Packaging by Piece Count with a Yamato Combination Scale: It Always Adds Up

Written by Jake Hilbrandt, OEM Accounts Manager

Many products consumed in our daily lives are sold by a specific piece count. For example, packaged chicken, muffins, and gummies are often marketed with a specific number of pieces in a package – and consumers expect to see that exact amount inside. Inaccurate counts not only affect customer base and future buying habits, but inaccurate counts also negatively impact the bottom line. With supply chain and raw material issues at an all-time high, it is paramount for packaging conglomerates and local small businesses alike to reduce giveaways and improve their efficiencies. Luckily, a Yamato combination scale is not only an industry leader in accuracy by weight, but accuracy by piece count as well.

Yamato’s Process for Packaging by Piece Count

Every Yamato combination scale comes with the capability to include “counting software,” or rather, a software that counts and dumps products by their individual weight. If a customer would like Yamato to guarantee a specific piece count, we request that a minimum of 100 samples be sent to our office in Grafton, Wisconsin, in the same condition it would be introduced to the scale. Once received, each piece will be weighed individually and documented in a spreadsheet. From there, key data points will be determined. Key numbers we are looking for and calculating include the average weight of one individual piece of product, and the standard deviation of every piece compared to the average.

  • Items with Low Standard Deviation/Uniform Products: Products like vitamin gummies and pills, confectionery items such as chocolate bars and bite-size candies, electrical components, and laundry pods are advantageous for counting. Items with correlating, consistent piece weights result in the scale precisely computing how many pieces are in each bucket, and eventual combination.
  • Items with High Deviation/Variable Products: Products with more inconsistent weights like many IQF foods and meats, vegetables, and other grown or organic products often present problems for the scale to identify how many pieces are in each bucket. This may result in counting inaccuracy and giveaway.

Upon finding the average weight and standard deviation of the individual product pieces, Yamato Corporation is then able to make calculations such as the range of pieces we would like in each weigh bucket for ideal combinational accuracy, as well as the number of pieces to which we can accurately count with combination scales.

Benefits of Counting on a Scale

The benefits of using a Yamato combination scale to package by piece count include:

  • Reduction in Giveaway: When counting software is in use, the scale will simultaneously set six parameters: target count, a high limit of pieces, a low limit of pieces as well as incorporating overall weight in the form of target weight, a high limit of weight, and a low limit of weight. This is done to ensure that not only is the most accurate count computed and dumped by the scale, but also the most accurate weight is dumped, which increases efficiency of the packaging process.
  • Adaptability: Counting software tracks average piece weight trends and makes internal calculations to optimize the performance of the scale. This is incredibly useful for bakery applications, for example. During the packaging process, when ovens first begin warming up, product is often left slightly undercooked. This results in pieces of product that flake off or break during transfer to the scale. Once the oven becomes fully warm and the products become consistently cooked, there will be less breakage and, as a result, the pieces will weigh a little more. A Yamato package-by-piece combination scale using counting software will be able to track and monitor these trends and adjust accordingly.
  • Counting and Weighing Versatility: While counting products with photo eyes and other means certainly have precedence in niche markets, these machines tend to be designed for one specific product and a narrow range of counts. A key advantage of Yamato scales is that a broad range of products can be counted, and product count can range from 1 to hundreds of pieces per each target package. These different product types and target counts can easily be programmed into individual recipes on the scale’s HMI, saving time and eliminating the chance of operator error through manual adjustment.
  • Reject Capability: A negative to running low counts on combination weighers can be poor feed that can lead to overweight buckets. For a standard combination weigher, this could result in the need for a rejection bucket between the scale and the filler. This option works, however, it is very costly due to performance loss. If the scale needs to reject 1 out of every 10 cycles due to over weights, the packaging line will only be running at 90% efficiency. Manually removing overweight buckets is another option, but this results in needing an operator to monitor overweight buckets and creates more of a semi-automated packaging line. Yamato uses patented reject technology called SVR to make our scales the most accurate and efficient counting scales in the world. Yamato offers several efficient reject solutions to help you maintain the highest possible number of combinations for your multihead weigher.
Test it Out: Counting Cannabis

Cannabis-infused gummies and other cannabis products represent an exponentially growing market – a market where supreme accuracy is crucial. To adjust to this market growth, Yamato has created a pioneering machine – the Omega Frontier Series O-0114F scale. Frontier technology is patented by Yamato and features two unique product paths within the collating funnel of the scale – an inside and an outside chute.

For this Omega Frontier scale, we assigned a challenging task – counting 1 three-gram CBD gummy at speeds of 80 weighments per minute (wpm). We programmed the two-way weigh bucket, standard on the O-0114F, to dump overweights – in this case more than one gummy – down the outside chute, while good weights – one gummy – were sent down the inside chute. Here is a quick overview of advantages to having two product paths on one machine:

  1. The bag-making machine will be unaffected by rejected product, creating a consistent and efficient feed from the discharge of the scale. Interrupted and start-stop operation derived from waiting for a reject to clear the transition funnel can create timing, sealing, and signaling problems, all of which are avoided with totally separate product paths.
  2. Accurate combinations and speeds are maintained, as overweight buckets can be quickly disposed of and refilled to bolster the quantity of possible combinations.

Utilizing this technology, the scale was able to achieve a 1 count at 80 wpm over 1500 times in a row!

Want to switch to a high-speed simplex application or a duplex format that is calculated purely by weight? Not a problem. Just adjust the collection buckets underneath the scale, switch to these respective modes, and you will have a 150wpm simplex machine running 12-gram target weights, or a duplex running 50wpm on both discharge points.

The Yamato SVR for Counting

The Yamato SVR is another patented Yamato technology and operates similarly to the Omega Frontier O-0114F. Weigh buckets on this machine are also outfitted with dual-acting doors, with accurate combinational weights being dumped down the collating funnel. Overweights, on the other hand, are dumped to the outside of the scale. Rejected product is deposited onto an attached rotating ring, which offers the unique advantage of re-introducing product at the mezzanine level, as opposed to the operator level down below. Rejected product can then be inserted back into the feed system. This layout offers a more limited footprint and eliminates the need for additional conveyors or elevators, saving both space and the cost associated with purchasing and operating a large conveying system.

Important Items to Remember When Counting on a Yamato Scale

When using a multihead weigher to package by piece count, there are two things to keep in mind:

  • Proper Infeed: While having reject capabilities provide a fantastic tool to ensure the highest number of combinations possible, the root cause of overfilled buckets is often improper feed to the top of the scale. Yamato has found that using a vibratory crossfeeder is the best way to achieve consistent feeding on to the scale’s top cone to ensure product is evenly dispersed into the linear feed pans and, after the feed buckets, the weigh buckets.
  • Changes in Product: While a Yamato combination scale can adjust for average piece weight over time, for counting purposes, it is beneficial to keep product as uniform as possible. We ask that samples be sent to our Yamato office in Grafton, Wisconsin, in the same exact condition as if they were about to be introduced to the multihead weigher.
Counting with a Yamato Scale: It Always Adds Up

Counting on a Yamato combination scale presents unique opportunities and advantages by giving packagers versatility and accuracy, no matter the application. Meeting customer expectations and doing so in an efficient manner will always be an industry standard, and here at Yamato Corporation, we strive to provide relevant solutions to everyone’s weighing needs.

Are you interested in knowing if your product could be accurately counted on a scale?

Do you have an existing scale you’d like counting software added to?

Contact us for more information on packaging by piece count. We’re here to help. (You can count on us!)