What is a flat coil spring?
A flat coil spring, also known as bell spring called, is a spring that consists of coiled flat strip steel. By unwinding or unwinding, the spring provides a controlled torsional force, making it suitable for applications with rotation, backflow or constant force storage within limited space.
There are two main variants of the bell spring. The first is a version where the windings do not touch each other during use. This spring unwinds almost frictionlessly, so there is no loss of energy. This variant is ideal for applications where efficiency and constant power are important, although the maximum time to be generated is relatively lower.
The second variant is the so-called motor spring, where the windings are close to each other. This type is used for applications where higher strength is required in a short period of time, such as wind-up toys or return mechanisms. The power and number of revolutions depend on the number of turns and the available installation space. By lightly greasing the windings, internal friction can be reduced, which is beneficial for longevity and performance.
At De Spiraal, we design and produce both types fully customized, tailored to the application, desired force flow and structural requirements.
Applications of flat coil springs
- Medical: In the medical industry, flat spiral springs are primarily used in MRI and X-ray equipment. They function as part of positioning systems or dosing mechanisms, where precise, silent, and controlled movements are essential. Thanks to the use of non-magnetic materials such as stainless steel, they are also suitable for applications in sensitive, radiation-free environments.
- Mechanical engineering: In general mechanical engineering, flat spiral springs are used in a wide range of mechanisms involving rotation, locking, or return motion. They function as a torsion source in rotary couplings, as energy storage in control systems, or as a component in automatic return mechanisms. Due to their compact design and stable force characteristics, they are widely used in conveyor systems, pick-and-place units, and locking mechanisms.
- Defence & Aerospace: In the defence and aerospace sectors, flat spiral springs are applied in systems where absolute reliability and resistance to extreme conditions are required. Typical applications include weapon systems, locking mechanisms, and aircraft interiors, where the spring provides controlled force build-up or return motion within limited space. Thanks to their high fatigue resistance and corrosion-resistant materials, they continue to perform under high loads, temperature fluctuations, and vibrations.
Why choose De Spiraal as a flat coil spring specialist?
Flat spiral springs from De Spiraal stand for precision, strength, and reliability. We deliver custom solutions that perfectly match your application, from fine mechanical systems to industrial drive mechanisms. Using advanced techniques such as CNC cutting and heat treatment, we produce springs with consistent quality and high dimensional stability. Our experts actively support you in design, material selection, and execution, ensuring that every clock spring performs exactly as intended. Whether you need a single component or a complete production series, we deliver quickly, accurately, and with personal technical support. With De Spiraal, you choose a technical spring partner that represents craftsmanship and certainty.
Benefits of our flat coil springs
- Compact and powerful: Our springs deliver high torsional values in an extremely compact form factor, making them ideal for applications where space is limited without compromising strength or durability.
- Fully custom-made: Each design is tailored to your requirements in terms of winding direction, force characteristics, number of coils, and mounting method, ensuring seamless integration into your mechanism, functionally and structurally.
- Wear- and fatigue-resistant: Designed for applications involving intensive cycles, vibrations, or shock loads. Carefully selected materials and controlled heat treatment ensure long-term performance, even after millions of movements.
- Corrosion- and temperature-resistant: For applications in humid or aggressive environments, we supply stainless steel variants or springs with surface treatment, providing resistance to corrosion, cleaning agents, and temperature fluctuations.
- Reproducible spring characteristics: CNC production and digital quality control ensure that every spring is identical to the previous one, guaranteeing consistent performance in series production where deviations are unacceptable.
- Fast lead times, even for custom solutions: With an in-house tool shop and extensive material stock, we can respond quickly, even for prototypes, small batches, or urgent deliveries, without compromising on quality.
Order custom flat coil springs from De Spiraal
Are you looking for a reliable bell spring for your application? At De Spiraal, we provide technical suspension solutions that perform with precision, from the first prototype to serial delivery. Our specialists are happy to advise you about design, material and application. Whether it concerns precision precision or heavy industrial applications: we make sure it fits.
Looking for a flat coil spring that suits your application?
Contact us at +31 (0) 74 — 291 45 08
