Automotive SBR Systems: How Micro Switches Ensure Passenger Safety

Introduction

In the realm of modern automotive safety, the Safety Belt Reminder (SBR) system plays a critical role. SBR, which stands for Safety Belt Reminder, is a device designed to alert occupants to fasten their seatbelts. As a leading micro switch manufacturer, Guangzhou Unionwell understands the precision required for these life-saving components. This article explores how SBR systems work and why the choice of micro switch is vital for vehicle safety.

What is an Automotive SBR System?

The SBR system is typically installed inside the vehicle seat, positioned between the seat foam and the leather cover, or between the foam and the seat frame. Its primary function is to detect occupant presence. If a passenger is seated but has not fastened their safety belt, the system triggers an audible chime or a warning light to remind them.

Beyond basic safety, these occupant sensing systems are widely used in other applications, such as:

• Airbag Sensing Devices: Determining if an airbag should deploy.

• Taxi Automatic Billing: Detecting when a passenger enters the vehicle.

• Driver Departure: Sensing when the driver leaves the seat.

How Does It Work: Micro Switch vs. Membrane Sensors

There are generally two design solutions available in the market for SBR systems:

1. Membrane Resistor Based: Usually installed directly on the foam under the leather seat.

2. Micro Switch Based: Typically installed on the seat spring frame.

At Unionwell, we specialize in the high-precision mechanical approach. The working principle of a seat sensing system based on a micro switch is reliable and direct:

• When a passenger sits, the pressure creates a force.

• A keycap or press block transmits this force to the button.

• This triggers the micro switch inside the assembly.

• The circuit connects or disconnects to transmit the signal to the car's control unit.

  
  

Product Spotlight: Unionwell G3 & G20 Series

For automotive engineers looking for a robust solution, Unionwell introduces the G3 and G20 Series Automotive Seat Switches.

Key Features of the G3/G20 Module:

• Ingenious Composition: The unit consists of four main parts: a press block, a base, a spring, and the core micro switch.

• Simplified Design: The structure is streamlined, making the press block operation simpler and more effective compared to complex alternatives.

• Compact & Durable: Our switches are designed to be lightweight with a compact structure, offering high repeatability and durability essential for the automotive environment.

Why Choose Unionwell for Automotive Switches?

Guangzhou Unionwell (and our production base Huizhou Greetech) is a professional manufacturer serving top-tier customers in the automotive industry. Here is why global partners trust us:

1. Global Certifications: Our products are backed by comprehensive global safety certifications, including UL, cUL, ENEC, and CQC. Most importantly for the auto sector, our production base is IATF16949 certified.

2. High Reliability: We offer products with high life expectancy and reliability, comparable to first-tier international brands, but at a more competitive price point.

3. Customization: We provide a variety of terminal configurations to meet different wiring harness requirements.

   
   

Conclusion

Whether for seat belt alarms, airbag sensors, or industrial control, the quality of the micro switch determines the reliability of the system. Unionwell’s G3 and G20 series offer the precision and durability modern vehicles demand.

Looking for a reliable SBR switch solution?

Visit https://www.unionwellgz.com/ to explore our full range of automotive switches or contact our engineering team for 3D drawings and samples.