Stäubli robots provide the ideal solution for injection moulding specialist

Citation

(2001), "Stäubli robots provide the ideal solution for injection moulding specialist", Industrial Robot, Vol. 28 No. 1. https://doi.org/10.1108/ir.2001.04928aaf.002

Stäubli robots provide the ideal solution for injection moulding specialist

Stäubli robots provide the ideal solution for injection moulding specialist

Keywords Injection moulding, Robots

The integration of multi-axis robots within the trade injection moulding sector is gaining pace as moulders increasingly realise the benefits of automation. Frequently, an initial reluctance to adopt multi-axis robot solutions stems from partial appreciation of the cost/benefit profile achievable by using the latest automation equipment.

One of the first injection moulding companies to appreciate the advantages of using multi-axis robots was W.H. Smith & Sons (WHS) of Minworth in the West Midlands. WHS installed its first robot ten years ago (and it remains in regular use today) (Plate 1) while it now boasts a complement of nine Stäubli robots with plans currently being reviewed for further additions in the coming months.

Initially, there was some scepticism regarding the use of multi-axis robots. WHS was conversant with simple pick and place robots which it built itself and used extensively alongside the moulding machines, but the more complex industrial robot was regarded as possibly too advanced, complex and difficult to justify. Working closely with Stäubli engineers and having the opportunity to evaluate an ex-display model in its own works convinced WHS that multi-axis robots provided the ideal solution to a number of manufacturing cell problem areas and could readily be integrated into its systems at a realistic cost.

Plate 1 W H Smith boasts a complement of Stäubli robots

The RX range of robots is particularly suited to these types of applications. The compact footprint allows installation in the confined spaces often encountered in moulding cells, directly alongside the moulding machines. The ability to run supply lines through the arm's centre was an added bonus, making it easier to rig in tight areas. As Greg Boden put it, "The Stäubli RX robot with its clean compact lines looks the part – it is rigid, solid and reliable".

RX robots feature high speed and acceleration and are capable of following complex trajectories even at high speeds. Joint speed ranges up to 1,125 degrees per second. The high degree of accuracy and repeatability make the RX ideal for the performance of detailed, meticulous tasks. At the heart of each RX robot is the patented, unique, JCS gearbox providing zero backlash and consistent performance. In essence, the embodiment of Swiss precision and reliability. They are compact, having a minimal footprint, and are suitable for floor, wall or ceiling mounting. The range includes models with load capacities from 1.5kg to 60kg with a reach at the wrist from 665mm to 2,135mm. The movement in six axes provides an extremely large work envelope. User friendly software permits easy programming as well as re-programming to bring the added degree of flexibility often of benefit in automated systems.

The robots are engaged at WHS on a variety of tasks in the moulding cells from insert loading and packing of commutator parts for Black & Decker electric motors to demoulding, trimming and palletising of automotive components. The introduction of robot handling into the manufacturing line for car heater control knobs significantly improved quality by avoiding rejections caused by surface damage.

The response from the shopfloor has been equally positive, with demand coming from operators to install automation to improve utilisation and efficiency and place the tedious repetitive jobs under robot control.

WHS, which is still a privately owned business, has grown dramatically since its foundation in 1933. The company now supplies a complete service from technical support in the initial product design leading on to tool design and manufacture, injection moulding, assembly and decoration, to a wide range of multinational companies, in a variety of market sectors. From its Minworth site in the West Midlands, employing over 400 people, WHS will achieve a sales turnover of £24 million this year, with well-known names like Black & Decker, Toyota, Mars Electronic and TRW heading the customer list.

Unusually, WHS has an in-house engineering team who design, develop and build the manufacturing systems required, incorporating robotics where necessary. This team is also able to re-engineer systems, allowing the reuse of robots for new jobs; some of the robots currently in use are on their third application. One example is a robot initially used for demoulding, which was reprogrammed to work on packaging and is now glue laying on Honda timing belt covers. This design and development facility has been instrumental in moving WHS into an ever increasing range of secondary and ancillary operations, including the manufacture of its own printed circuit boards as well as crafting leather covers onto a range of top quality automotive fittings.

Future installations being considered by WHS involve the creation of flexible moulding cells incorporating Stäubli RX robots, which will be capable of switching production easily between a number of applications as the demand requires and also be easily reprogrammed to accommodate new components as the business develops. Boden and his team are confident that they now have the knowledge and experience to develop their use of robots in this way. They are also aware that, should they need it, there is a wealth of help and assistance immediately available from the Stäubli team at Telford.

It is only through the increasing willingness of businesses like WHS to fully evaluate the feasibility of using multi-axis robots and the quality of support available from Stäubli, that the UK's relatively poor performance on the use of robots in manufacturing will be improved.

For additional information contact: Mr Simon Whitton, UK Sales Manager – Industrial Robotics, Stäubli Unimation Ltd, Stafford Park 17, Telford, Shropshire TF3 3DG, UK. Tel: +44 (0)1952 290276; Fax: +44 (0)1952 290057; Web site: www.staubli.com