle become pointed. The design of salient of graph 4(3) hob is the difficulty that hob designs, and the performance characteristics that its calculative accuracy affects hob directly. Pursue namely 1 in HC the design of this one part. Reflect a plan 4 it is the shaping under Rg1 dot, this one part designs; Zhui truly the gear wheel that the gender can control treatment accurately is effective involute length, and the connection with having very fundamental with razor design (below) can be experienced in razor design. Length of involute of gear hobbing pilot has a paragraph of space that can choose, the adjustment that this ages to shave equilibrium clench the teeth is nodded is very advantageous, and drop of shave tine clench the teeth is initial the picture that gives by hob design namely 4 in Rg2 this. Perhaps be told alone to hob design should make sure length considers enough involute reasonable only, but can not make the product achieves optimal to machine precision certainly, and this also assure to boil just about, shave hands over the key that is ideal. Graph 4 in the computation of Rg1 and Rg2 uses iteration calculation, its are accurate degree is very tall, involute of the gear after design thought should consider shave above all and tine root transfer 4) of graph of curvilinear node Rg2(should be in tooth form is effective and bit more initiative the following, can build equation through growing a cycloidal equidistant line and involute next (can consult) of gear design manual. This equation from build seeking solution is a very complex process, iteration operation can be calculated the convergent value that gives Rg2. But theoretic it is two node, because the node below uses iteration operation,be only cannot convergence gets determining a value, this and the maximum that the external diameter when razor is designed allows are concerned, very important to preventing interference (referenced graph 5) . The computer assists computation to be able to undertake assigning with circular method now, after listing all results, you can find this. Checking computations razor designs clench the teeth to nod a circumstance to be able to get optimal seat, such hob is very Utopian. Choice salient height pursues 1 in H is worth (increase on the foundation that is shave tine allowance commonly 0.

025mm) . The intensity that can make sure value of the H below as hands-off as razor circumstance chooses pairs of smaller gear wheel is more advantageous. This has very big concern according to actual condition, and H is worth decrease young general to be repaired to razor grind size control strict all the more. After graph 5(4) this requirement is achieved, the 1) of graph of Af(of tooth form horn that is not shaping cutting blade certainly, we can be calculated this point of view is the oldest allow a value, take this angle to be in formulary limits next can. If exceed this angle, so participate in shaping to design the salient that to going up interview goes to here optimize without any meanings. (5) changes a design be being used is a kind of newer technology in hob, change the occurrence of a design, make hob appeared in use respect a lot of advantages, and home also has very much person research changes design and already expounded its numerous virtue, the specification wants to change here a two gear of COS An of × of C0s An=Mn of × of design basis Mn are OK the principle of clench the teeth, parameter of will original gear is adjusted for additional the gear parameter with a same basic circle undertakes designing hob. Most design thought is to make hob modulus and pressure angle are reduced. Graph 6 boil to optimize design hind, shave treatment graphic representation pursues 6 after be being designed to optimize, boil, shave machines graphic representation, blue line is gear hobbing tooth form, red line has delimited for shave tine tooth form and razor point of a knife orbit, black line ages for mating gear a contrail of clench the teeth. Can see thirdly person the rationality of clench the teeth. (6) increases hob tine to carry circular arc on the head, increase treatment to give circular arc of gear root ministry namely, increase gear strength effectively, this is very necessary in lorry gear, this respect if two gear have enough unoccupied place, criterion make it odd circular arc is unchallenged, with above of says contradiction lie to want loss involute length to choose limits at increasing circular arc, moving integrated grain so is to be weighed particularly want. Razor design should realize hob to optimize a design to must have enough research likewise to razor design, only ability of sufficient to razor design understanding masters hob effectively how to achieve optimal result. Here does brief analysis to razor, the necessity that can more effective understanding above place becomes. Razor of the requirement when designing razor alone is finished from gear clench the teeth initial drop arrives stop the shave that nods this paragraph of involute to cut a course, but it is better to want to obtain tooth form is best will be in when razor and gear clench the teeth gear wheel holds from beginning to end in postponing a process item of check the number of clench the teeth of or so tooth flank is same, tooth form of this kind of circumstance " S " form or in sunken occurrence possibility lowest, referenced graph 7. Graph 7 below the consideration that we see the razor below ～ and β of gear jackknife coefficient, its adjustment can change the position that clench the teeth nods. Reference can undertake in rolling razor to match a design. Among them Da1: By round diameter of shave gear top; Da0: Razor carries round diameter on the head; Db1: By diameter of shave gear basic circle; Db0: Diameter of razor basic circle; β B1: By helix angle of shave gear basic circle; β B0: Helix angle of razor basic circle; Z1: Be aged count by shave gear; L ' : New razor and after be being designed to finish to a hob by length of the path of contact when shave gear clench the teeth, its involute length is already affirmatory, razor architect can use line of razor public law only adjust did not change clench the teeth to nod. Can give out so line of one reasonable razor public law, so one but hob design is finished, razor designs adjustment space to will become very little. The last word is current our country is conforming at level of as advanced as the world technology period, to the precision of car gear the demand also rises ceaselessly, also want to the design of cutting tool respect more attentive, be being improved continuously is to be in what a preeminent company and each among them person must want do. To home treatment level still has very big rise space, also existing among them a lot of inadequacy, so the design of a few transverse elements to cutting tool optimizes other to also have certain shadow Ⅱ to, be like machine tool precision, tool precision, steel makings, all sorts of cutting oil machine metropolis influence quality, actual condition of production should be clear about surely when so cutting tool is designed, undertake be optimizinged stage by stage again next. CNC Milling