Gear Production Using Hermle Five-Axis Machining
Geo Kingsbury Machine Tools has revealed that gears can now be manufactured on Hermle five-axis machining centres following a tie-up between the machine tool builder and software firm HPG. Geo Kingsbury Machine Tools, Hermle's sole UK agent, has described the process, which is ideal for producing small batches of gears and even one-offs in the size range 500-1,200mm diameter.
The five-axis milling technology allows precision roughing and super-finish machining of gear teeth and other complex 3D contours on a Hermle machining centre, either a C 40 U or C 50 U fitted with a Heidenhain iTNC 530 or Siemens 840D control. The set-up time required for multiple machines used in conventional gear production is avoided, allowing economic production of small quantities of gears and enabling the generation of special tooth profiles that could not otherwise be produced.
Using HPG's software, a gear can be completely machined used standard milling cutters on a Hermle. Via an online connection to an HPG-licensed service provider, gear geometry data such as module, diameter, tooth width and height, contact area ratio and crowning is transmitted. On the basis of this data, the software performs the mathematical calculation for the exact tooth shape, which is developed as a point cloud and translated into an NC program for milling the gear. After the roughing cycle, the component is sent for hardening, after which it is returned to the machining centre for finish milling.
It is then measured in situ, the data is compared with the CAD model and, if necessary, a few ultra-fine finishing passes are completed to bring the gear into its designated quality class (one to 12). This will depend on its intended use, for example, in the transport, power generation, mining or construction equipment sectors. High-resolution mathematical calculation as described is the best route for high-quality gears, say classes two or three, whereas quality classes five to seven are best obtained by producing the gear machining cycle conventionally from the CAD model. HPG performs mathematical tooth-shape modelling, allowing its customers to achieve much higher resolution than is possible based on CAD data alone.
Almost any tooth shape can be machined to a high degree of precision, resulting in good efficiency of the gear sets and leading to quiet operation and long service life. The gear production method, using standard five-axis machining centres and tooling, coupled with HPG's program generation software, can even produce gears with cosine ('S'-shaped) or other complex tooth profiles. Therefore customised gear teeth can be manufactured without the need for expensive special equipment.
The five-axis milling technology allows precision roughing and super-finish machining of gear teeth and other complex 3D contours on a Hermle machining centre, either a C 40 U or C 50 U fitted with a Heidenhain iTNC 530 or Siemens 840D control. The set-up time required for multiple machines used in conventional gear production is avoided, allowing economic production of small quantities of gears and enabling the generation of special tooth profiles that could not otherwise be produced.
Using HPG's software, a gear can be completely machined used standard milling cutters on a Hermle. Via an online connection to an HPG-licensed service provider, gear geometry data such as module, diameter, tooth width and height, contact area ratio and crowning is transmitted. On the basis of this data, the software performs the mathematical calculation for the exact tooth shape, which is developed as a point cloud and translated into an NC program for milling the gear. After the roughing cycle, the component is sent for hardening, after which it is returned to the machining centre for finish milling.
It is then measured in situ, the data is compared with the CAD model and, if necessary, a few ultra-fine finishing passes are completed to bring the gear into its designated quality class (one to 12). This will depend on its intended use, for example, in the transport, power generation, mining or construction equipment sectors. High-resolution mathematical calculation as described is the best route for high-quality gears, say classes two or three, whereas quality classes five to seven are best obtained by producing the gear machining cycle conventionally from the CAD model. HPG performs mathematical tooth-shape modelling, allowing its customers to achieve much higher resolution than is possible based on CAD data alone.
Almost any tooth shape can be machined to a high degree of precision, resulting in good efficiency of the gear sets and leading to quiet operation and long service life. The gear production method, using standard five-axis machining centres and tooling, coupled with HPG's program generation software, can even produce gears with cosine ('S'-shaped) or other complex tooth profiles. Therefore customised gear teeth can be manufactured without the need for expensive special equipment.
Comments