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VarioFlow plus system allows modern production of tea bags

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March 2017

 

Thanks to a quick and compact conveyor system, the tea company Yamamotoyama can run multiple tea bag flavors simultaneously and quickly within a confined space – and without damaging the product.

The family owned and operated Tea Company Yamamotoyama was founded in Tokyo in 1690. The founder Kahei Yamamoto II had a dream of introducing green tea, which at that time was only accessible to the wealthy, not to the general public. He learned that steaming the tea leaves instead of brewing them, which was the accepted method at that time, resulted in a more delicious, sweet tasting tea that retained its nutrients. The tea was an instant sensation, making Yamamotoyama a household name. Since that time the company has expanded its operations around the globe while staying current with modern manufacturing methods.

Yamamotoyama of America was seeking to improve its production operations in Pomona, California, in order to achieve greater productivity and flexibility in producing multiple products. The facility operates multiple IMA tea bag manufacturing and carton machines, each of which can produce 300 tea bags, which is 18 full cartons of tea bags per minute. Once cartons are produced, the next step in the process is packing the full tea cartons into shipper cases, then labeling the cases and palletizing for shipment. As management at Yamamotoyama planned to expand production, they needed to add more automated case packers, which in turn needed to be sourced from the tea cartoning machines. A carton delivery conveyor system from the tea cartoners to the case packers was needed, with the ability to organize multiple flavors to the case packers in the proper grouping of 12 cartons per flavor.

Flexible conveyor system

In search of a fitting conveyor system, the management at Yamamotoyama contacted Bosch Rexroth with an inquiry about the VarioFlow plus system. This flexible, modular plastic chain conveyor system is used for moving high volume packaged goods and other consumer goods. It can be used to move products horizontally, vertically, on incline or decline, overhead, sub-floor, around obstacles and over long distances. Yamamotoyama was interested in VarioFlow plus because of its smooth running belt, low profile channel, tight radius curve wheel and ability to create a ‘stacked’ conveyor configuration with vertical curves. Daniel Goldstein, COO of Yamamotoyama of America, explains: “We needed the flexibility to source multiple flavors of tea product from multiple IMA cartoners into a single IMA case packer. We researched Rexroth products, and selected Bosch Rexroth Corporation due to their quality products.” Each IMA machine can produce just one flavor of tea at any given time, however the Yamamotoyama plant is arranged in a way that the machines are located in groups, each producing 18 cartons per minute. This meant that the conveyor system had to accommodate this volume of tea cartons per minute, and accurately merge groups of 12 cartons into the case packer, without error. A second requirement was to protect the carton surface. The tea is packaged in glossy, shelf ready cartons, and the appearance of the carton needed to remain neat and unscratched. Therefore, a smooth surface conveyor belt would be required. The third challenge was one of space. The plant equipment spacing is very compact, with minimal lateral distance between production equipment, so the conveyor system needed a very small footprint.

Inclines and declines as well as lateral offsets at the Yamamotoyama facility made it possible to minimize the floor area. Magnifier

Inclines and declines as well as lateral offsets at the Yamamotoyama facility made it possible to minimize the floor area.

 

Stacking for a narrow footprint

TransAutomation Technologies Inc., based in Santa Ana, California, and a member of the Bosch Rexroth ProBuilder network, was asked to complete the design and build of the system. According to Mr. Goldstein, “We needed the system to be locally supported, and were confident in the fact that the system would be built and completely integrated by the local ProBuilder, TransAutomation Technologies.” The mechanical design of the VarioFlow plus conveyor needed to be complemented with custom mechanical devices for controlling product groups of cartons, and further integrated with an electronic controls system. Yamamotoyama system receives the output of the IMA cartoners onto individual take-away conveyor runs. The Rexroth conveyor elevations were varied through the use of vertical inclines and lateral off-sets to achieve a stacked configuration, allowing for a very narrow footprint. At the terminus of the system, the product travels in a vertical incline onto the trunk conveyor through the use of vertical curve declines.

Count to 12

Once product cartons approach the end of the Rexroth conveyors prior to the case packer, they stop and accumulate at the end of each of the conveyors. An electronic controls system counts the cartons in queue, and via a priority counting system, the control PLC establishes which conveyor lane is to be released onto the trunk line. Once 12 cartons are accumulated on any given conveyor, that conveyor is ‘eligible’ to release the slug of 12 cartons onto the trunk line. The slug release is accomplished through the use of pneumatic stops, escapements and right-angle pushers. The shortest conveyor line with the least amount of accumulation capacity has the highest priority, then the second, and so on.

As a conveyor is signaled to release product, a custom right angle pusher activates and ejects the cartons, six at a time onto the trunk line. Two pusher activations are required to create a slug of 12 cartons, as required for the case packer. All conveyor sections in the accumulation area are constantly monitored by the electronic controls system to keep the cycle repeating throughout the production run. Once tea cartons enter the capacker in groups of 12, two full shipper cases of six cartons each are produced and discharged from the case packer. Cartons are printed and then rotated upright, to be palletized by the robotic palletizer.

Since the shelf-ready cartons must not be scratched, Yamamotoyama uses a conveyor belt with a smooth chain surface. Magnifier

Since the shelf-ready cartons must not be scratched, Yamamotoyama uses a conveyor belt with a smooth chain surface.

 

A huge success

The solution increases the speed of production without damage to the products, all in a small footprint. “The project went very well from start to completion,” states Goldstein.