It’s no surprise that home appliances are growing increasingly feature-rich. But underlying this new age of functionality is a dense network of electronic systems and components – many of which are still assembled by hand. Worker safety is at risk, so we're closely collaborating with our customers to put assemblers at the forefront of thought around connector design. 

Customer Challenges

• Growing IoT features, more streamlined designs and other functionalities of home appliances are resulting in more dense, complex electronic systems.
• Appliance assembly staff are now exposed to higher risk of injuries, such as carpal tunnel syndrome and muscle damage, caused by repetition and strain.

Molex Solution

• By closely collaborating with home appliance manufacturers and their assembly teams, Molex designs connector features to ease assembly.
• Connectors are software-tested to ensure they fall within safe mating force ranges and incorporate best practices for ergonomic design.

Carpal tunnel syndrome (CTS) affects an estimated 5% of adults in the United States, with similar numbers seen elsewhere. According to Johns Hopkins, two of the most common causes of CTS are frequent, repetitive small movements and grasping movements: both highly common with assembly line workers, especially around mating connections. With major appliances now incorporating up to 15 signal connectors and 4 to 6 power connectors on the various electronics’ printed circuit boards (PCBs), we have a societal responsibility to protect those in the factory and on the assembly line. 

Through innovation, engineering expertise and close collaboration with home appliance manufacturers, the teams at Molex identify off-the-shelf and custom solutions that make assembly safer, more comfortable and more enjoyable for workers. 

Here are some ways we protect worker safety.

1. Reducing Mating Force: Molex designs low mating force contacts and also uses software to ensure that operators can comfortably mate connections without overexertion, easing the strain of repetition. Less strain means less risk of injury. 
2. Considering Housing Design and Lead-in: By pre-aligning housings and supporting the lead-in, operators can more quickly and easily mate contacts. A bonus — eliminating rework not only reduces repetition, but also removes a source of worker frustration, leading to a happier and healthier team. 
3. Smoothing Push Points: By rounding connector corners, the area in which the operator pushes together the connection is free of sharp edges and dangerous pressure points. This reduces injuries caused from cuts and punctures while also making a more comfortable assembly. 
4. Incorporating Audible and Tactile Feedback: Through audible and tactile feedback, operators can hear or feel when the connection has been made, reducing unnecessary strain and second-guessing, another source of worker frustration.

Delivering a superior customer experience requires more than just designing for performance, quality and reliability. Mating force — a measure of how much pressure is necessary to mate connectors — may not be at the top of the list of considerations for many design engineers, but it significantly influences assembler comfort and safety. A typical connector target mating force is between 5.5 and 7 lbs. of pressure but requirements can differ per appliance manufacturer. Molex incorporates a variety of design techniques to reduce the physical pain and discomfort associated with repetitive mating.

It isn’t enough to just design for reduced mating force, we prove it through data-driven testing, providing added assurance to assembly operators. We use specialized software — HandPak — to test the pressure required to mate a connector and to ensure the pressure falls within safe mating force ranges. The software also compares the level of ergonomic improvement achieved by the new connector solution to a previous design, providing an important measure for worker health and safety. 

Health goes beyond physical wellbeing, and protecting the employees of our customers requires more than preventing injury. A recent study of the cognitive health of assembly workers found several leading stressors, including time pressure and precision work — both applicable to an appliance assembly line. Connector design features like color coding and mechanical keying may not reduce mating force, but they remove uncertainty and allow workers to easily identify their connection points and feel confident in their decisions. 

Mental and physical health are also cyclical. It may sound obvious that a workplace built to reduce injury and to promote comfort will result in happier employees. But happier employees are also more efficient. On the assembly line, efficiency results in fewer mistakes, reducing both injuries caused from repetition and from pressured decision making. 

Designing a product for ergonomic assembly not only benefits the operators on the factory floor, but the business and its customers as well. Having safer, happier employees helps with employee retention, performance and avoiding the costs associated with recruiting and hiring. 

While they may not know it, the end user of an appliance benefits greatly from ergonomic design for assembly. If an operator on a refrigerator assembly line is fatigued, they may not fully seat the connector that runs the ice maker. Two months later, the person who purchased that refrigerator notices that it no longer produces ice and files a warranty claim. A connector with an optimal mating force and audible or tactile feedback could have helped avoid this warranty claim — and the associated burden on both the consumer and the manufacturer.

For Molex, the customer experience doesn’t end with the design engineer. We’re proud to partner with leading home appliance manufacturers to tackle the challenges of creating safer assembly environments, reducing injury, improving cognitive wellbeing and contributing to better business. That’s why we incorporate features like terminal position assurance (TPA), positive-lock housings, polarization, colors and keying to minimize repetition, error and uncertainty. 

By actively listening to the needs of our customers and their assembly operators, we’re personalizing solutions to the specific requirements across the entire product lifecycle — from performance characteristics to assembly safety considerations like mating force. No matter the need, there’s a team of Molex engineers ready to help transform the future and improve lives.

Interested in learning more about how Molex designs for ergonomics? 

Download our whitepaper, Ergonomic Considerations Within Electronic Connector Design.