Servo drives signal a step change

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1 Every few years it is possible to observe a step change in the packaging machinery industry, indicating a wholesale change in direction for a particular type of machine. But a step change is not the first report of a new idea or the first application of a new technology. New ideas come thick and fast and it is not always possible to spot the really significant innovations when they first appear. To be honest, it is usually only with the benefit of hindsight that a particular innovation can be judged truly significant, or just another good idea which in practice didn t quite live up to expectations. The confirmation that an innovation is significant comes when several leading manufacturers pick up on a pioneer s bright idea and simultaneously launch new machines incorporating the new technology. To put it another way, observing new packaging machine inventions is usually like watching birds flock in the sky. Most of the time their direction appears to be random, but when they all turn and head off in one direction together, you know something significant is going on. A step change has occurred. We observed just such a step change in 1993 (Machinery Update March/April) when several of the leading flow-wrapper manufacturers launched software synchronised servo-driven machines, which for medium and high-speed applications have now more or less replaced conventional mechanical machines. We saw a similar step change in 1996 (Machinery Update July/August) when several liquid filler manufacturers simultaneously launched machines using electronic flowmeters. Software synchronised drives The step change in cartoner design that is now evident is the widespread use of independent software synchronised drives in place of the conventional single drive with mechanical power transmission. In most but not all cases these drives are servo motors, so let s call these 100 per cent servo driven machines. Servo motors have been used on cartoners for many years to achieve automatic size changes or to power one or two subsidiary mechanisms, but otherwise these machines were conventionally powered from a single motor. As far as we can make out, the first cartoner to be completely servo driven was an intermittent motion machine, developed by RA Jones for Tambrands and reported by Machinery Update in January The incentive to break away from conventional power Servo drives signal a step change Just as independent servo motors, synchronised by software, have replaced traditional mechanical drives in many types of packaging equipment, so cartoning machinery has followed suit. Report by Martin Keay. transmission methods here was the need to be able to produce a very wide range of carton sizes on the one machine. This technology is now widely available and well established in those packaging machinery applications where the ability to change from size to size rapidly and accurately is an important requirement. However, the unexpected bonus for machine manufacturers in using servo technology has been the realisation that 100 per cent servo powered machines can be cheaper and quicker to build than traditional designs. This has been the experience in the flow-wrapping machine industry where the technology was originally used for high speed and complex applications, but has now become the standard for all applications, high-speed, low-speed, complex or straightforward. Easier to size change RA Jones (now part of IWKA) has followed the lead of the flow-wrapping machine manufacturers to produce a machine which is not only easier to size change, clean and maintain, but is also cheaper than the machines it replaces. Called the Criterion 2000, this new end-load cartoner was first put on show last November at Pack Expo in Chicago. The Criterion 2000 is not just a single design of machine, but a family of machines which can be intermittent or continuous motion, left or right hand and have pitch centres of 3, 6, 9, 12 or 15in to suit a wide range of applications. The different machine variants can be built from a series of standard servo driven modules which are all manufactured from stainless steel. For instance, a single rotary carton opening mechanism is used for all the variants, and with software changes can operate left to right, right to left, with forward or reverse opening cartons, intermittently or continuously with all the flight finger pitch sizes. Reduce the price substantially This modular concept allows us not only to build machines more quickly, but also to reduce the price of the machine quite substantially, explained George Hendry, senior national account manager at RA Jones Inc. Good hygienic design was also a high priority during the development of the Criterion The machine s open construction allows any debris to fall through the machine to the floor and the stainless steel construction makes it possible for all machines to be washed down during cleaning. This facility makes the Criterion 2000 suitable for the frozen food and chilled food industries as well as the other food and pharmaceutical sectors where RA Jones machines are already well established. The reduction in cost has been achieved by replacing complicated mechanical drives with programmable servo drives, and using welded 36

2 frames in place of bolted frames. The Criterion 2000 machines use fewer parts than the machines they replace and so are quicker to build and can be offered on shorter delivery times. The working height of the machine and the design of its guards are the result of ergonomic studies, with the low profile base providing an optimal working height of 812mm and a maximum reach of 610mm. Clear curved, lift-up or gull-wing guards give full access to the machine interior and allow the operator to see all the machine s functions. Bradman-Lake launched its first 100 per cent servo-motor driven cartoners at Pack Expo 2000 as well. The SL9000 horizontal end-load cartoner uses seven servo drive motors, eliminating all the gearboxes, chains and transmission shafts typically associated with large pitch end-load machines. Power the bucket infeed Two servo drive motors power the bucket infeed conveyor, one driving the chain carrying the front walls of the buckets and the other powering the chain carrying the rear walls of the buckets. The front bucket motor is operated automatically during a size change to open or reduce the size of the buckets. During normal operation both drives run at precisely the same speed. Similarly, two servo drive motors power the main flight chains, one driving the chains carrying the front flight fingers and the other the chains carrying the rear flight fingers. Above: Jones Criterion 2000 is built from a series of servo motor driven modules and can be intermittent or continuous motion. Left: Bradman-Lake SL9000 uses seven servo motor drives. Speed is up to 225 cartons a minute One servo drive motor powers the planetary motion carton opening mechanism and one motor powers the barrel loading mechanism which pushes products from the bucket infeed conveyor into the cartons. The final motor operates the flap tucking mechanisms, allowing the timing of the tuckers to be adjusted on the run as well as with the machine stationary. The SL9000 can be supplied as 6, 9, 12 or 15in pitch and features stainless steel construction and gull-wing guards. Speed is up to 225 cartons a minute. Rovema s recently redesigned CMH horizontal end-load cartoner also uses separate servodrives in preference to powering all mechanisms from one central drive motor and has two servo drives to drive the main flight chains. However, the product loading section of the new cartoner is a radical change. Traditionally, cartoners handling products like bags of rice would be equipped with a transfer station linking the bagging machine to the cartoner, a horizontal bucket conveyor to convey the bags in synchronisation to the loading mechanism and in some cases a top confining mechanism to control the bag as it is pushed into the carton. Rovema s new horizontal filling module consists of a cartridge that is open at the top and on the cartoner side. Bags are dropped into the cartridge from above using a servo operated transfer mechanism similar to those used to 37

3 drop bags into a conventional bucket conveyor. Once loaded, the servo-driven cartridge is accelerated towards the open carton and then rapidly decelerated so that the bag slides out of the cartridge and into the carton. The cartridge then returns to collect the next bag. Several filling modules can be fitted to the cartoner to achieve the required production rate and to accommodate the production from more than one bagging machine. The cartridges are made specifically to suit each product and carton size. Four main advantages The new loading system has four main advantages. The first is that it can accept a wider variety of products and product collations than conventional infeed designs. The second is that the machine layout is much more compact. The third advantage is that the new filling system is significantly cheaper, because it is no longer necessary to have a bucket infeed conveyor barrel loading mechanism or top confiner. The fourth advantage is that size changes take less than 10 minutes because only the cartridge needs to be changed. US manufacturer Douglas Machines, represented in the UK by David S Smith, has recently launched a new 400 a minute end-load cartoner which uses servo drive technology. The Douglas model 600S cartoner features independent Allen Bradley servo drives for the carton erection, dust-flap, major flap and compression mechanisms. However, the use of 100 per cent servo motor driven cartoning machines is not confined to end-load models, because the benefits are equally apparent for top-load systems. Indeed, Bradman-Lake s second 100 per cent servo machine launched at Pack Expo 2000 is the LJ-500 robotic product collator and loader. This incorporates advanced electronic motion control technology using nine different servo motor drives. Up to 500 bars a minute The new collator has been specifically designed to handle count-line confectionery bars at speeds up to 500 wrapped products a minute from one infeed point and 600 a minute from two infeed points. The LJ500 can interface with most wrapping machines. A servo driven belt conveyor transports wrapped products into the machine using vacuum to ensure consistent product spacing. Double wrapped or incorrectly spaced bars are separate inverter drives for each section and a servo drive motor powering the right-angle transfer. This method of construction allows the machine to be assembled in a fraction of the time it would take to build a machine with a single drive and conventional power transmission. Rovema s CMV vertical cartoning machine, like the horizontal CMH, is a 100 per cent servo driven model and is of particularly compact dimensions. One or two Rovema VPK or VPI vertical form-fill-seal modules can be integrated into the CMV to form a bag-in-box unit that can be installed in a much smaller space than systems using horizontal end-load cartoning machines. The entire packaging system, including any weighing or filling equipment, can be operated from a single touch-screen operator interface, Modular construction: IWK Cartopac SC4, one of a range that can be readily adapted to future needs rejected prior to the transfer by an air-activated blow-off device. The heart of the collator is what Bradman Lake calls a turbo train conveyor, which consists of two sets of buckets that index at high-speed. Each set is attached to its own belt and is individually driven by its own servo motor. The first turbo train positions the buckets accurately at the junction of the infeed conveyor to receive individual products. When all its buckets are filled, the entire train accelerates forward to a robotic loading station. Meanwhile the second train moves into position and repeats the same operation. Formed cartons are transferred from a carton erecting machine into a positioning conveyor and side belts position the cartons to ensure they are correctly spaced. This spacing is maintained at the point where the robot loads layers of product into the carton which, when filled, is automatically released into the closing machine. First to be developed outside USA Adco Manufacturing has also used independent drive technology for its new RAC-80 right-angle three-flap closing machine. This machine was shown for the first time at the PPMA Show last September and is the first to have been developed and built by Adco outside the USA. Designed in Britain, the RAC-80 is a compact three flap closer with a maximum speed of 80 cartons a minute, but is also available as a single flap closer. Construction is from stainless steel and aluminium and the machine is capable of handling a wide range of carton sizes, with size changing achieved without tools in under five minutes. The design of the RAC-80 is modular with which includes online assistance. The machine can operate in several different modes. Filled bags can be loaded into cartons, the cartons can be filled directly without a bag, or empty bags can be placed in the cartons and be filled afterwards. When the cartons are filled directly, integrated auger filling machines or weighing machines replace the form-fill-seal modules. No complicated transfer system The integration of one or more vertical bag form-fill-seal machines allows direct insertion of the bags into the cartons with no need for complicated bag transfer systems. A new operating principle also makes it possible to insert bags into the open cartons without stopping the carton motion. So, with all this development taking place, what about conventional cartoner design? Will there still be a place for it? Or will all machines 38

4 be servo driven or have independent drives in the future? If the flow-wrapper industry is anything to go by there will continue to be a market for mechanical machines, but not a large one. The greater flexibility, lower maintenance, shorter lead times and lower cost of servo machines have steadily won over customers, including those who were initially put off by the greater sophistication of software synchronised machinery. However, it could be argued that the cartoner market is rather different from the flow-wrapper market and that the issues of handling cartonboard and flexible film cannot be compared directly. We shall see. In the meantime, a look round the rest of the cartoning machinery business shows a fair amount of activity. Designed on modular basis IWK s latest range of end-load cartoning machines for the pharmaceutical and healthcare industries has been designed on a modular basis that allows a variety of optional equipment to be readily included initially, while also taking care of possible future needs for upgrades with retrofits and further add-ons. Indeed, this modular approach also means that the IWK Cartopac machines share a high proportion of common parts over 80 per cent despite being available in a number of versions covering intermittent and continuous motion, as well as 100 or 150mm pitch. Key features of the range, which is built in balcony style for ease of cgmp compliance, include a new rotary carton pick-up and erecting system, fed by a motorised conveyor in place of the conventional gravity hopper. Here the modular approach is immediately apparent, as UK agent Sussex & Berkshire Machinery points out. On the intermittent motion machines, the rotary drum is equipped with just one pick up head to provide speeds up to 120 cartons a minute. But the same drum can carry up to three pick-up heads, allowing the 100mm pitch continuous motion Cartopac SC4 to reach speeds of 450 cartons a minute. The carton erection system employs the overbreak principle to open the cartons more than 90deg and avoid problems with poor quality creasing or internal glue spots, but also incorporates an arm that moves into place to hold the carton square as the transfer is made into the carton chain. Here, to prevent risk of scuffing, IWK has departed from the conventional arrangement in which the carton is carried between flights and supported either end on steel guide rails. Instead, each carton is carried by the chain in a pair of facing L-shaped polymer supports that adjust for pitch in the same way as the flights on a traditional four-chain system. For ease of operation and changeover, the leaflet feeder on the Cartopac is placed to the operator side of the machine, and also includes a new system to improve security and leaflet reconciliation. Once a leaflet is withdrawn and placed in the clip chain that carries it to the loading point, its presence is sensed and compared with the availability of a carton and product. If no product or no carton is signalled, the leaflet is retained in the chain and delivered to a reject box via a counter. Any rejects can then be retrieved and taken into the count to ensure no rogue leaflets remain in the machine. Controls on the Cartopac range are PC based, which allows a Windows style operating system to be employed for operator familiarity and ease of use. However, the PC also carries the machine s operating manual, maintenance manual and parts lists and identification, providing a ready reference source for both operator and maintenance staff. Birds Eye Walls has just taken delivery of its fourteenth C90 carton closer from MY Cartons Packing Systems, formerly Bonar Automation. Size change can be achieved in under three minutes, an important feature because of the different product sizes 170g Cod in Sauce and 375g Curry and Rice which will be run on the same machine. Cartons accepted at random The flightless design of the C90 not only helps to eliminate carton and product damage, but also means cartons can be accepted at random from the packing line. For this machine, Birds Eye Walls has chosen the hot melt jetting version for uncoated board,but the C90 also comes in a hot air sealing version for coated boards. Kliklok s latest machine is the HSR horizontal end-load cartoner which now incorporates a touch screen control panel. This 250 a minute machine has a conventional power transmission system, but uses phasing boxes and quick release change parts to achieve a size change in under five minutes. Two HSR machines were recently supplied to a leading multi-national to pack ready meals. The tray blank... Carton erector to Lerner Burgess has introduced a customised version of its established ECT series of top load carton and tray erectors to produce transit/display trays with apertures to hold bottles, pots, collapsible tubes and the like. It works from flat blanks, allowing the packs to be produced in-house as required and reducing considerably the storage space These machines, which run at 240 packs a minute, were supplied as part of a total line from the Kliklok Group incorporating Lerner Burgess carton collators and shrinkwrappers. Pitch set from the controls In fact, Lerner Burgess has introduced a Mk II version of its C1F carton closer, a servo-driven machine that can tuck or glue close hinged lid cartons with or without dust flaps. It uses polycord belting for transport, with no flights, allowing carton pitch to be set simply from the controls. Speed of the machine is up to 160 cartons a minute. The Marchesini MA horizontal end-load cartoner is particularly suited to the pharmaceutical industry, because it has a cantilever construction that makes it easy to access and clean all the working mechanisms. The product pusher and flap closing mechanism operate in a cyclic motion and the drive assemblies that operate them are housed in completely sealed oil baths. The standard construction for the machine is for size changes to be made using hand wheels and incremental encoders so that size change is fast and repeatable. However, machines can also be supplied with the facility for automatic size changing if required. For small batches, low production rates and short production runs it is often difficult to justify the cost and inflexibility of a fully automatic machine. However the rotary or race-track layout of most vertical cartoners for semi-automatic production is far from ideal when consider- 40

5 ... is first turned and glued at the side and then completed with top flaps glued make transit/display trays as well required for pre-erected trays. The new model 625 SC operates with either cartonboard or corrugated blanks, first producing what is in effect a shallow top load carton with the sidewalls glued but with two major flaps as unglued half-width lids. The carton is ejected onto a flighted conveyor and taken through guides where the major flaps are ploughed down into position. The carton is then transferred 90deg through a series of guides and the minor flaps glued and turned down. As well as these transit/display trays, the Lerner Burgess 625 SC can also erect conventional top load cartons and trays. More information - enter 161 ing ergonomics and a logical work flow. The answer from Stamford Packaging is the Isopac Delta 3 cartoner, a 60-a-minute machine built in a triangular configuration. This enables packs to be handled in a straight line, but in a very small footprint of less than 1.5 metres square, while the machine itself can be readily relocated using a pallet truck. The balcony construction loading area, with room for up to three operators, coupled to a carton transport system using belts rather than conventional chains, means that the Delta 3 runs quietly and is easy to clean. It was specifically designed for the pharmaceutical and cosmetics industries, so all its mechanical drives are enclosed within the base. TMG Marchesini s vertical intermittent motion cartoner, called the Polycarton 900, can be fed either manually or automatically. It cycles at up to 90 cartons a minute with the size range extending from 15 x 15 x 50mm to 120 x 90 x 250mm. Compact vertical cartoners Meanwhile, German manufacturer U-E-T has been finding that the market for compact vertical cartoners is not confined to manually fed applications. In one recent installation in the confectionery industry, U-E-T s compact cartoner was installed with a multihead weigher dispensing wrapped sweets. The labyrinth folded flaps of the carton were sealed using hot-melt adhesive. UK agent Soudal says that a major advantage of U-E-T s range of machines is their particularly small foot print of 1.5 x 1.5 metres, which makes it easy to fit them into a crowded factory layout. Both intermittent and continuous motion cartoners giving speeds up to 120 a minute are included in the end-load range built by Almatec, Holland, and now available from Propack Automation. Some models employ a walking beam, box-motion style carton transport, which Propack points out is particularly well suited to large panel cartons in lighter board qualities. Almatec also produces top load machines, as well as vertical machines giving speeds up to 90 a minute for free-flowing products. FOR FURTHER INFORMATION: Adco Manufacturing enter 147 Bradman-Lake enter 148 RA Jones Europak enter 149 Kliklok enter 150 Lerner Burgess enter 151 TMG Marchesini enter 152 MY Cartons Packing Systems enter 153 Propack Automation enter 154 Rovema enter 155 David S Smith Packaging Systems enter 156 Soudal enter 157 Stamford Packaging enter 158 Sussex & Berkshire Machinery enter 159 For full details of all PPMA members able to supply cartoning equipment, enter 402 on the free reader service card in this issue, or visit the PPMA web site: 41