[雙語翻譯]齒輪設(shè)計外文翻譯--錐齒輪切削中齒輪設(shè)計對刀具載荷的影響（英文）

1、 Procedia CIRP 1 ( 2012 ) 66 – 71 Available online at www.sciencedirect.com2212-8271 © 2012 The Authors. Published by Elsevier B.V. Selection and/or peer-review under responsibility of Professor Konrad Wegene

2、rhttp://dx.doi.org/ 10.1016/j.procir.2012.04.010 5th CIRP Conference on High Performance Cutting 2012 Influence of Gear Design on Tool Load in Bevel Gear Cutting Fritz Klockea, Markus Brumma, Stefan Herzhoffa* aLaborato

3、ry for Machine Tools and Production Engineering (WZL), RWTH Aachen University, Germany * Corresponding author. Tel.: +49-241-80-28472; fax: +49-241-80-6-28472 .E-mail address: s.herzhoff@wzl.rwth-aachen.de. Abstract Dur

4、ing gear design, the tooth geometry is optimized towards the required running behavior. Pressure angle and tooth root radius of the gearset are among the influencing factors. As the tools in bevel gear cutting are specia

5、lly designed for each gearset, the tool profile geometry is defined by the gear geometry. The objective of this work is to analyze the influence of the tool profile geometry on thermal and mechanical tool load during bev

6、el gear machining. By means of a finite element based machining simulation the chip formation in bevel gear cutting of ring gears is calculated. The simulation results show a significant thermal and mechanical load maxim

7、um at the tool corner, where the maximal wear occurs. The variation of the tool profile geometry shows a high influence of the tool pressure angle and the tool corner radius on the tool load at the tool corner. © 2

8、012 Published by Elsevier BV. Selection and/or peer-review under responsibility of Prof. Konrad Wegener Keywords: Gear Cutting, Chip Formation, Machining Simulation, Tool Temperature, Tool Stress, Wear 1. Introduction an

9、d Challenge Bevel gear cutting is a very productive machining process, especially in automotive applications. A ma- chine kinematic in six axes is necessary to manufacture the gear geometry. In typical applications, th

10、e unde- formed chip cross-section is L-shaped, spreading over two adjacent cutting edges including the tool corner as shown in Fig. 1. In this multi-flank chip formation tools often reach the tool life due to excess

11、ive wear at the tool corner radius [1, 2, 3, 4]. This local wear limits the usable tool life in series production. Furthermore, tool wear related problems cannot be considered during the design phase of bevel gears.

12、This would require a model for tool life prediction which considers the tool profile geometry, which is not available. A model for the prediction of tool corner wear in bevel gear cutting inherits high potential for

13、process optimization. Tool wear depends on the strength of the cutting edge as well as on the thermal and mechanical load on the cutting edge during chip formation. As the tool load cannot be measured locally, a fini

14、te element based ma- chining simulation is used to model the process of chip formation in bevel gear cutting. The machining simula-tion is able to calculate the temperature and stress distri- bution along the cutting ed

15、ge. This approach of tool wear prediction based on tool load is new for bevel gear manufacturing. vc vfToolRing GearPinionZFBevel Gear Set900 μmTool WearMulti-Flank Chips© WZL Fig. 1 Multi-Flank Chip Formation in B

16、evel Gear Cutting © 2012 The Authors. Published by Elsevier B.V. Selection and/or peer-review under responsibility of Professor Konrad WegenerOpen access under CC BY-NC-ND license.Open access under CC BY-NC-ND licen

17、se.Fritz Klocke et al. / Procedia CIRP 1 ( 2012 ) 66 – 71 684. Simulation Results The simulation model has been used to calculate characteristic key values for the thermal and mechanical tool load in bevel gea

18、r cutting. Furthermore a variation of tool profile geometry has been done, which results are described in this section. In tool load analysis, two reasons for uneven load dis- tribution have to be distinguished. At fi

19、rst, an uneven chip shape will result in uneven load acting on the cut- ting edge, as discussed in [7]. Secondly, the shape of the cutting edge will influence the load occurring in the inside of the tool as well. For

20、example, a force at the tip of the tool will result in a three dimensional stress distri- bution throughout the tool. Hence, the analysis of the external load at the tool is not sufficient to qualify the tool load. Th

21、erefore internal load types, for example cutting edge temperature or stress state along the cutting edge, are analyzed in this paper. For the presentation of the results, thermal and me- chanical load values are cons

22、idered separately. At first, the internal load state is analyzed for one simulation, based on: ? temperature distribution along the cutting edge ? thermally affected volume of the cutting edge ? equivalent von Mises

23、 stress along the cutting edge ? mechanically affected volume of the cutting edge Afterwards, key values for the volumetric internal load distribution are derived by calculation of the prod- uct of the affected volume

24、 and the temperature or von Mises stress. Based on the volumetric key values the influence of the tool profile geometry on the tool load is shown. 4.1. Thermal Tool Load In Fig. 3 the temperature distribution and the

25、 thermal- ly affected volume of the cutting edge are shown. In order to determine the temperature data, the cutting edge is separated into different sectors. For each sector, the maximum nodal temperature is chosen, a

26、s shown in the upper part of Fig. 3. The volume VS? has been defined as the sum of the volumes of all elements of the FE-net, whose temperatures have exceeded ? = 323 K. The temperature of ? = 323 K has been chosen t

27、o define a thermal effect, as the simulation starts at room tempera- ture of ? = 293 K. In the upper diagram of Fig. 3 the thermal load over the unrolled cutting edge is shown. The x-axis represents the unrolled cutt

28、ing edge, starting at the flank cutting edge and ending at the end of the tip cutting edge. On the one hand, the diagram shows the temperature distri- bution after a cutting time of tc = 3 ms in the cutting edge and a

29、t the bottom of the chip. On the other hand, the volume VS? of the cutting edge, which exceeded a temperature of ? = 323 K, is shown. The lower diagram of Fig. 3 shows the development of the maximal temper- ature along

30、the cutting edge as mean value for the three sections of the tool over the cutting time tc. After the first millisecond of cutting time an eventemperature distribution along the cutting edge is estab- lished, as shown

31、in the lower diagram of Fig. 3. For explanation of this behavior two influencing factors have to be considered. At first, the flank cutting edge has the first contact to the tool and is therefore affected by the thermal

32、conditions of cutting for the longest time. The end of the tip cutting edge is the last part of the tool to get in contact with the workpiece. Secondly, the temper- ature difference of two bodies is the driving force for

33、 heat transfer. The temperature at the bottom of the chip is shown in Fig. 3 as dotted line. It shows that the tem- perature at the tooth root part of the chip is higher than the temperature at the tooth flank part. The

34、temperature difference between tip cutting edge and tooth root chip is larger compared to the temperature difference at the flank cutting edge and the tooth flank chip. Both factors combined explain the even temperature

35、distribution at the beginning of the cut. From there on, a significant temperature maximum occurs in the region of the tool corner, as shown in the upper diagram of Fig. 3. Fig. 3 Thermal Load at the Cutting Edge The the