Pushing into new territory
Released on 10/10/21
- Broaching of all kinds of shapes, such as toothing, hexagon socket, torx or grooves
- Machine-friendly broaching movement via the turret drive and extender
- Machining in one setting, post-processing not applicable
Breaking into new territory
Broaching on a lathe? This thought makes many a machinist's hair stand on end. CNC unit manufacturer BENZ Werkzeugsysteme has developed "LinA", a machine-friendly broaching unit that can broach toothing with high precision on a TC35 Y from CMZ.
The idyllic Black Forest Kinzigtal is not only known for cuckoo clocks and “Bollen-hats”, but also for innovative tooling solutions: In Haslach, BENZ GmbH Werkzeugsysteme produces CNC aggregates for the metal and woodworking industry. Founded by Xaver Benz shortly after the end of the war in 1946, the company initially manufactured technical components for agriculture. With the rise of CNC technology in the 1980s, BENZ was one of the first to offer angle heads and driven tools for CNC machine tools in metal processing, which gave the company an enormous growth spurt. In the 90s, units for the wood industry were added, which are now among the market-leading tooling solutions, just like the units in the metal sector.
In order to ensure a high degree of flexibility, BENZ relies on a machine park that enables the production of a wide variety of parts in small batch sizes. Therefore, there is not a single machine in production that is designed for high quantities or has automation. "Eighty percent of our batch sizes are between one and three," Huber explains. In the meantime, the machine park has grown to an impressive number of almost 30 machines of various brands. Older machines are regularly replaced by new ones.
A flexible lathe wanted
This was also the case towards the end of 2011, when Benz was looking for a CNC lathe with driven tools. "Our primary goal was to completely machine the parts on one machine. In the past, an entire machine park was used for this," says Huber. Due to the limited budget, production manager Huber thought of a used machine. However, the commercial agency responsible for BENZ, Haas Werkzeugmaschinen from Villingen-Schwenningen, recommended buying a new machine instead of a used one. "Our sales representative made us aware of the Spanish brand CMZ, but I had not heard of it before," explains Huber.
Machine-friendly broaching solution developed
The thought came up, why not adapt one of the latest developments - the BENZ LinA broaching unit, which enables broaching on the lathe - to the machine? Because the TC35 Y is ideally suited for this thanks to its robust design. Without further ado, the specialists from the BENZ innovation workshop also implemented this project.
The "LinA" broaching unit was originally designed as a groove broaching unit, but in the meantime, shaping of all types such as gears, hexagon socket or Torx is also possible. Unlike conventional broaching tools in lathes, the broaching movement on LinA is not carried out via the Z-axis, but we via the turret drive and an extender. "A broaching movement via the Z-axis would not do the machine any good and would be very wear-intensive," Huber explains. The speed range here is between 400 and 1,000 revolutions per minute and corresponds one-to-one to the stroke movement. The machine only has to provide the necessary speed and stability via the turret. A lift-off function ensures that the tool does not scratch the surface.
The advantage of the broaching unit is clear: workpieces can be provided with splines, grooves, etc. after turning - in a single clamping operation. This saves the user not only time, but also costs. There is no need for post-machining. "More and more machinists are discovering the potential that our solution can offer them," explains Michael Kempf. "The market for broaching on the lathe is still in its beginnings. We see ourselves as technology ambassadors here." Together with CMZ, BENZ will therefore show the broaching solution for lathes at the EMO in Hanover and answer questions from all interested parties.