Spicing up automation!

When PCE Automation was challenged with designing a new handling system for automating the manufacture of a brand new concept of spice jar lid by plastics manufacturer RPC Halstead, it turned to Festo.

“Festo brings variety to the spice of life”

The ‘Spoonkler’ lid manufactured by RPC Halstead, for its end customer Bart Ingredients, is an innovative flip-top cap that can be opened in two ways, either to reveal a collection of small holes through which the spice can be sprinkled, or a full opening wide enough to fit a teaspoon. For this demanding project RPC invested in special manufacturing equipment from PCE Automation. The new cap presented some unique handling challenges requiring an innovative mechanism designed by PCE with support from the Festo application engineering team.

“A particular challenge of the design is the cap’s opposing side hinges, which enables it to be opened in either spoon or sprinkle mode,” says Julian Tarratt, sales manager at PCE Automation. “We have used Festo equipment in our machines for a number of years and we are always pleased with the wide range, high quality and reliability, which are vital to us being confident in delivering high performance machines to our customers. So naturally, for this project, we turned to Festo again, but even with the range we needed to do something special.”

In addition to the unique hinges, there were a number of additional challenges and constraints. First, the robot had to be designed with a small footprint so it could fit easily next to the plastic injection moulding machine.

Second, to remove the tooling from the plastic moulding machine, a crane needed to fit between the machine and the robot. The robot arm that collects the moulded caps therefore needed to be completely retractable from the moulding machine, to allow the crane access when required.

Finally, the machine required more operations than are typically used in alternative cap moulding applications in order to close the caps’ two opposing hinges, which need to be shut directly after moulding.

PCE Automation designed a side entry robot that uses a Festo high speed electric axis and pneumatics. However, as the electric axis needed to be fully retractable, PCE Automation adapted one of the electro-mechanical belt drive axis and designed a bespoke solution. The company’s specialists came up with an ingenious method of piggy-backing two linear electric axes together, to form a telescopic arm that could be fully withdrawn from the injection moulding machine, therefore enabling the crane easy entry.

“We are delighted to have worked with PCE Automation on the project,” says Allan Price, Business Development Consultant at Festo. “Prior to PCE manufacturing the handling arm, we worked closely with their design team, discussing their requirements and advising whether it was feasible, and would deliver the high quality results the company was looking for. We’re very pleased it does!”

In the process 12 caps are injection moulded in black polypropylene. The Cartesian robot arm enters the moulding machine to remove the un-folded caps and once returned to the automated machine, the first hinge is folded shut. The machine then uses Festo pneumatics to accurately and reliably move the caps to the next process, where the second hinge is folded, before being transferred to the conveyor at the end of the assembly line.

“We have applied the extensive automation experience we have amassed over the years to design this new automation handling solution,” said Julian. “The Festo products provided an ideal platform for us to build upon and the fact the parts were readily available within a few days meant we could pull the design together and build and deliver our machines more quickly.”

“This has been a real team effort with PCE Automation and Festo both rising to the challenge,” says Andy Edwards, Engineering & Technical Manager at RPC Halstead. “We are delighted with the performance of the new robot and since installing it, we have been able to manufacture the lids for the spice jars reliably, while operating efficiently, and most importantly, our end customer Bart Ingredients is also pleased with the results, as the Spoonkler cap delivers market-leading functionality, allowing consumers the choice of spooning or sprinkling.”