Discover how canted coil springs are used for EMI shielding and electrical contact applications. Learn their working principles, advantages, materials, and why they outperform traditional EMI shielding solutions.
As electronic systems become smaller, faster, and more complex, EMI-Abschirmung and reliable electrical contact performance have become critical design requirements. Electromagnetic interference (EMI) can degrade signal integrity, reduce system reliability, and cause compliance failures with international EMC standards.
One highly effective yet often overlooked solution is the Schrägzugfeder. Originally developed for high-reliability mechanical applications, canted coil springs are now widely used in EMI shielding and electrical contact applications across aerospace, defense, medical devices, semiconductor equipment, and high-performance electronics.
This article explores how schräge Schraubenfedern enable superior EMI shielding and electrical contact performance, how they work, their advantages over traditional shielding methods, and key design considerations for engineers.
Electromagnetic interference (EMI) refers to unwanted electromagnetic energy that disrupts the normal operation of electronic devices. EMI can be generated internally by electronic components or externally by nearby equipment.
Without effective EMI-Abschirmung, systems may experience:
Effective EMI shielding requires more than just a conductive material—it depends on consistent, low-resistance electrical contact between mating surfaces.
Key requirements include:
This is where canted coil springs offer a distinct advantage.
A Schrägzugfeder is a precision spring formed by coiling wire at a specific angle relative to the spring axis. Unlike conventional compression springs, the coils are intentionally tilted, allowing them to flex, rotate, and distribute load evenly during compression.
This unique geometry enables the canted coil spring to provide:
Unter EMI shielding applications, a canted coil spring acts as a continuous conductive interface between two surfaces, ensuring effective grounding and signal containment.
When installed in a groove and compressed, the spring maintains uniform pressure against mating surfaces, forming a reliable 360-degree electrical connection.
Unlike fingerstock or stamped contacts, canted coil springs automatically compensate for:
This self-adjusting behavior ensures consistent EMI shielding performance throughout the product’s life cycle.
Canted coil springs excel as elektrische Kontakte due to their mechanical and conductive characteristics.
These features make canted coil springs ideal for connectors, grounding paths, battery contacts, and shield terminations.
| Merkmal | Canted Coil Feder | Fingerstock | Conductive Elastomer |
|---|---|---|---|
| EMI Shielding Effectiveness | Excellent | Good | Good |
| Contact Force Consistency | Excellent | Poor | Fair |
| Ermüdung Leben | Very Long | Limited | Moderate |
| Elektrische Leitfähigkeit | Excellent | Excellent | Moderate |
| Compression Set | Minimal | N/A | High |
| Installation in Grooves | Yes | Limited | Yes |
From both an EMI-Abschirmung and electrical contact standpoint, canted coil springs offer superior long-term performance.
Material selection plays a critical role in EMI shielding effectiveness and durability.
| Material | Key Benefits |
|---|---|
| Beryllium-Kupfer | Excellent conductivity, fatigue resistance |
| Rostfreier Stahl | Korrosionsbeständigkeit |
| Elgiloy®. | High strength and long fatigue life |
| Inconel®. | High-temperature performance |
| Phosphor-Bronze | Good conductivity and formability |
Plating options such as tin, silver, or gold can further enhance EMI shielding and corrosion resistance.
Proper groove design is essential for optimal EMI shielding performance.
| Groove Type | Typical Application |
|---|---|
| Rectangular Groove | Standard EMI shielding |
| Dovetail Groove | High-vibration environments |
| Tapered Groove | Easy installation |
| V-Groove | Compact designs |
Correct groove design ensures consistent compression and reliable electrical contact.
Canted coil springs are used in a wide range of EMI shielding and electrical contact applications, including:
Their ability to maintain stable EMI shielding under vibration and temperature extremes makes them ideal for mission-critical systems.
Canted coil springs maintain EMI shielding effectiveness under:
Unlike conductive elastomers, they do not suffer from compression set or material aging.
Most EMI shielding canted coil springs are custom-designed to meet specific application requirements.
Customization ensures optimal EMI shielding and electrical contact performance.
From a design perspective, canted coil springs help engineers:
They often replace multiple components with a single multifunctional solution.
Canted coil springs support compliance with common EMI/EMC standards such as:
Their predictable performance helps ensure consistent shielding effectiveness during certification testing.
Canted coil springs for EMI shielding and electrical contact applications provide a unique combination of mechanical reliability and electrical performance. Their angled-coil design delivers consistent contact force, excellent EMI shielding effectiveness, and long-term durability in demanding environments.
Compared to traditional EMI shielding solutions, canted coil springs offer superior fatigue life, stable electrical contact, and adaptability to complex mechanical tolerances. For engineers designing high-reliability electronic systems, they represent one of the most effective EMI shielding solutions available today.