Bonding Sensors in the Car

September 22, 2016 // By Daniel Lenssen, DELO Industrial Adhesives
These days, dozens of sensors are used in one vehicle, a trend that continues to grow. Many of them have components that are fixed with adhesives and protected with encapsulants. Requirements are particularly demanding in vehicles and the adhesives need to work reliably for long periods of time in challenging surroundings like the engine compartment. Here are some tips on which type of adhesive is most appropriate for which sensor.

Sensors can generally be found anywhere in the car where information can be measured and then relayed. They often have the task of capturing physical variables such as temperature, pressure, position, or speed. Because these signals are then passed on to control units and evaluation electronics, the sensors must be reliably sealed against any aggressive media. Sensors that are used in harsh environmental conditions, e.g. for monitoring the oil level or pressure, must be composed of dependable materials. Encapsulants and adhesives that are particularly tolerant of high temperatures and have good chemical characteristics are especially suitable for these types of applications.

This article focuses on parking distance, tire pressure, speed, position, mass air-flow, and TMAP sensors.

Safe Parking Made Easy

When it comes to parking distance sensors, it is essential that the driver be able to depend on the accuracy of the data. This is because sensors help the driver safely maneuver their car into small parking spaces. If the sensor fails, it can be very expensive for the driver. So it is particularly important that the adhesive used has good acoustic characteristics such as the right oscillation behavior in addition to mechanical functionality, so that the ultrasonic signal is transmitted unadulterated and in high-quality. Due to their position in the bumper, the temperature requirements are moderate. The adhesives should be usable in a temperature range from -40 to +85 °C. In addition, they have to pass special automotive tests, such as temperature and salt spray tests.

Light-curing epoxy resins meet exactly these requirements and allow for in-line processes and short cycle times in series production, while enabling reliable curing of shadowed areas by preactivation. In view of the continuously increasing demand, ultrasonic sensor manufacturers can efficiently produce high volumes.

Installed in many new cars: Parking distance sensors

Under Pressure

Sensors are also used as alarm triggers as soon as the pressure drops. They are therefore very important with respect

Design category: