Automatic screw feeder drivers are, by design, easy to use. For operators, the screw feeder (also known as a screw presenter or screw dispenser) replaces an open bin or shaker tree as their screw supply. They simply touch the tip of their tool to the screw presented by the presenter, turn, then fasten it into the appropriate area. Operators never have to fumble for their screw, which significantly increases their throughput. Entirely automated systems using screw feeders are in some ways even simpler. Instead of an operator, a robotic arm takes the screw presented by the screw dispenser, turns, and fastens it. The purpose of these systems is to simplify the screw supply process for operators or robotic assembly, and they do their job well.
The question of how to use an automatic screw presenter, then, comes less often from the operator on the line than it does from the systems designer or engineer. The operator likely already knows how to use the machine, but it’s up to the systems designer or engineer to decide how, where, and when to employ each automatic screw feeder. This can be a larger challenge. After all, it’s important to get as much out of your investment as possible. Here are some of the top ways designers and engineers can employ automatic screw feeder drivers to maximize success.
Know Your Product
The first question to ask when considering installing screw presenter machines in your assembly process is, “will these be materially helpful when assembling my product?” It may seem like an obvious question, but for some products, screw feeders won’t necessarily improve assembly in a significant way.
For instance, screw dispensers are best at presenting large numbers of the same screw—two per second—to a fixed point. If your product only takes four screws, all of different sizes, you would need four screw presenter machines, and you likely wouldn’t greatly increase your assembly speed.
On the other hand, if your product requires forty of the same screws, all in a line, and the slowest part of the operation is the seconds it takes your operator to find each screw in their shaker tray, a single screw feeder machine can significantly increase your throughput. The total benefit of a screw presenter can be found by multiplying the time savings per screw by the number of screws (Benefit = time savings/screw x number of screws). If the savings you expect to generate cover the investment cost of the screw dispenser in a reasonable amount of time, then an automatic screw feeder driver is a good choice for your company.
Position Screw Feeders for Maximum Benefit
Not only do you need to ensure your screw feeder is being used on the right product, but you also need to be certain is it employed at the right position in your assembly process. To find the correct location for your screw presenter, consider a few factors:
- It must integrate into the assembly flow with minimal disruption.
- It must be easily and ergonomically reachable by your operator.
- It must be easy to refill and maintain.
Whether you’re manufacturing in a line, cell, or combination process, it’s important to place your screw presenter, and therefore your operator’s workstation, in the right location. Generally, it’s best to position your workstation at the nearest point to the product’s next and last assembly station so it can flow through the line in the shortest amount of time. Any gains the screw feeder provides in operator efficiency can be offset by losses in overall assembly flow efficiency, so it’s important to locate your screw feeder directly.
At the same time, it’s a good idea to design your screw dispenser system so that refilling it will be simple. Screw presenters can be fed in two ways; locally from an input bin or via piping from a central location. Local screw feeders have large input bins, reducing the need for constant refills. However, if these machines are in difficult to reach locations, refilling them may be an onerous process which could potentially cause delays. To combat this, screw feeder systems which carry screws from a central location to their presentation point can be installed. However, these custom systems will likely have higher price tags. In addition, their maintenance and repair can be complicated and may require technicians to navigate tight spaces in the walls or behind the machinery. The screw dispenser system would be obliged to go offline while technicians are working on it, causing downtime across the assembly process. If possible, it’s ideal to keep ease of access in mind when designing the placement of your screw presenter system.
Finally, if you’re employing human assembly workers, it’s important to position your screw presenter with an eye for ergonomics. Repetitive motion injuries are exacerbated by awkward assembly positions and can lead to worker downtime and medical costs. To reduce repetitive motion injuries, position your screw feeder machine in a location which minimizes the amount of strain on your employee’s joints and backs when picking up a screw, turning, and fastening the screw.
Automatic screw presenters can dramatically increase your assembly speed, helping your process move almost 50% faster than it would if you used open bins or shaker trays. However, in order to realize these gains in efficiency, it’s essential to take care when designing your screw supply process. Getting the best use out of your investment in an automatic screw dispenser depends on the machine’s application and location. For advice on how to get the most from your automatic screw feeder driver, ask one of our representatives to take a look at your assembly process.