Machine Building & Automation 2010 - Show Preview

Motors, gears and drives

Delta Line will be offering a wide variety of motion products as standalone components or as complete systems. These include: DC and brushless DC (BLDC) motors; disc magnet, hybrid or tin can stepper motors; spur gear, planetary and customised gearboxes; encoders and intelligent drives for DC, BLDC or stepper motors.

The display will include Portescap's new Athlonix brushed DC motors, which are compact, high-efficiency endurance motors that deliver exceptional speed-to-torque performance in a compact lightweight package with output powers of up to 9W. They are available in 12, 16 and 22mm frame sizes. Athlonix motors have motor regulation factors that are claimed to be 5-20 per cent lower than most comparative motors available today, resulting in consistent power density over the motor's life (see this article: Portescap Athlonix brushed DC motors for consistent performance).

Also on show will be the new nuvoDisc flat brushless DC miniature motors. These compact (32mm diameter by 11.7mm long) motors are described as offering superior continuous speed, quick design integration and mechanical installation, and high reliability due to no mechanical wear - as a result of the slotless, cog-free design, nuvoDisc motors benefit from minimal vibration (see this article: Portescap nuvoDisc flat brushless DC miniature motors)

Another highlight on Delta Line's stand will be the new DPM high-torque brushless 42 mm motor with integrated Hall sensors. The high-energy permanent magnets used in these BLDC motors produce very high efficiency and acceleration with a peak torque that can reach 1.44Nm. The 10-pole configuration of the stator increases the torque constant value up to 0.054Nm/A. This DPM range includes motors from 22mm diameter up to 86mm with a rated torques from 8mNm to 2.1Nm and in lengths of 40, 60, 80 and 100mm.

X-Y-Z systems

HepcoMotion is planning to use the 2010 show to challenge the view that any type of linear actuator can be chosen for any axis in an X-Y-Z system. The demands on each axis varies considerably so a 'one-type-fits-all' approach can compromise performance, reliability and the service life of the overall system (for more information, see this article about light- and medium-duty X-Y-Z systems).

On a specially developed demonstration unit, HepcoMotion will show that, with the correct choice of linear actuator, each axis will operate optimally. The company has developed a family of actuators to address the different characteristics required of each axis. And these elements can then be incorporated into a chassis made from HepcoMotion's comprehensive MCS machine construction system and given intelligent control through HepcoMotion's partnership with SmartDrive. HepcoMotion supplies it X-Y-Z systems as individual parts, in kit form or as fully assembled units.

The demonstration unit at the exhibition will feature a HepcoMotion PDU2 linear actuator operating as the X-axis, with a higher-specification PDU2M on the Y-axis. The needs of the Z-axis are different again, hence the new PSD80 is used here.

Plastic bearings

Igus is to show a new breed of hybrid linear bearing that both rolls and slides. The DryLin WJRM system is said to reduce driving force significantly and is particularly suitable for applications that combine sliding and rolling movements, such as manually adjustable doors, guards, partitions and locks, as well as for light handling tasks (see this article: Plain bearing units combine linear and rotary motion).

The lubricant-free plastic sliding plain bearings ensure the hybrid linear system is robust and insensitive to dirt and humidity, as well as being lightweight and cost-competitive. The polymer rollers, which are also maintenance-free, allow for easy manual adjustment of heavy machine doors and similar components that can weigh up to 50kg. At a defined installation position, the roller bearing, which carries the main load, reduces the overall driving force by a factor of between four and five to ease manual operation. The plastic sliders complement the rolling bearing by compensating for any lateral loads.

Igus has based the design of the new hybrid bearing around the DryLin W flexible modular system that uses hard-anodised aluminium profiles, diecast zinc housings, stainless steel or aluminium, and plastic plain bearings. The broad choice of options within this easy-to-install system enables engineers to optimise the available design space. Combined with different carriage lengths, the rail widths permit many combinations to be specified. The four design sizes range from 6mm to a shaft diameter of 20mm.

All the DryLin W guide systems are dry-running systems, which has the added advantage that they do not have to be serviced (relubricated or adjusted) during operation. The linear bearings are offered with the polymer sliding bearings in iglidur J or iglidur J200. Both of these materials offer low wear and low friction values. In addition, they are resistant to chemicals, help dampen vibrations and are impervious to moisture that might accumulate in humid environments.

Igus has designed the new DryLin WJRM system in such a way that the roller fits inside without increasing the overall design width of the DryLin W guide system, which remains at 18mm. Standard economic guide profiles can be used, which are available in three styles for 10mm diameter shafts - as individual rails or as double rails with centres spaced at 40 or 80mm, which provides for self-alignment of the bearings and rapid installation. The hybrid bearing housing is of blue-chromed die cast zinc.

Hexapod

Newport Spectra-Physics will be showing a high-performance six-axis Hexapod micro-positioning system. With DC servo motor-driven LTA actuators, the Hexapod features an innovative design of special anti-friction coated spherical joints and is claimed to provide more than five-times the rigidity and twice the load capacity of other similarly sized hexapods.

The Newport Hexapod electronic controller is a special version of the Newport XPS advanced multi-axis controller for the synchronised transformations from Cartesian input co-ordinates to the motion of the Hexapod legs. In addition, the XPS also provides advanced features including instrument-grade I/O, hardware-based input triggers, event triggers, high-speed on-the-fly data acquisition, fast TCP/IP communication, and integrated TCL programming language for on-board processes. All these features improve accuracy and throughput, as well as making the programmer's life much easier.

A useful feature of the controller is the way a virtual pivot point can be freely defined, enabling the entire co-ordinate system to be relocated at will. In addition, two user-definable co-ordinate systems are provided, called tool (which moves with the Hexapod) and work (a stationary co-ordinate systems). Incremental displacements are possible in either of these systems in Cartesian co-ordinates, and positions can be easily calculated from one system to the other by a function call. Such functionality is said to provide a new way of mastering Hexapod motions without the need for complex external co-ordinate transformations.

Power transmission and positioning

WMH Transmissions, a distributor and manufacturer of gears and related components, will be exhibiting a selection of standard and custom products. Recent additions to its range include Rotex and Bowex couplings (conventional, anti-backlash and clamp-hub types), the Rotex couplings and drive shafts being utilised when WMH manufactures Cardan shafts. Note that boring and keying is offered on a next-day service when standard bores are specified.

Other recently added products are the Hiwin XY tables. If required, WMH can also manufacture linear tables to customers' specifications, basing these around Hiwin ball screws, linear guides and rails. Hiwin rolled ball screws and DIN standard nuts are available from stock, and these can be machined on very short lead times.

In addition to the Hiwin products, WMH offers special and non-standard ball screws and nuts from Taiwan, with very competitive prices and short lead times.

Machinery Directive

MachineBuilding.net will be at the exhibition to meet exhibitors and visitors. Unless they have already requested a copy, visitors can also register to receive a copy of the MachineBuilding.net Guide to the New Machinery Directive 2006/42/EC.

About the event

Advanced Manufacturing UK 2010, being held at the Birmingham NEC on 27/28 April 2010, will incorporate these co-located manufacturing-focused events:

• Machine Building & Automation
• The Mtec Sensors, Measurement & Instrumentation exhibition
• VTX, Vision Technology - image processing and optical technology
• 3C, Contamination Control & Cleanrooms
• Practical Vacuum
• MEDTEC UK - raw materials, manufacturing technology and outsourcing for the UK's medical device manufacturing industry

Visit www.machinebuildingukshow.com for further details and to register for free entry tickets, as well as links to all exhibition websites.