What Are Flat Springs and How Do They Work?

Flat spring by Monroe Engineering

When most people think of springs, they envision pieces of coiled metal. There are extension springs and compression springs, both of which consist of a single piece of coiled metal. Extension springs simply create a pulling force from their respective ends, whereas compression springs create a pushing force from their respective ends. Flat springs, however, feature a different design. Rather than a coiled piece of metal, flat springs consist of a piece of flat and uncoiled metal.

Overview of Flat Springs

Flat springs are energy-storing mechanical devices that are characterized by a flat design. The adjacent photo depicts a set of flat springs. The three springs depicted in the photo are flat springs. They don’t feature a coiled design like that of extension or compression springs. Flat springs feature a flat design, which distinguishes them from their extension and compression counterparts.

How Flat Springs Work

You can find flat springs in different sizes and other specifications. Nonetheless, most of them work in the same way. They are made of flat metal stock, such as stainless steel. The flat metal stock is stamped to achieve the desired design.

While they may look flat, most flat springs still have a slight curvature to them. They are essentially cupped. With this curvature, they can store mechanical energy. When you place a flat spring under a weight-bearing object, it will compress due to its cupped design. This compression will allow the flat spring to both store, as well as release, the object’s energy. The flat spring will essentially flatten, but because it features a cupped design, it will exert force against the object with which it’s used.

Things to Consider When Choosing Flat Springs

If you’re planning to buy flat springs, there are several things you should consider when choosing them. You should consider the material, for example. Nearly all flat springs are made of metal, with flat metal stock being the most common. With that said, flat springs are available in different types of metal. Some of them are made of 301 stainless steel, whereas others are made of high-carbon steel. Stainless steel flat springs offer better protection against corrosion, but high-carbon flat springs are stronger and able to support heavier loads.

You should consider the size when choosing flat springs. Most flat springs are relatively small, but they are still available in different sizes. Consider the height, width and depth when choosing flat springs to ensure that they will work with your application.