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Title: Projects and developments Pages: 54 - 55  
Author: Editorial Text: Projects and developments Smooth sander The SPF Speedsander abrasive-belt sanding machine, which Thomas White & Sons of Paisley, Scotland, introduced at the Machine Tool Exhibition at Olympia last month, incorporates a number of advanced design features. It is also the first tool to be developed by the company's design team,under its chief design engineer James McNair, with the help of an industrial designer - Alan Anderson, from the Anderson Bonar & Morrison consultancy of Glasgow. The company believes that the clean, uncluttered appearance of the sander achieved by the industrial designer will help sales in Europe, where customers are often critical of the appearance of British machines. The machine has three main elements: a louvred base structure containing the main frame upon which the machine is built, the electric motors, and the controls; the conveyor table on which work passes through the machine; and the box-like structures above which covers the abrasive belt rollers, tensioning mechanism etc. The machine can handle wood, asbestos cement panels, composition flooring and some metals, and work is fed into the machine on an endless belt of rubber covered canvas; this carries it under the sanding roll, which sands down to a pre-set size, and subsequently under an independently adjustable finishing pad, thus enabling a good finish to be achieved after a single pass. The sanding roll or the finishing pad can be used independently and it is the gain in versatility due to the design of the finishing pad which is the machine's special engineering feature. When it is used for finishing only, the conveyor table floats on a pneumatic cushion, but for thickening it is firmly locked into position. A 40-hp motor provides ample power and feed speeds from 30 to 100 fpm can be selected with one of the two handwheels on the side of the machine; the other adjusts the whole sanding head up or down to set thickness (work up to 5 inches thick can be accepted). The start and stop controls are neatly housed beside these hand wheels but the emergency stop button is sensibly placed beside the conveyor table, where the operator is likely to be standing in any emergency situation. A prototype SPF Speedsander was exhaustively tested in a customer's factory before the machine was finally put on to the market, and 12 have now been sold. Since the machine fits neatly into the middle of the company's range of abrasive belt sanding machines, there are now high hopes that it will achieve the European sales expected of it. And since the company also exports many other machines for the woodworking and metal-working industries, perhaps it will now continue to use industrial designers, both to improve the styling and ergonomics and to develop a family likeness throughout its products. Road breaking made quiet An exercise at the Building Research Station, reported in DESIGN 225/21, showed that it is possible to reduce the noise of road drills by up to 40 per cent. Now a similar improvement has been made to a road breaker which incorporates two road drills linked to a central power source - designed by Williams & James (Engineers) Ltd and sold by Sonomotive (Sales) Ltd. As with the road drill, this modification was successfully achieved by making reduction in noise part of the designer's brief. In the case of the road breaker, the improvement has been made possible by abandoning the conventional pneumatic techniques and adopting, instead, a hydraulic system originally developed during the First World War. The system was coupled with a synchronising gear to enable machine guns to shoot through propeller and it was realised that, if the system could be built to handle greater forces than were needed to trigger a gun, it could transmit power via a pulse surging through a practically undisturbed hydraulic medium. And this is what the road breaker does. Instead of using a noisy compressor to provide intermittent surges of power to conventional pneumatic drills, the Sonomotive breaker has a Ford Cortina engine (converted to run off propane gas, thus eliminating toxic fumes) which runs at a constant speed and powers a sonic generator. This may be likened to a ram pump without valves, and on each revolution a pulse is created with a form similar to a sine wave and is transmitted through a hose to the piston of each road-breaking gun; this, in turn, strikes the breaker tool (chisel, tamper or whatever is fitted) at the same frequency as the pulses. The piston, in fact, is the only moving part of the gun, and is permanently sealed in a bath of oil. Thus the only noise emitted (apart from that of the Cortina engine) comes from the impact of the piston, and the bit of the gun breaking up the road, while the explosive sound of compressed air being suddenly released from the exhaust ports of pneumatic drills has been completely eliminated. Besides cutting down noise, this design of a breaker has increased reliability by reducing the number of working parts and using a well tried industrial engine which is backed by a comprehensive after sales service. The breaker is no more expensive than its pneumatic counterpart, and is claimed to be cheaper to run. Since it has already aroused the interest of one of Britain's major plant hire operators, and has been demonstrated through the good of offices of a local authority, it may not be long before people will stop and stare at a new phenomenon -a really quiet road breaker. Capsule kit for survival At Beccles, Suffolk, a small British engineering company, Elliott & Garrood, has joined Life Spheres Co of Beverly Hills, California, in the development of a revolutionary life craft. And although the craft- called the Brucker survival capsule after its inventor, Milton Brucker - has yet to be approved by the Board of Trade and the American Coast guard Service, its chances of being officially recognised have been increased by the Gas Council's recent order of four capsules for use on oil rigs in the North Sea. The capsule has a glass fibre pumpkin - shaped shell and can hold up to 28 men, who enter through two sliding doors in the top. Once they are inside, the capsule is automatically dropped off a ship, oil rig or what ever the craft may be, and plummets into the water, where it rights itself from any angle up to 125ø. With the doors shut, it cannot be swamped or dragged down by a sinking ship. Once on the water, the capsule protects its occupants from a wide variety of dangers. Besides eliminating exposure from cold and heavy seas, it can withstand severe impacts from ships' hulls or metal platform stanchions, and is able to survive the rigours of an oil slick fire for up to an hour, while water jets spray the capsule's hull to keep it cool. The capsule is also fitted with a 40-hp Perkins diesel engine which gives a speed of 3.2 knots for 24 hours. Besides enabling the capsule to get away from a danger area, the engine also provides heat, and uses a snorkel system to draw in air. Because of its tapering skirt, which dampens pitch, roll and yaw movements, the capsule remains stable even under severe weather conditions, and the chances of its occupants being picked up out of the sea are increased by its radar-reflecting skin and various homing devices. Weighing 5,500 lb and costing £18,750 as a complete, fully equipped system, the capsule compares favourably with the conventional lifeboat fitted on ships, while offering considerably better protection. Altogether, 50 capsules are on order, and their successful use on oil rigs could lead to their widespread use on ships as well. (caption) The drawing shows 1 periscope; 2 water sprinkler; 3 air exhaust chamber; 4 storage; 5 seats; 6 circular stabiliser. |
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