A confectionary company required a special purpose labelling machine to apply security labels to all four sides of a box of sweets and to accommodate a range of pack sizes.
York-based, Sessions Label Solutions likes a challenge. It is a company that takes on labelling projects that most of its competitors reject. However, thanks to its considerable design and applications know-how Sessions is immensely successful at what it does. For this reason the company was the obvious choice for a special purpose labelling machine for a confectionary company of international renown.
A single machine was required to apply security labels to all four sides of a box of sweets and also to accommodate a range of pack sizes. And that meant designing a system whose labelling heads and parallel conveyors could be moved in unison to pre-determined positions to accord with box dimensions. Having used HepcoMotion linear motion products for many years, Sessions once again put its trust in this brand for this application too.
The basis of the resulting system is two pairs of parallel conveyors mounted on linear slides that are coupled together to form an ‘L’ shape. These parallel conveyors on each leg of the handling system provide the means to adjust the width to suit the different box sizes. For the maximum box width of 400mm the conveyors are at their widest apart and for the smallest, 100mm, they are brought together and almost touching.
This has to be precisely accomplished as the customer requires L-clip labels to be applied. To achieve this, the box has to overhang the 30mm wide conveyors on two opposing sides, so that label can be affixed to the side and bottom faces of the box. The linear speed of the conveyors is 30m/per minute with a maximum product throughput of 60 boxes per minute.
To move the conveyors in and out, Sessions chose the double-acting PSD80. This linear actuator is perfectly suited for this duty, with drive from a stainless steel lead-screw operating with a bearing polymer nut. It employs Herculane ultra-high performance wheels mounted in an adjustable carriage body for zero play linear motion. The double-acting version of this unit proved ideal for Sessions as it allows the adjustment of both conveyors from the operator side.
“The ability of the PSD80 to run dry was an important factor in our choice,” explained Sessions Sales Director, Gary Hall. “So too was its neat design, especially the enclosed screw on the linear adjustment.” Indeed one of the most popular features of this product is its stainless steel cover that effectively seals the unit from debris. It is therefore a natural choice for many food handling applications that require a space-saving and hygienic drive.
The labelling heads of this special purpose machine are fixed to the carriage plates of the GV3 linear motion system that easily provides the required positioning accuracy of ± 1mm. The entire machine is mounted on the MCS aluminium machine construction system. “We like this product because it looks smart, it’s easy to build and versatile to accommodate changes,” Gary Hall adds. “Quick delivery and good price are important factors too.”
In operation, the conveyors and label heads on both sections of the machine are manually adjusted to suit the dimensions of the next batch. On leaving the packaging line, the boxes then travel down the first pair of conveyors to the label heads where the L-clip labels are applied to the first two opposing sides of the box and secured underneath. They are then turned through 90° by the cross over unit and steered along the second pair of conveyors for the application of L-clip to the two remaining faces.
Gary Hall concludes, “The system and the HepcoMotion products are working very well. We have successfully fitted HepcoMotion to many of our systems over the years and have always found them to be good value and good quality products.” Both are very important factors in an industry where cost- and production efficiency are vital ingredients.