Power tool
Power tools are aids with which the operator of a lathe can perform milling or drilling work. The term stands in contrast to conventional fixed tools for turning , which only have to be guided because the workpiece is being driven. Driven tools are required for the complete machining of workpieces if, in addition to turning, milling or drilling outside the turning center is also required.
The following cutting tools are used : milling cutters , countersinks , drills , taps , reamers , rarely a circular saw blade or slot cutting units.
Function and designs
In contrast to the fixed tools, the driven tools consist of a unit of tool and drive, so they need their own energy supply. They must be clamped in a tool holder for guidance. There are tool clamping systems that can accommodate both fixed and driven tools.
When using the controlled movement of the work spindle (C-axis) and driven tools, workpieces can be provided with grooves , cross bores, hole circles , millings and engravings in one clamping in addition to normal turning . The higher the expansion level of the machine tool, the greater the possibilities for machining complex geometries (Y / B axis). A three-axis path control and a tool turret with a motor that drives these tools allow complete machining of workpieces without reclamping or with reclamping and rear side machining. Processing speeds up to 60000 min -1 are possible with appropriate mechanical equipment.
The tool holders of the driven tools are supplied for axial or radial machining, off-axis, shortened or set back, with internal or external coolant supply , different gear ratios, angle-adjustable designs or even multi-spindle technology .
They are produced for the different interfaces on the lathes, with different shanks and tool holders : collet chuck , milling arbor , Weldon , circular saw blade , as a quick-change system, etc.
Depending on the requirements, tapered roller bearings or spindle bearings , needle bearings or needle sleeves , deep groove ball bearings or thin section bearings are installed in the inner part .
The seals are selected according to the specific requirements of the machine, up to approx. 80 bar. The standard range is 16 bar; the high pressure area at approx. 250 bar for the supply of cooling lubricant to the tool cutting edge.
Today, the true running accuracy of the tool spindle is in the order of magnitude of <0.005 mm.
history
Driven tools were developed with the conversion to CNC lathes from around 1980. With the introduction of the CNC lathe and the development of a new lathe turret, it was possible to reliably manufacture complex parts that required turning and milling work on the lathe in a single operation.
With the introduction of complex controls, it was possible to only produce such parts on the lathe instead of using a lathe and then a machining center or milling machine .
literature
- Ulrich Fischer (Ed.): Metal expertise. 52nd edition, Europa-Lehrmittel, Haan-Gruiten 1996.
Individual evidence
- ↑ See: Heinz M. Hiersig : Lexicon production engineering, process engineering . Springer, 1995, p. 172.
- ↑ Heisel, Klocke, Uhlmann, track: Handbuch Spanen , Hanser, 2014, 181f.
- ↑ Werner Bahmann: Machine tools compact. Assemblies, use and trends . Springer, Berlin 2013, pp. 101-102, ISBN 978-3-658-03748-2 .
