RXP400DSC – 5‑axis Machine
Large swivel range up to 135°
- Highly precise micro-machining
- Electrodes, small moulds, watches etc.
Machines
RXP500DS – 5‑axis machine
Compact, highly dynamic, high-precision
5‑axis HSC machine
- With counter bearing and special Roeders geometry compensation
RXP500DSC – 5‑axis machine
Optimised geometry for better machining access in operations with large swivel ranges
- Inertia reduced further compared to the RXP500DS, therefore no break in the C axis
- Workpiece in the centre of the swivel axis
→ only small compensation movements by the linear axes - Special Roeders geometry compensation
RXP501DS – 5‑axis machine
Compact but rigid 5‑axis HSC machine
- Large choice of machining spindles
- With second bearing for swivel axis guaranteeing high stiffness
RXP501DSC – 5‑axis machine
C‑axis more eccentric compared to RXP501DS
- Better access to workpiece for large swivel angles
- With second bearing for swivel axis
guaranteeing high stiffness - No break for C‑axis
RXP601DS – 5‑axis machine
Highest possible dynamics through extremely powerful direct drives, also in the rotary axes
- Highly precise due to special Roeders geometry compensation
- Standard chucks, including UPC Erowa, may be integrated
- Machine fits into a standard container for transportation
RXP601DSH – 5‑axis machine
Highest possible dynamics through extremely powerful direct drives, also in the rotary axes
- Highly precise due to special Roeders geometry compensation
- Maximum workpiece size in height and diameter significantly larger than on RXP601DS
RXP950DSH – 5‑axis machine
Highest possible dynamics through extremely powerful direct drives, also in the rotary axes
- Highly precise due to special Roeders geometry compensation
- Strong rotary and swivel unit, identical with the one of the RXU1001DSH
RXU1001DSH – 5‑axis machine
With QUADROGUIDE for high roughing capacity, dynamics and precision
- All axes with direct drives
- Milling spindle may be chosen depending on the application, up to 102 Nm (S1) available
- Compared to the RXU1000DSH the travel in X‑direction and the maximum workpiece diameter are increased, the offset of the C‑axis is higher
RXU1001DBH – QUADROGUIDE
Special machine design for machining BLINGS and similar workpieces from two sides in one set-up
- With QUADROGUIDE for high stability and dynamics
- All axes with direct drives
- Milling spindle may be chosen depending on the application, up to 102 Nm (S1) available
RXU1201DSH – 5‑axis machine
With QUADROGUIDE for high roughing capacity, dynamics and precision
- All axes with direct drives
- Milling spindle may be chosen depending on the application, up to 102 Nm (S1) available
- Ideal for forging dies, mould and die making, aerospace industry, medical applications, machine production and part manufacturing
RXP400 – 3‑axis machine
Optimized for
- Micro-machining
- Minting technology
- Small steel moulds
- Electrodes
RHP Machines
The RHP machines differ from the RXP machines in terms of the guideway concept. Hydrostatic guideways in all axes improve the running performance significantly:
- Micro-movements across the travelling direction of the axes in the sub-micrometre range, as encountered with roller guideways, are reliably prevented.
- The controlled hydrostatic oil film between the moving slide and the guideways provides additional damping.
- The precise temperature control of the hydrostatic oil is effective directly at the guideways, prevents temperature fluctuations and hence thermally caused deformation of the machine geometry.
- Because the axis covers and weight compensation for the Z axis (patented) are optimised for minimum friction, the axes exhibit an ideal drive control response.
The fundamental technology of the RHP machines corre-sponds to that of the RXP series: linear motors in all axes, Roeders RMS6 control, exact temperature stabilisation, compensation of the spindle elongation etc.
- Hydrostatic axis construction with hydrostatic guideways pretensioned by the magnetic field of the linear motor
- High-precision glass scales with a position resolution of 1 nanometre
- Wear- and friction-free
Less micro-movements across the travel direction and therefore a much smoother running of the axis slide with hydrostatic guideways in comparison to guideways with roller or ball bearings
Options
The manifold options for the RXP series are also available for the RHP machines, e.g. rotary swivel units for 5‑axis machining etc. The RHP machines are excellently suited to the combination of HSC milling and grinding.
3‑achsig:
QUADROGUIDE – Extremely Stiff RXU Machines
Is it possible to design a machine with high stiffness, high dynamics and high precision?
QUADROGUIDE – a totally new concept combines those characteristics in an ideal manner. The transmission of the forces from the cutter along Z axis and Y axis into the machine body has been optimized with totally new machine design. Very high stiffness is achieved with low inertias.
4 guiding rails in the 4 corner edges of the Z axis transfer the acceleration and the machining forces with the means of 16 guiding carriages with high damping into a massive machine bridge.
Linear motors and modern drive technology enable the RXU machines for unprecedented dynamics and precision.
Spindles with more than 100 Nm torque (S1 operation) and 22,000 rpm allow a large variety of applications.
High roughing capacities in hardened steel or difficult to machine materials and highest surface qualities and precision are achieved in one set-up.
3 axes:
5 axes:
The RXP Machines
are the result of a long-lasting development process in Roeders HSC machine construction. With multiple patents and optimized in every detail, these low-wear and energy-saving linear motor machines achieve the highest possible precision, dynamics and surface qualities possible in numerous application areas.
3 axes:
RXP400
RXP500
RXP501
RXP801
RXP950
5 axes
RXP400DS
RXP400DSC
RXP500DS
RXP500DSC
RXP501DS
RXP501DSC
RXP601DS
RXP601DSH
RXP950DSH
Design Features of the Roeders Machines
Roeders’ machines are optimised for roughing and finishing operations on a wide range of materials (steel, aluminium, titanium, copper, carbide, ceramics, glass, graphite, etc.) using milling and/or grinding. The focus lies on highest precision, best surface finishes and shortest possible machining times. Complete processing in one single set-up, on 3- or 5‑axis machines, including deep-hole drilling and thread cutting, minimise throughput times. In many applications, reliable quality control can also be carried out by directly measuring in the machine. A machine technology that has been carefully thought through in every detail and is covered by multiple patents gives the machines their unrivalled performance and reliability.
The machines, which are exceptionally robust and heavy, are generally designed as portal structures, as this is the most precise design, albeit a more costly one. Low moving masses allow for high dynamic performance in all axes. Since year 2010, Roeders has been manufacturing only machines with direct-drive technology (linear and torque motors) in all axes. The machines are installed well-defined and without distortion on three machine feet.
As a pioneer in the development of linear motor machines, Roeders recognised at an early stage the importance of a friction-free weight compensation for the vertical Z‑axis that does not affect control accuracy, and developed a patented solution using vacuum hoses. These also have the advantage that no heat is generated, even during dynamic movements of the Z‑axis. This makes it possible to achieve extremely small positioning increments in sub-micrometre range in the Z‑axis without problems.
Roeders machines were initially developed for the company’s own mould making operations, so great care was taken from the very beginning to ensure a highly practical design. Generously sized windows and doors allow the operator to view and access the machining area from two sides. Automation is usually carried out from the front, so that for the automation the machining area is accessible via the front door, whilst the tool changer, located next to it, is accessible via a separate flap, allowing the handling system to automatically load workpieces and tools. Naturally, crane loading is possible on all machines.
The design of direct-drive axes with linear or torque motors is impressively simple and compact. Even a layperson can immediately see that axes with direct drives are the more precise and dynamic solution compared to ball screw driven axes, particularly if linear scales interpolated to a resolution of 1 nanometre are used. The minimal number of moving parts ensures an extremely low risk of failure and prevents wear. Roeders exclusively relies on highly rigid roller guideways. In high-precision applications, these can be temperature-controlled using a cooling circuit. Here too, Roeders was a pioneer.
Over several years of development, Roeders optimised the thermal behaviour of the machines, culminating in the PRECITEMP® technology. Numerous temperature-controlled circuits prevent thermally induced deformation of the machines, particularly due to internal heat sources such as the motors.
To ensure a high-precision control of the movement of the linear axes, it is essential to minimize friction as much as possible. That is why Roeders has relied for many years on bellow-covers with slats, which are virtually friction-free.
During tool changes, no chips should fall between the tool holder and the spindle shaft. Roeders therefore gives particular importance to chip protection during tool changes. There is always only one tool holder in the machining area at any time – the one that is currently being inserted into or removed from the spindle.
Spindles at Roeders
For a high efficiency of the machine in the user-specific application the spindle choice is essential. Therefore, Roeders offers an exceptional wide range of main spindles.
By means of a standardised interface, which has been optimised over many years, especially thermally, the main spindle is mounted in the Z‑axis of the machine. This allows for a cost-effective change to another spindle type at a later time, in case the application for the machine changes. Options like vector control, shaft cooling, rotary lead throughs etc. are available as needed. Roeders always has spare spindles in stock for all spindle types.
If an application requires very high rpm and, at the same time, a relatively powerful spindle, it is possible to equip the machine with two main spindles.
A typical combination of two main spindles is:
- Spindle 1: ball bearings, HSK E50 with 36.000 max. rpm
- Spindle 2: air bearings (highly precise), HSK E25 with 80.000 max. rpm
Automatic tool change, laser measurement, different cooling lubricants, 3D probes and, in the case of jig grinding machines, all the necessary functions such as dressing, sound detection-based measurements, etc. are available for both spindles.
Both spindles are integrated into the machine as close to each other as possible, whilst being temperature-controlled with high precision using multiple cooling circuits. This ensures that the distance between and the position of the spindles are kept absolutely constant, so that the highest possible zero-point accuracy is achieved when machining with both spindles.
The ‘Z2’ option is available on the RPT and RXU machines, as well as the RXP601DSH, RXP801, RXP950 and RXP950DSH.
The Roeders Drive Technology
The drive control of the axes is crucial to machining results, in terms of both precision and surface finish. With control cycle frequencies of 32 kHz, Roeders has been setting the standard for years. Oversampling for encoder evaluation and numerous other specialised functions ensure the highest possible axis accuracy, whilst also minimizing energy consumption.
The performance of the control technology can be measured very easily, for example by means of a circularity test, in which Roeders machines consistently achieve top results in the sub-micrometre range.
Roeders’ precise control technology is not limited to the NC-control and the control units for the axes. The temperature of the cooling water for the machine is also maintained at a constant level with a very low hysteresis of less than 0.1 K. Where very high standards are required, the hysteresis is even less than 0.02 K.
Thanks to Roeders’ control technology and high-precision optical encoders in all axes, minimum positioning increments of 10 nanometres can not only be programmed but also achieved in the individual axes.
Contrary to many rumours, linear motors are energy-efficient when used with optimal control technology, particularly when compared to machines with ball screw drives in the axes. Lower friction in the axes means less heat is generated and, consequently, lower energy consumption.
The Roeders Control RMS6
The Roeders RMS6 machine control system has been continuously developed and improved since 1994 to meet the most demanding requirements for precision and surface quality in milling and grinding. The open and robust control system is based on two PC-based industrial computers. A 21,5” TFT screen is standard. The few control elements are arranged in a very clear and logical manner. Running on Microsoft Windows, the user interface is easy to operate and requires only a very short training period. Numerous features, some of which are patented, have been integrated into the RMS6 specifically for milling and grinding. Post-processors for standard CAM systems are available. The RMS6 processes Heidenhain® and ISO program code.
Vibration monitoring of the spindle
The use of high-speed spindles requires a limitation of the maximum spindle load in order to avoid bearing damage or a severe reduction in service life. Optionally, the spindles can be equipped with vibration sensors. A function in the control can be activated that automatically reduces the feed and, if necessary, the RPM of the spindle in the event of high vibrations. In addition, a coloured graphic illustration of the vibrations along the milling path is possible. As a result, any areas in the milling path with high vibrations can easily be identified and can safely be avoided in recurring machining processes by adapting the CAM programming.
Compensation of spindle elongation
Roeders machines have been known for years for their external high-precision sensor for compensating the spindle elongation . A holder fixed in the casting of the Z‑axis and kept geometrically stable with a temperature-controlled circuit carries a sensor at the end that contactless measures the displacement of the rotating spindle shaft in nanometre range. This is compensated for in the control system. Since the heat from the spindle shaft is transferred into the tool holder and it also lengthens as a result, a short warm-up phase had to be programmed for high-precision machining applications before starting the machining operation.
Meanwhile, the Roeders technicians have succeeded in modelling the dynamic heating process directly after the spindle has accelerated to full RPM, so that with the new option Spindle Compensation PLUS a warm-up phase can be skipped completely in many applications.
Roeders is partner of the umati initiative of the German machine tool association VDW (umati = universal machine tool interface). The umati interface enables a standardised data transfer with the machines of numerous suppliers. umati is an essential step towards industry 4.0.
The development of the RMS6 focuses on an optimised machine control during the production of free-form surfaces and complex contours. The RMS6’s performance is correspondingly outstanding, with block processing times of less than 0.1 milliseconds and a lookahead of over 10,000 blocks. The spline interpolation along the toolpath specified by the CAM system is continuously refined down to the nanometre range. A smooth and harmonious toolpath ensures optimum machine behaviour.
All Roeders machines supplied since 1995 can cost-effectively be upgraded to the latest RMS6 control version due to the PC-based control hardware. This also makes older machines more precise and faster in their machining operations. Furthermore, the full range of newest RMS6 functions is available. If a customer uses several Roeders machines built in different years, it is easily possible to operate all machines with the latest – and therefore identical – RMS6 version.
A dual-screen option is available for the RMS6, for example, if the operator wishes to have the editor, design views of the workpiece or drawings open alongside the control system’s menu structure and status window.
The vibrations of the main spindle do not necessarily increase steadily as the rpm rise. Depending on resonances, there are ranges with higher and lower vibration levels. For the machining process, exact rpm usually are not essential. With the automatic vibration optimisation, the RMS6 selects, within an rpm range specified by the operator, the rpm at which the spindle with the toolholder and tool clamped has the lowest level of vibration.
To avoid steps in transition areas that are machined using different tools, the RMS6 allows a setting to be specified whereby the edges of the machining areas are raised in such a way that a tangential transition is created between areas machined with different tools.
Post-processors are available for all leading CAM systems. A detailed post-processor manual is provided to optimise the interface between the RMS6 and the CAM system. In particular, for automated machine operation, machining programs can be generated reliably within the CAM system without the need for manual parameter input.
The RMS6 offers a high degree of flexibility when processing NC-programs for machining a workpiece. ISO (G‑code) and Heidenhain® NC-programs are possible and can also be used in combination. In addition, there is a considerable range of additional commands, extending standard NC-code as far as Basic-like programming, which opens up a wide range of possibilities, particularly for automation in specialised applications. Further commands can be added at customer’s request.
There are numerous strategies for the optimal use of tools, depending on the application. These relate to wear criteria, tool life and sister tools as well as measurement strategies, geometry recognition and inspection. To avoid the time-consuming task of entering tool data manually, a tool database is available, as is the option to import tool data and types.
With RACECUT®, Roeders has once again achieved a performance boost for machining. This functionality in the RMS6 drastically reduces machining times by up to 20 per cent without compromising quality. It is based on further improvements for tool path planning within the control system and a drives control system operating at a frequency of 32 kHz. As the machine’s energy consumption remains relatively constant regardless of the selected dynamic settings, the energy savings are of a similar magnitude.
#Heidenhain is the registered trade mark of the Dr. Johannes Heidenhain GmbH.
Double Spindle Machine – Option “Z2”
In some applications the choice of the main spindle is difficult, because either the maximum RPM of the main spindle is not sufficient or the maximum tool size allowed in the spindle is not large enough. This affects especially applications with optical surface quality or jig grinding, in case very small radii, for example in small holes, are to be machined with very high rpm, but also where larger tools are required for other operations.
In such cases, Roeders offers the possibility to equip a machine with 2 main spindles, one more robust for larger tools and one with high rpm, for example:
- Spindle 1: with ball bearings, HSK E50, 36,000 rpm max.
- Spindle 2: with air bearings, HSK E25, 80,000 rpm max.
Both spindles are fully integrated in the machine so that the automatic tool changer, laser measurement, different coolants, 3D touch probe and in jig grinding machines all of the equipment for dressing, sound detection etc. are available for each spindle.
The axes of both spindles have a short distance to each other, but the spindles are highly precisely tempered with several cooling circuits. This ensures that the distance between the spindles and the positions of the spindles remain absolutely constant. As a result, in applications where both spindles are used a very high consistency of the work piece origin is achieved. Two spindles are utilized for one work piece set-up.
The option “Z2” currently is available for the machines RXP601DS, RXP601DSH, RXP801, RXP950, RXP950DSH and for all RPT and RXU machines. In the RPT and RXP machines the distance between the two spindle axes is 150 mm, in the RXU machines the distance is 225 mm.
Other machine models may be equipped with two spindles upon request.
Tool changer for two main spindles with different HSK holders