New KHS palletizing concept for the beverage, food and non-food industries

Hans-Werner Holzer*

With the Innopal PB1NF KHS is giving the beverage, food and non-food industries a new, gantry-style palletizing system which compared to the classic Innopal PB1N setup performs at a much higher speed. Where the Innopal PB1N manages up to 380 layers per hour, the new single-station palletizer with level compensation – and also a low-level pack feed – can process 500 layers maximum in the same time. With this the palletizer achieves processing speeds which are usually only possible with a high pack feed, yet has all the advantages of a low-level product feed palletizer. 

Predestined for non-returnables yet also utilizable for returnables

The Innopal PB1NF is equally suitable for use in the beverage industry and in the food and non-food sectors. Its prime task is to palletize non-returnable packs. The Innopal PB1NF can cope with layer weights of up to 200 kg; the block height including the pallet may be a maximum of two meters and pallets can be up to 1.3 x 1.3 m in size. Whether you want your cans, plastic containers or glass bottles packed in film, cartons or trays, it's all doable. As the palletizer operates with a pusher plate returnable packs can also be processed if required (such as high and low-wall plastic crates), giving operators maximum flexibility. 

Low maintenance and low wear

As opposed to high-speed palletizers with a roller gripper head another major advantage of the pusher plate machine is that there are fewer moving parts, therefore the maintenance requirements and amount of wear are reduced. As a rule, on KHS palletizing machines what are known as pusher plate constructions have a 3D surface structure. This means that thanks to a slight rib on the surface no vacuum is formed when packs are pushed over onto the plate 

*Product Management, Palletizing Technology, KHS GmbH, Worms, Germany.
Phone: +49 6247 973351

and film packs, for example, are in no danger of becoming stuck by suction. This ensures that all types of pack are palletized extremely gently. 

Investment costs reduced and ease of operation improved

With its high performance of up to 500 layers per hour, the Innopal PB1NF is a novelty among palletizers with a low-level pack feed. In fact, low infeeds have many benefits over palletizers with a high-level pack feed. For example, there's no need for a platform which both helps to cut down on investment costs and improve the ease of operation. There's also no need for the packs to be processed to be conveyed up to a given height. Companies don't have to invest in inclined or spiral conveyors, again lowering costs and also reducing the amount of space required for the system.

Major deficit in performance on low infeed palletizing equipment now eliminated

One of the classic deficits of palletizers with a low-level pack feed is that the formed layers have to be conveyed up from the feed area to the level of the waiting pallet block. This makes conveying segments longer than they would be on a high feed palletizer as a palletizing lift is used which has to be lowered back down by a certain distance after each layer has been positioned. In comparison, this means that on palletizers with level compensation the performance is reduced. 

The fact that the cross conveyor usually has to be raised after placing the last layer onto the pallet curbs the palletizing speed on machines with a low-level pack feed even more.  Once in place, the cross conveyor then has to wait until the finished pallet has been discharged from the system. Only then can the cross conveyor travel back down to the level of the table and the next layer be pushed onto the pusher plate by the grouping station. 

This wait is a thing of the past on the Innopal PB1NF. Here, at the front end the cross conveyor no longer has an integrated bar construction but a barrier which automatically opens as soon as a pallet load is finished and ready for discharge. This allows the cross conveyor to travel down to table level and pick up a new layer while the pallet is being changed. This method of operation greatly increases the palletizing speed compared to the previous machinery. 

KHS inline robot grouping for maximum flexibility

When it comes to an ideal palletizing process there are two aspects which are very important: layer formation and the grouping station. The Innopal PB1NF can work with standard grouping systems and also with the KHS inline robot grouping. At high speeds and with a great number of different formations the latter robot grouping system is recommended. Here, two four-axis Innopal RK4 robots normally prepare the layers. This system earns further acclaim as pack manipulation elements, such as turning stations, are no longer required, thus considerably shortening the pack feed segment. In addition to the resulting cost benefits, this has the additional major advantage of gentle pack handling. At the same time changeovers to new pack formations can be very fast where the inline robot grouping is utilized. 

Precise, extremely gentle pack positioning 

Innopal RK4 robots have positive-fit grippers which can pick up one or more packs simultaneously. The robot heads can be adjusted fully automatically by a servo motor within a range of 120 to 400 mm. What's important to note here is that the clamped packs are turned and moved with millimeter accuracy. The packs are positioned with the utmost precision and extremely gently in movements which perfectly match the speed of the plastic chain mats. In addition, the robot gripper elements are plastic coated as a standard and therefore meet the requirements of even the most sensitive of packs. 

Perfect layer formations and high overall stability of the pallet load

Positioned in full keeping with the given specifications the packs travel towards a limit stop at reduced speed where the formation is automatically centered from all sides. This enables perfect layers to be formed and ensures a high overall stability of the pallet load. A pusher then pushes the formed layer onto the awaiting plate and the cross conveyor takes it up to palletizing height. The layer is discharged onto the pallet gently and with perfect precision from a low height onto the ready-formed block or – in the case of the first layer – straight onto the pallet. Layers can be centered above and below the pusher plate. The grouping station can then be returned to and another layer retrieved. 

Various pallet conveying options

Empty pallets are always conveyed on a separate pallet conveyor below the grouping table to the Innopal PB1NF, thus saving space, prior to which they are checked. The classic feed-through inspection system can be used here, where a roller travels over and tests each pallet board. Another option would be to use load testing which verifies the pallet's load capacity. Yet another option is to see if the pallet height, length, width and blocks conform to specifications. This inspection is usually carried out by light barriers. If required, the pallets can be cleaned by rotating or stationary brushes before they pass through inspection. A roller can also be fitted above the conveyor which can push any nails protruding from the pallet back into the wood. There are also many other peripheral options available for the pallet infeed area which include pallet conveying segments with integrated pallet magazines, pallet shuttle cars, turning segments and corner turntables. 

Optional, fully automatic pallet lining system

In order to ensure even less operator involvement and permanently maintain  palletizing performance a fully automatic pallet lining system can be included as an option. To this end, two pallet conveyor systems are arranged as a double deck. On the top deck are several pallets with pallet liners – this geared entirely to the requirements of the company – with the one entering the magazine being processed. Here, the pallet liners are centered on all four sides so that they are precisely positioned. A handling robot grips the pallet liners needed for the palletizing job using a vacuum suction device and places these on the product pallet. Once the pallet in the magazine has been processed, it is lowered to the bottom conveying level and discharged from the system. A new pallet of pallet liners then enters the magazine automatically and the process continues without interruption.  

PC control for improved communication

One of the core components in the KHS palletizing system is the utilization of identical control concepts. Both the inline robot grouping and the Innopal PB1NF therefore have a PC as their control computer which is placed in a modular, plug-in system control cabinet. This eliminates any possible problems with interfaces right from the start. PC-based control also allows quick adaptation to new, product-dependent travel distances. Simple entry on the operator panel is enough to set the system up for a new format. Another big plus of PC control is that it is compatible with the standard bus systems used the world over, ensuring that the palletizing area can readily communicate with the other components on the line. 

Direct online help available on request

Another aspect which promotes system availability is the integration of ReDiS (Remote Diagnostic Service) into the concept. If problems arise, the client is directly connected to the KHS ReDiS service center where an immediate remote analysis is carried out. In the best-case scenario the machine problem is solved by accessing the electronic system components online. If mechanical components are involved, the engineer on site is told precisely which actions to take. If required, ReDiS also permits online transmission of new programs from KHS headquarters and generally helps to ensure the high availability of the customer's palletizing equipment.

Virtual viewing of new palletizing equipment prior to purchase

When a company in the beverage, food or non-food sector is planning to invest in a new palletizing concept, the planned system can first be viewed virtually at KHS before that company decides to invest. For example, the Innopal PB1NF with an upstream inline robot grouping and any required options can be studied in 3D and in full detail either on a PC or on what's known as a Powerwall. The advantage here is that should one or other component prove less convincing than originally thought – when seen virtually – this can be recognized in good time and appropriate countermeasures taken. 

3D planning also helps companies to see how their customized palletizing system connects up with machines before and after it on the line. This makes any interfaces immediately visible, enabling them to be properly assessed and, if necessary, varied, resulting in a truly holistic planning process. 

Numerous advantages

To sum up, the Innopal PB1NF with its low-level pack feed is an excellent alternative to palletizers with a high infeed, outputting up to 500 layers per hour. Thanks to the fact that the cross conveyor is open at the front end, compared to classic palletizing concepts with level compensation performance can be boosted by up to 40%. As opposed to high-performance palletizers with a high-level pack feed there are also plenty of investment benefits, as neither spiral nor inclined conveyors at the infeed nor an operator platform are required. And, last but not least, the newly developed palletizing concept provides companies with far greater ease of operation.