Today sensors are common in household appliances. Sensors are utilized in refrigerators, washers, dryers, and other appliances, offering better control over a variety of functions. They enable energy efficiency, and ensure reliability and safe operation of the appliance. Additionally, household appliances are becoming smarter—therefore sensors are playing an even greater role in how consumers interact with these appliances.

Household appliance manufacturers want sensors in their products to work properly and be reliable. No one wants the temperature sensor in a refrigerator to stop working—that could result in a refrigerator that is either too warm or cold, and either spoiled or frozen food. Or, what if a temperature or water level sensor fails in a clothes dryer? It may not heat or it could over heat, and be a fire hazard. These are just two examples of what can happen when a sensor malfunctions or stops working.

There are many useful applications of sensors in refrigerators, including temperature control, humidity level, door position, water/ice dispenser lever, drawer and compartment cover position, ice bucket fill level and drain pan level. In washing machines sensors are used for lid/door position, water level, dial position, drum speed, and detergent level. Sensors in clothes dryers are used for door closure, lint filter, dryer rotary selector and drum speed. Both washing machines and dryers use temperature sensors to control the temperature of inflow and outflow water and air.

Sensor material requirements

The key to having reliable sensors is to use material solutions that meet specific requirements—this will ensure reliability and safety. The key materials requirements include:

Tensile strength/shear modulus:

• Reduced notched sensitivity–cracking.
• For replaceable parts, fatigue performance is very important.      
• This combination of properties will help to meet high torque requirements during installation.

Flow :

• Most sensors encapsulate the sensor element and/or its leads.
• Encapsulation should be without damage to the sensor/leads.
• Material should generate a seal on these elements.

Other sensors requirements may include high temperature relaxation/creep resistance (clamp force retention); usage temperature range from -40°C up to 70°C, peak temperature of 90°C; and part integration feasibility.

Envalior’s material solutions meet these key requirements as per technical and commercial requirement. For example, Arnite^® can be used for pressure sensor in air conditioners or air flow sensor in refrigerators, and Akulon^® has been used for sensor bobbins in washing machines. There are other potential applications (in the automotive industry) where these materials can be used for moving parts like wheel speed sensors, water level/ temperature sensors, position sensors and air intake sensors.

To learn more about Envalior's material portfolio or to request test samples, contact us or visit plasticsfinder.envalior.com for additional information, including technical data sheets.