1、STD-AGMA S5FTMLZ-ENGL 1775 = 0687575 OLi781 BTO 9 95FTM12 Flank Modifications in Gears Using a Universal Bevel Motion Concept by: Hermann Stadtfeld, The Gleason Works 1 I TECHNICAL PAPER COPYRIGHT American Gear Manufacturers Association, Inc.Licensed by Information Handling ServicesFlank Modificatio
2、ns in Bevel Gears Using a Universal Motion Concept Hermann Stadtfeld, The Gleason Works me statemenrs and opinions contained herein are those of the author and should not be construed as an official action or opinion of the American Gear Manufacturers A.wdation.1 Abstract The use of fire form bevel
3、gear generatos was iimited by the processes currently available to cut bevel and hypoid gears with face mill cuter heads. Since a he form culling or grinding mache has three rotational and three linear freedoms it is posible to perform all possible reiative movements between the cutter and the work
4、during the generation process. The trial to use the six axes of theh form machinedirectly in orderto produce new andmoreadvanced flanlr forms had never areal break hrough since those axes had no reiation to the gear theory. The universal motion concept is applied to axes of the basic gear generation
5、 model only. It aiiows each of them to change the setting during the generation process according a higher order function. is approach enables a free form gear machine to produce an entire variety of modincauons to the fhk surfaces. Coppight O 1995 Ameican Gern Manufacturers Association 1500 King St
6、reet, Suite 201 Aiexandria, Vi 22314 * October, 1995 ISBN. 1-55589-661-8 COPYRIGHT American Gear Manufacturers Association, Inc.Licensed by Information Handling ServicesSTD.AGNA 95FTNLZ-ENGL 1775 m Ob87575 0004783 b73 m Flank Modifications in Bevel Gears Using a Universal Motion Concept Dr. Hermann
7、J. Stadtfeld Director, Research Pi . cutter tilt Pj . orientation of tilt ; Em . machine offset Xb . work base setting; Xp . center-to-back Z. machine root angle; Ra . ratio of roll O. roll position One problem in realizing the UMC correction concept was the computer simulation of the cutting proces
8、s which is necessary before the first advanced corrected gearing is manufactured. For computer tooth contact analysis, finite- element calculation or for providing a master gear for coordinate measurement, the theoretical flank surface is required. This must be described by discrete points anc norma
9、ls in a Cartesian coordinate system. Figure 3: Configuration generating gear - work gear for solving the gearing law -4- COPYRIGHT American Gear Manufacturers Association, Inc.Licensed by Information Handling ServicesSTD-AGHA 75FTM12-ENGL 1975 b87575 0004787 219 M _ c The most elegant solution for c
10、alculating the theoretical flanks is the application of the law of gearing in the basic gear cutting machine model. Apoint of a defined cutting edge generates a point and a normal on the generating gear flank. The arrangement of the generating gear to the work as well as their ratio (Figure 3) allow
11、 the solution of the gearing law (and therefore, a point and a normal of the work flank is found). The analytical solution of the gearing law is not single-valued. One of the solutions represents a point on an external tooth, another one a point on the mating internal tooth. Two other solutions are
12、either double solutions or an invalid complex solution. A single-valued solution of the law of gearing is possible with the vector representation of the gearing problem. In order to generate flank surfaces to be created by means of UMC motions, the vector approach was chosen. In all gear cutting met
13、hods widely used today, a limited solution of the gearing law was sufficient. In order to accommodate the additional UMC motions, a completely general formula had to be found for the vector approach. Apart from the rotation of the generating gear 0 = fi3 and the work R1, the rotation of the shaft an
14、gle fiz and the translatory movement along the three axes Tx, Tu and Tz3 must be considered. For the first time in gearing calculation, a completely universal solution was found, which does not need iteration. The vector ( 5 - C :. + - a (r; L - application types. the engineering bwing. file connect
15、ion to the CMMs. with target tooth contour data - 7. Quantification of the effects of manufaawing process variations in terms of loaded bevel gear set performance. TOE 13 ECL O S-AhCE NCCES robust. 9. Identification of tooth contour modifications in response to field (a) Nowptimum tooth contour or m
16、anufactunng problems. w! u? Design Notes 5 ci c The design process at Caterpillar is decoupled from the specific machining process to an extent. Machine settings are not required for the FEA analysis but are usually included through the conventional timeshare systems 1141. Experience with the design
17、 methods has been positive: considerable “cut and try has been eliminated, field experience has improved, and lead times for new designs has been reduced. Conclusions The conclusions have been drawn hm experience of seved years. Feature-based definition of bevel gear teeth has demonstrated the follo
18、wing advantages: 1. Increased engneering design accuracy 2. Better communication between engineering and manufacturing 3. Improved understanding of heat treat distoltions ) Optimum tooth contour 4. Data consolidation into a form manageable by SPC 5. Promotion of SPC techniques 6. Subsequent data to
19、idente opportunities to improve the process 7. Robust designs based on knowledge of process variabiliq Figure 16. Design of optimum tooth contour with FEA-based pro g r a m s (Maximum contact stress areas right hatched) 11 COPYRIGHT American Gear Manufacturers Association, Inc.Licensed by Informatio
20、n Handling ServicesReferences i. Eade Buckingham, Spur Ga McGraw-Hill Book Company, 2. Kaom Jshikawa, Guide to Ouali. tv Con!z,?l, Asian Productivity 3.Lowell W. Foster, Geo- Addison-Wesley Publishing 4. American Gear Manuhihirers Association, AGMA 390.03, Vol. 5.American Gear Manufacturers Associat
21、ion, ANSVAGMA 6. h4aag Gear Company Ltd., Inc., New York. 1928. Organization, Tokyo. 1982. company, inc., Reading, Mli 1990. 1, 1980. 2000-A88,1988. Zurich, 1990. 7.Darle W. Dudley, piacticalirear D a, MCGmW-Hill Book Company, Inc., New York 1954. 8.Theodore J. Krenzer and Richard Knebel, “Computer
22、Aided Inspection of Bevel and Hypoid Gears.“ SAE international Off-Highway & Powerplant Congress & Exposition, Milwaukee, September 1417,1983, Paper 831266. 9. AJ. Lemanski, “Advanced Measuring Technique fir In-Pmess Control of Spirai Bevel Gearing,“ AGMA Fail Technical Meeting, SanFrancisco, Octobe
23、r 14-16,1985. 10. RE. Brom and RO. Chamben, “Coordinate Measurement of Bevel Gear Teeth,“ SAE international Off-Highway & Powerplant Congress & Exposition, Milwaukee, September 14-17, 1987, Paper 871645. 11. Allan H. Candee, “Bevel Gears - Their Generation, Kinematics, andGeomeffy,“ . Volume 4,1954.
24、 12.AmrriCan Gear Manufacnirers Association, ANSVAGMA 13. Ford Motor Company, “Continuing Process Control and Process Capability improvement,“ Dearbom, MI, 1985. 14. Theodore J. benzer, Increasing Role for the Computer in Bevel and Hypoid Gear Manufacnue During the 1980s: AGMA Fall Technical Meeting, New Orleaas, October 11-13, 1982, Paper P129.25. 1012-F90,1990. 12 COPYRIGHT American Gear Manufacturers Association, Inc.Licensed by Information Handling Services
