Measurement strategy for countering the burden of time

When it comes to complex gear measurement, slow processes and high programming expenditure can eat away at your patience and efficiency. At WEISS GmbH, the gruelling burden of time has been eliminated thanks to an intelligent measuring configuration – the Leitz PMM-F and Leitz Reference high-performance coordinate measuring machines (CMMs) from Hexagon Manufacturing Intelligence, can be used simultaneously as gear measuring centres.

Rotary tables, handling components and linear transfer systems are the most important elements of linking technology in industrial production processes. It’s a technology largely shaped by the products of WEISS GmbH, a company located in Buchen, Odenwald. This company is an internationally leading supplier of automation solutions, from rotary tables to part-handling systems.      

At the heart of almost every WEISS product is the cam drive, which enables fast switching operations with optimised, soft and smooth motion sequences. The massive driving force is translated into fine rotational motor movements of the rotary indexing table and parts of the linear assembly system through the thread and gear wheel of the cam.

That’s why we need to scrutinise this component particularly closely, explained Quality Manager Marius Grosse, who also highlighted that WEISS’ vertical integration is nearly 100%. With product diversity increasing new measurement orders are added to the agenda almost every minute.

Growing requirements for precision and speed

About two years ago, it became apparent that WEISS would not be able to tackle this task for much longer using the existing coordinate measuring technology available. First and foremost, it was the expenditure required for gear measurement on a separate gear measurement device which upset the balance between time and efficiency, as the cam drives had to be tested in two separate runs: once on a gear measurement device and a second time on a coordinate measuring machine for the remaining geometry.

We were looking for a high-precision and extremely fast high-end coordinate measuring machine with a large measurement range which would also be an extremely powerful gear measurement centre for our cams, explained Marius Grosse.

They found what they were looking for twice over in the form of two Hexagon measuring machines capable of covering this requirement profile to the fullest: the Leitz PMM-F high-performance coordinate measuring machine and gear measurement centre and the Leitz Reference HP bridge measuring machine. For the past two years, these CMM’s have formed the centrepiece of quality assurance at WEISS.

Accuracy meets measurement throughput

With the Leitz PMM-F, accuracy meets high measurement throughput. This measuring machine is designed to test medium-sized components and gears, measuring both with maximum accuracy and a high throughput. The MPE-E value lies within a temperature range of 18° to 22°C at 2.3 + L/400 μm. Servo drives with ball screws, combined with an overhead gantry with minimal moving mass, enables measuring speeds which used to be unthinkable with machines of the same size.

In addition, the Leitz PMM-F offers a host of advantages in comparison to the previous conventional gear measuring device when it comes to gear testing:

• Greater flexibility, as not only gears, but almost all workpieces can be measured with great accuracy.
• The ability to work without a rotary table, meaning that laborious centring and alignment of the gears is completely done away with.
• Unbeatable part throughput thanks to the fully automatic measurement of many gears on a single pallet.
• Complete measurement of gears on long shafts up to 3000 mm.
• In conjunction with the QUINDOS software, all types of gears can be measured: cylindrical gears, straight and spiral bevel gears, cylindrical worms, stepping gears, coupling gears, gear racks, curvic couplings and lots more.

More than 30 options for gear measurement

At the present time, gear measurement at WEISS is primarily focusing on the second new high-end coordinate measuring device in stock: the Leitz Reference HP (High Precision). As a bridge-type measuring machine and gear centre with a moving gantry, it’s the ideal machine in its class for combining high accuracy with optimum measurement throughput, commented Harald Vater Measurement Technician.

Equipped with the Leitz LSP-S2 3D scanning system developed by Hexagon in Germany, the Leitz Reference HP offers both fast single-point probing for all typical measuring tasks, as well as high-speed scanning for form and profile measurements. The deciding factor for WEISS: the Leitz Reference HP, paired with the QUINDOS software from Hexagon, also becomes a high-performance gear measuring centre with more than 30 specific measurement options.

QUINDOS represented a real quantum leap in gear measurement, a critically important activity at our company, stressed WEISS specialist Marius Grosse. To measure gears, only the respective parameters need to be entered. All traversal paths, probes and scan lines are generated automatically.